PE Pipe Design and Engineering Guide (PolyPipe)

Transcription

PolyPipe
®
Design and Engineering Guide
for Polyethylene Piping
TABLE OF CONTENTS
CONTENTS
SECTION
Pipe Data and Pressure Ratings
Fluid Flow
Earthloading
Temperature Effects
Chemical Resistance
Installation
Marine Application
Slurry Application
Overhead Pipeline Application
Natural Gas Flow
Handling and Storage
Conversion Factors
Material Safety Data Sheet (MSDS)
SUBJECT MATTER
Anchor Weight Design
Bending Radius
Cell Classification
Coiled Pipe
Critical Buckling Factors (Non-Supported)
Design/Construction of Ballast Weights
External Pressure Ratings
Gravity Flow
Hydrostatic Pressure Testing
Internal Pressure Ratings
Maximum Pulling Force, MPF
Maximum Pulling Length, MPL
Physical Properties
Pipe Supports/Spacing
Pipe Weights & Dimensions – PE3408
Pipe Weights & Dimensions – PE2406
Pressure Loss/Gain –Elevation
Pressure Loss/Gain –Fittings
Pressure Loss/Gain –Frictional
Pressure Surge/Water Hammer
Pressure Testing
Sag
Thermal Conductivity
Thermal Expansion/Contraction
Thrust Blocking
Trench Configuration/Terminology
UV Resistance
Vacuum Systems
Velocities – Liquid
Velocities – Slurry
A
B
C
D
E
F
G
H
J
L
M
N
P
SECTION
PAGE
G
F
A
L
A
G
A
B
F
A
F
F
A
J
A
L
B
B
B
B
F
J
D
D
F
F
M
A
B
H
3
2
2
2
13
4-6
16 - 17
5
6-8
15 - 16
3
3
1
1-2
3 - 11
4-5
3
4
2
7
6
1
1
1-3
2
5
3
18
1
3
i
PolyPipe 12/05
TABLE OF CONTENTS (cont.)
TABLES
A-1
A-2
A-3
A-4
A-5
A-6
A-7
A-8
B-1
B-2
B-3
B-4
C-1
C-2
C-3
C-4
D-1
F-1
F-2
F-3
G-1
G-2
H-1
L-1
L-2
L-3
M-1
Nominal Physical Properties
Pipe Weights and Dimensions, PE3408 (IPS)
Pipe Weights and Dimensions, PE3408 (Metric)
Pipe Weights and Dimensions, PE3408 (DIPS)
Environmental Service Factors
Internal Pressure Ratings for PolyPipe®
External Pressure Ratings for PolyPipe®, Non-Supported Application
Time Correction Factors
Recommended Liquid Velocities
Hazen-Williams Coefficients for Various Pipes
Pressure Drop in Fittings
Fullness Factors, Gravity Flow
Design Limits for Ring Deflection
Area Reduction Due to Ring Deflection
Classification of Backfill Material
Typical Soil Modulus Values
Thermal Conductivity of Materials
Minimum Bending Radius
Tensile Yield Strengths
Hydrostatic Test Phase Make-Up Amount
Anchor Constant Values
Suggested Concrete Weight Dimensions
Suggested Fluid Velocities, Slurry
Typical Maximum Flow Rates for Natural Gas Distribution Systems
Pipe Weights and Dimensions, PE2406 (IPS)
Pipe Weights and Dimensions, PE2406 (CTS)
Loose Pipe Storage, Suggested Stacking Heights
FIGURES
A-1
A-2
C-2
C-3
C-4
C-5
C-6
F-1
F-2
F-3
F-4
G-1
G-2
J-1
M-1
Operational Life Factors
Temperature Corrections Factors
Trench Coefficient Values
Wall Buckling Diagram
Resultant Surface Load Diagram
H20 Highway Loading
Cooper E-80 Loading
Ditch Configurations
Proper Backfill
Trench Configuration
Proper Haunching
Schematics of Concrete Ballast Designs
Typical Detail of Concrete Ballast
Support Spacing for Intermittently Supported Pipelines
Forklift Load Capacity
SECTION
PAGE
A
A
A
A
A
A
A
A
B
B
B
B
C
C
C
C
D
F
F
F
G
G
H
L
L
L
M
1
3-8
8
9 - 11
13
15 - 16
16 - 17
18
1
3
4
5
1
2
3
4
1
2
3
8
3
5
3
1
4
5
3
SECTION
PAGE
A
A
C
C
C
C
C
F
F
F
F
G
G
J
M
14
14
3
5
6
6
7
1
4
5
5
5
6
1
2
ii
PolyPipe 12/05
INTRODUCTION
PolyPipe® PE3408 high density, high molecular weight, polyethylene pipe and fittings are made from a
polyethylene resin expressly developed for demanding pressure piping applications. The use of PolyPipe®
PE3408 pipe and fittings, as prescribed in this Guide, can help assure a sound, functional, economical system.
PolyPipe® polyethylene piping systems allow the design engineer the opportunity to select premium polyethylene
piping materials to perform as well as or better than alternate materials due to any one of the inherent
characteristics of polyethylene. These are as follows:
Long-Term Strength
Flexibility
Corrosion Resistance
Chemical Resistance
Toughness
Weatherabilty
Installed Cost
Ease of Installation
Failure Mechanism
Low Friction Loss
Non-toxic
Low Thermal Conductivity
No Galvanic Action
Abrasion Resistance
While this Guide details the benefits of industrial and mining piping materials, the same nominal values can be
applied to oil patch pipe, gas distribution pipe, water pipe and municipal wastewater pipe.
iii
PolyPipe 12/05
FOREWORD
The Design and Engineering Guide for Polyethylene Piping, hereinafter referred to as "Guide," defines engineering
requirements deemed necessary for the safe design and construction of PolyPipe® polyethylene piping systems.
While safety is a basic consideration in this Guide, the user should be aware of other safety measures to consider
in the safe installation or operation of the piping system. This Guide contains prohibitions in some areas where
practice can be unintentionally easily extended into an unsafe condition, and in other areas, "flags" of caution are
offered.
The Guide is intended to provide basic principles in areas of concern when designing a piping system. However, it
does not replace the need for competent engineering evaluation and judgment.
The Guide contains basic reference data and formulas necessary for design of a PolyPipe® piping system. These
formulas are recognized industry standard adaptations and, in most cases, modified for ease of application to
PolyPipe® systems. It is intended to state these in terms of basic design principles to the maximum extent
possible, supplemented where necessary, with examples to obtain uniform and accurate interpretation.
PolyPipe® also has available a CD Rom to aide in calculations of formulas presented in the Sections of this Guide.
To request a CD Rom, please visit our website at www.polypipeinc.com.
If additional technical assistance is needed, please contact the PolyPipe® Technical Services Department at (800)
433-5632.
A comprehensive, industry consensus design guide for the proper use of polyethylene pipe is available from the
Plastics Pipe Institute (PPI). The design guide is available, free of charge, via download from the PPI website at
www.plasticpipe.org.
iv
PolyPipe 12/05
PIPE DATA
Table A-1
NOMINAL PHYSICAL PROPERTIES
POLYPIPE® PE3408 AND PE2406 PIPE MATERIAL
PROPERTY
ASTM
TEST METHOD
Nominal Value*
PE3408
PE2406
Cell Classification
D3350
345464C
234363E
Density, Natural
D1505
0.946 gm/cc
0.940 gm/cc
Density, Black (PE3408) or Yellow (PE2406)
D1505
0.955 gm/cc
0.943 gm/cc
Melt Index (190oC/2.16 kg)
D1238
0.07 gm/10 min
0.2 gm/10 min
Flow Rate (190oC/21.6 kg)
D1238
8.5 gm/10 min
20 gm/10 min
Flexural Modulus
D790
136,000 psi
100,000 psi
Elastic Modulus: short-term
D638
125,000 psi
100,000 psi
Elastic Modulus: long-term
D638
30,000 psi
25,000 psi
Tensile Strength @ Yield
D638
3,500 psi
2,800 psi
ESCR
D1693
>10,000 hrs. failure
>10,000 hrs. failure
F1473
>100 hrs.
>1,000 hrs.
HDB @ 73.4oF
D2837
1,600 psi
1,250 psi
HDB @ 140oF
D2837
800 psi
1,000 psi
UV Stabilizer (Carbon)
D1603
2.5%
2.5%
Brittleness Temperature
D746
<-180oF
<-180oF
Melting Point
D789
261oF
261oF
Vicat Softening Temperature
D1525
255oF
248oF
Hardness
D2240
64
64 Shore D
Izod Impact Strength (Notched)
D256
7 ft-lbf/in
10 ft-lbf/in
Thermal Expansion Coefficient
D696
1.0 x 10-4 in/in/oF
1.0 x 10-4 in/in/oF
Poisson’s Ratio
--
0.42
0.42
Manning Roughness
--
0.01
0.01
Volume Resistivity
D991
2.6 x 1016 Ω-cm
2.6 x 1016 Ω-cm
Average Molecular Weight
GPC
330,000
330,000
Slow Crack Growth, PENT
*Note: Nominal Values are not intended as specified limits.
A-1
PolyPipe 12/05
CELL CLASSIFICATION
ASTM material standards insure that resins produced for piping applications are capable of providing a consistent
level of performance over the intended design life. The most prevalent ASTM material specification is ASTM
D3350. Multiple physical properties are defined within this specification by the use of a cell-type format for the
identification, close characterization and specification of material properties.
The cell-type format consists of six (6) numbers and a letter. PolyPipe® high density, extra high molecular weight,
PE3408 polyethylene pipe material has a cell classification of 345464C. The letter “C” denotes the color and UV
stabilization and is in accordance with the following code: A – Natural, B – Colored, C – Black with 2% minimum
carbon black, D – Natural with UV stabilizer, and E – Colored with UV stabilizer.
Property
Method
0
1
2
3
4
5
6
Density, g/cm3
D1505
Unspecified
0.925 or
lower
>0.925 –
0.940
> 0.940 –
0.955
>0.955
-----
-----
Melt Index
D1238
Unspecified
>1.0
1.0 – 0.4
<0.4 – 0.15
< 0.15
A
Flexural Modulus,
psi
D790
Unspecified
<20,000
20,000 <40,000
40,000 –
80,000
80,000 –
110,000
110,000 <160,000
>160,000
Tensile strength at
Yield, psi
D638
Unspecified
<2200
2200 <2600
2600 <3000
3000 <3500
3500 <4000
>4000
D1693
Unspecified
a. Test Condition
A
B
C
C
-----
-----
b. Test Duration, h
48
24
192
600
c. Failure, max, %
50
50
20
20
0.1
1
3
10
30
100
800
1000
1250
1600
Slow Crack Growth
Resistance
I. ESCR
II. PENT (hours)
F1473
Unspecified
Molded plaque,
80oC, 2.4 MPa
Hydrostatic Design
Basis, psi, (23oC)
D2837
NPRB
A
Refer to 10.1.4.1 of ASTM D3350.
NPR = Not Pressure Rated.
B
Being a polyethylene (PE) material, the abbreviation PE is used preceding the cell number P-E-3-4-5-4-6-4-C. The
Plastics Pipe Institute (PPI), a division of the Society of the Plastics Industry, Inc., has rated PolyPipe® material as
PE3408.
A-2
PolyPipe 12/05
Table A-2
PIPE WEIGHTS AND DIMENSIONS (IPS)
PE3408 (BLACK)
OD
Nominal
in.
1/2
3/4
1
1 1/4
1 1/2
2
Nominal ID
Actual
in.
mm.
0.840
1.050
1.315
1.660
1.900
2.375
21.34
26.67
33.40
42.16
48.26
60.33
Minimum Wall
SDR
Weight
in.
mm.
in.
mm.
lb. per
foot
kg. per
meter
7
7.3
9
9.3
11
11.5
0.59
0.60
0.64
0.65
0.68
0.69
14.87
15.14
16.31
16.47
17.22
17.40
0.120
0.115
0.093
0.090
0.076
0.073
3.05
2.92
2.37
2.29
1.94
1.86
0.118
0.114
0.095
0.093
0.080
0.077
0.175
0.170
0.142
0.138
0.119
0.114
7
7.3
9
9.3
11
11.5
0.73
0.75
0.80
0.81
0.85
0.86
18.59
18.92
20.39
20.59
21.53
21.75
0.150
0.144
0.117
0.113
0.095
0.091
3.81
3.65
2.96
2.87
2.42
2.32
0.184
0.178
0.149
0.145
0.125
0.120
0.274
0.265
0.222
0.216
0.186
0.179
7
7.3
9
9.3
11
11.5
0.92
0.93
1.01
1.02
1.06
1.07
23.29
23.70
25.53
25.79
26.96
27.24
0.188
0.180
0.146
0.141
0.120
0.114
4.77
4.58
3.71
3.59
3.04
2.90
0.289
0.279
0.234
0.227
0.196
0.188
0.430
0.415
0.348
0.338
0.291
0.280
7
7.3
9
9.3
11
11.5
13.5
1.16
1.18
1.27
1.28
1.34
1.35
1.40
29.39
29.92
32.23
32.55
34.04
34.39
35.54
0.237
0.227
0.184
0.178
0.151
0.144
0.123
6.02
5.78
4.68
4.53
3.83
3.67
3.12
0.461
0.445
0.372
0.362
0.312
0.300
0.259
0.685
0.662
0.554
0.539
0.464
0.446
0.386
7
7.3
9
9.3
11
11.5
13.5
15.5
1.32
1.35
1.45
1.47
1.53
1.55
1.60
1.64
33.64
34.24
36.89
37.26
38.96
39.36
40.68
41.66
0.271
0.260
0.211
0.204
0.173
0.165
0.141
0.123
6.89
6.61
5.36
5.19
4.39
4.20
3.57
3.11
0.603
0.583
0.488
0.474
0.409
0.393
0.340
0.299
0.898
0.867
0.726
0.706
0.608
0.585
0.506
0.445
7
7.3
9
9.3
11
11.5
13.5
15.5
17
1.66
1.69
1.82
1.83
1.92
1.94
2.00
2.05
2.08
42.06
42.81
46.12
46.57
48.70
49.20
50.85
52.07
52.80
0.339
0.325
0.264
0.255
0.216
0.207
0.176
0.153
0.140
8.62
8.26
6.70
6.49
5.48
5.25
4.47
3.89
3.55
0.943
0.911
0.762
0.741
0.639
0.614
0.531
0.467
0.429
1.403
1.355
1.134
1.103
0.951
0.914
0.790
0.696
0.638
See ASTM D3035, F714 and AWWA C-901/906 for OD and wall thickness tolerances.
Weights are calculated in accordance with PPI TR-7.
A-3
PolyPipe 12/05
Table A-2 (cont'd)
PE3408 (BLACK)
OD
Nominal
in.
3
4
5
6
Nominal ID
Actual
in.
mm.
3.500
4.500
5.563
6.625
88.90
114.30
141.30
168.28
Minimum Wall
SDR
Weight
in.
mm.
in.
mm.
lb. per
foot
kg. per
meter
7
7.3
9
9.3
11
11.5
13.5
15.5
17
21
26
2.44
2.48
2.68
2.70
2.83
2.85
2.95
3.02
3.06
3.15
3.21
61.98
63.08
67.96
68.63
71.77
72.51
74.94
76.74
77.81
79.93
81.65
0.500
0.479
0.389
0.376
0.318
0.304
0.259
0.226
0.206
0.167
0.135
12.70
12.18
9.88
9.56
8.08
7.73
6.59
5.74
5.23
4.23
3.42
2.047
1.978
1.656
1.609
1.387
1.333
1.153
1.015
0.932
0.764
0.623
3.047
2.943
2.464
2.395
2.065
1.984
1.716
1.511
1.386
1.136
0.927
7
7.3
9
9.3
11
11.5
13.5
15.5
17
21
26
32.5
3.14
3.19
3.44
3.47
3.63
3.67
3.79
3.88
3.94
4.05
4.13
4.21
79.68
81.11
87.38
88.24
92.27
93.23
96.35
98.67
100.05
102.76
104.98
106.84
0.643
0.616
0.500
0.484
0.409
0.391
0.333
0.290
0.265
0.214
0.173
0.138
16.33
15.66
12.70
12.29
10.39
9.94
8.47
7.37
6.72
5.44
4.40
3.52
3.384
3.269
2.737
2.660
2.294
2.204
1.906
1.678
1.540
1.262
1.030
0.831
5.037
4.865
4.073
3.958
3.413
3.280
2.836
2.497
2.292
1.879
1.533
1.237
7
7.3
9
9.3
11
11.5
13.5
15.5
17
21
26
32.5
3.88
3.95
4.25
4.29
4.49
4.54
4.69
4.80
4.87
5.00
5.11
5.20
98.51
100.27
108.02
109.09
114.07
115.25
119.11
121.97
123.68
127.04
129.78
132.08
0.795
0.762
0.618
0.598
0.506
0.484
0.412
0.359
0.327
0.265
0.214
0.171
20.19
19.36
15.70
15.19
12.85
12.29
10.47
9.12
8.31
6.73
5.43
4.35
5.172
4.996
4.182
4.065
3.505
3.368
2.912
2.564
2.353
1.929
1.574
1.270
7.697
7.435
6.224
6.049
5.216
5.012
4.334
3.816
3.502
2.871
2.343
1.890
7
7.3
9
9.3
11
11.5
13.5
15.5
17
21
26
32.5
4.62
4.70
5.06
5.11
5.35
5.40
5.58
5.72
5.80
5.96
6.08
6.19
117.31
119.41
128.64
129.92
135.84
137.25
141.85
145.26
147.29
151.29
154.55
157.30
0.946
0.908
0.736
0.712
0.602
0.576
0.491
0.427
0.390
0.315
0.255
0.204
24.04
23.05
18.70
18.09
15.30
14.63
12.46
10.86
9.90
8.01
6.47
5.18
7.336
7.086
5.932
5.765
4.971
4.777
4.130
3.637
3.338
2.736
2.233
1.801
10.917
10.545
8.827
8.579
7.398
7.109
6.147
5.413
4.967
4.072
3.322
2.680
A-4
PolyPipe 12/05
Table A-2 (cont'd)
PE3408 (BLACK)
OD
Nominal
in.
8
10
12
14
Nominal ID
Actual
in.
mm.
8.625
10.750
12.750
14.000
219.08
273.05
323.85
355.60
Weight
Minimum Wall
SDR
in.
mm.
in.
mm.
lb. per
foot
kg. per
meter
7
7.3
9
9.3
11
11.5
13.5
15.5
17
21
26
6.01
6.12
6.59
6.66
6.96
7.04
7.27
7.45
7.55
7.75
7.92
152.73
155.45
167.47
169.14
176.85
178.69
184.67
189.11
191.76
196.96
201.21
1.232
1.182
0.958
0.927
0.784
0.750
0.639
0.556
0.507
0.411
0.332
31.30
30.01
24.34
23.56
19.92
19.05
16.23
14.13
12.89
10.43
8.43
12.433
12.010
10.054
9.771
8.425
8.096
7.001
6.164
5.657
4.637
3.784
18.503
17.872
14.962
14.541
12.538
12.049
10.418
9.174
8.418
6.901
5.631
7
7.3
9
9.3
11
11.5
13.5
15.5
17
21
26
32.5
7.49
7.63
8.22
8.30
8.68
8.77
9.06
9.28
9.41
9.66
9.87
10.05
190.35
193.75
208.73
210.81
220.43
222.71
230.17
235.70
239.00
245.48
250.79
255.24
1.536
1.473
1.194
1.156
0.977
0.935
0.796
0.694
0.632
0.512
0.413
0.331
39.01
37.40
30.34
29.36
24.82
23.74
20.23
17.62
16.06
13.00
10.50
8.40
19.314
18.656
15.618
15.179
13.089
12.578
10.875
9.576
8.788
7.204
5.878
4.742
28.743
27.764
23.242
22.589
19.478
18.717
16.184
14.251
13.078
10.721
8.748
7.058
7
7.3
9
9.3
11
11.5
13.5
15.5
17
21
26
32.5
8.89
9.05
9.75
9.84
10.29
10.40
10.75
11.01
11.16
11.46
11.71
11.92
225.77
229.80
247.57
250.03
261.44
264.15
272.99
279.56
283.46
291.16
297.44
302.73
1.821
1.747
1.417
1.371
1.159
1.109
0.944
0.823
0.750
0.607
0.490
0.392
46.26
44.36
35.98
34.82
29.44
28.16
23.99
20.89
19.05
15.42
12.46
9.96
27.170
26.244
21.970
21.353
18.412
17.693
15.298
13.471
12.362
10.134
8.269
6.671
40.433
39.056
32.695
31.777
27.400
26.330
22.767
20.047
18.397
15.081
12.305
9.928
7
7.3
9
9.3
11
11.5
13.5
15.5
17
21
26
32.5
9.76
9.93
10.70
10.81
11.30
11.42
11.80
12.09
12.25
12.59
12.86
13.09
247.90
252.33
271.84
274.54
287.07
290.05
299.76
306.96
311.25
319.70
326.60
332.40
2.000
1.918
1.556
1.505
1.273
1.217
1.037
0.903
0.824
0.667
0.538
0.431
50.80
48.71
39.51
38.24
32.33
30.92
26.34
22.94
20.92
16.93
13.68
10.94
32.758
31.642
26.489
25.745
22.199
21.332
18.445
16.242
14.905
12.218
9.970
8.044
48.750
47.089
39.420
38.313
33.036
31.746
27.449
24.170
22.181
18.183
14.836
11.970
A-5
PolyPipe 12/05
Table A-2 (cont'd)
PE3408 (BLACK)
OD
Nominal
in.
16
18
20
22
Nominal ID
Actual
in.
mm.
16.000
18.000
20.000
22.000
406.40
457.20
508.00
558.80
Minimum Wall
SDR
Weight
in.
mm.
in.
mm.
lb. per
foot
kg. per
meter
7
7.3
9
9.3
11
11.5
13.5
15.5
17
21
26
11.15
11.35
12.23
12.35
12.92
13.05
13.49
13.81
14.00
14.38
14.70
283.32
288.38
310.67
313.76
328.08
331.48
342.58
350.81
355.72
365.37
373.26
2.286
2.192
1.778
1.720
1.455
1.391
1.185
1.032
0.941
0.762
0.615
58.06
55.67
45.16
43.70
36.95
35.34
30.10
26.22
23.91
19.35
15.63
42.786
41.329
34.598
33.626
28.994
27.862
24.092
21.214
19.467
15.959
13.022
63.673
61.504
51.487
50.041
43.149
41.464
35.852
31.570
28.970
23.749
19.378
7
7.3
9
9.3
11
11.5
13.5
15.5
17
21
26
32.5
12.55
12.77
13.76
13.90
14.53
14.68
15.17
15.54
15.76
16.18
16.53
16.83
318.73
324.42
349.50
352.98
369.09
372.92
385.40
394.67
400.18
411.04
419.92
427.38
2.571
2.466
2.000
1.935
1.636
1.565
1.333
1.161
1.059
0.857
0.692
0.554
65.31
62.63
50.80
49.16
41.56
39.76
33.87
29.50
26.89
21.77
17.58
14.07
54.151
52.307
43.788
42.558
36.696
35.263
30.491
26.849
24.638
20.198
16.480
13.296
80.586
77.841
65.164
63.333
54.610
52.478
45.376
39.955
36.666
30.058
24.526
19.787
7
7.3
9
9.3
11
11.5
13.5
15.5
17
21
26
32.5
13.94
14.19
15.29
15.44
16.15
16.31
16.86
17.26
17.51
17.98
18.37
18.70
354.15
360.47
388.34
392.20
410.09
414.35
428.23
438.52
444.65
456.72
466.58
474.86
2.857
2.740
2.222
2.151
1.818
1.739
1.481
1.290
1.176
0.952
0.769
0.615
72.57
69.59
56.44
54.62
46.18
44.17
37.63
32.77
29.88
24.19
19.54
15.63
66.853
64.576
54.059
52.541
45.304
43.535
37.643
33.146
30.418
24.936
20.346
16.415
99.489
96.100
80.449
78.189
67.420
64.787
56.019
49.327
45.266
37.108
30.279
24.429
9
9.3
11
11.5
13.5
15.5
17
21
26
32.5
16.82
16.98
17.76
17.94
18.55
18.99
19.26
19.78
20.21
20.56
427.17
431.42
451.10
455.79
471.05
482.37
489.11
502.39
513.24
522.35
2.444
2.366
2.000
1.913
1.630
1.419
1.294
1.048
0.846
0.677
62.09
60.09
50.80
48.59
41.39
36.05
32.87
26.61
21.49
17.19
65.412
63.574
54.818
52.677
45.548
40.107
36.805
30.172
24.619
19.863
97.343
94.609
81.578
78.393
67.783
59.686
54.772
44.901
36.637
29.559
A-6
PolyPipe 12/05
Table A-2 (cont'd)
PE3408 (BLACK)
OD
Nominal
in.
24
28
30
32
36
42
Nominal ID
Actual
in.
mm.
24.000
28.000
30.000
32.000
36.000
42.000
Minimum Wall
Weight
in.
mm.
in.
mm.
lb. per
foot
9
9.3
11
11.5
13.5
15.5
17
21
26
32.5
18.35
18.53
19.37
19.58
20.23
20.72
21.01
21.58
22.04
22.43
466.01
470.64
492.11
497.22
513.87
526.22
533.58
548.06
559.89
569.84
2.667
2.581
2.182
2.087
1.778
1.548
1.412
1.143
0.923
0.738
67.73
65.55
55.42
53.01
45.16
39.33
35.86
29.03
23.45
18.76
77.845
75.658
65.237
62.690
54.206
47.731
43.801
35.907
29.299
23.638
115.847
112.592
97.084
93.294
80.668
71.032
65.184
53.436
43.601
35.177
11
11.5
13.5
15.5
17
21
26
32.5
22.60
22.84
23.60
24.17
24.51
25.17
25.72
26.17
574.13
580.09
599.52
613.93
622.51
639.40
653.21
664.81
2.545
2.435
2.074
1.806
1.647
1.333
1.077
0.862
64.65
61.84
52.68
45.88
41.84
33.87
27.35
21.88
88.795
85.329
73.781
64.967
59.618
48.874
39.879
32.174
132.142
126.983
109.798
96.682
88.722
72.732
59.346
47.880
11
11.5
13.5
15.5
17
21
26
32.5
24.22
24.47
25.29
25.90
26.26
26.97
27.55
28.04
615.14
621.53
642.34
657.78
666.97
685.07
699.87
712.29
2.727
2.609
2.222
1.935
1.765
1.429
1.154
0.923
69.27
66.26
56.44
49.16
44.82
36.29
29.31
23.45
101.934
97.954
84.697
74.580
68.439
56.105
45.779
36.934
151.694
145.771
126.043
110.987
101.849
83.494
68.127
54.965
13.5
15.5
17
21
26
32.5
26.97
27.62
28.01
28.77
29.39
29.91
685.16
701.63
711.44
730.75
746.53
759.78
2.370
2.065
1.882
1.524
1.231
0.985
60.21
52.44
47.81
38.70
31.26
25.01
96.367
84.855
77.869
63.835
52.086
42.023
143.409
126.278
115.882
94.997
77.513
62.538
914.40
15.5
17
21
26
32.5
31.08
31.51
32.37
33.06
33.65
789.33
800.37
822.09
839.84
854.75
2.323
2.118
1.714
1.385
1.108
58.99
53.79
43.54
35.17
28.14
107.395
98.553
80.791
65.922
53.186
159.821
146.663
120.231
98.102
79.149
1066.80
15.5
17
21
26
32.5
36.26
36.76
37.76
38.58
39.26
920.89
933.76
959.10
979.81
997.21
2.710
2.471
2.000
1.615
1.292
68.83
62.75
50.80
41.03
32.82
146.176
134.141
109.966
89.727
72.392
217.534
199.625
163.648
133.528
107.731
609.60
711.20
762.00
812.80
SDR
kg. per
meter
A-7
PolyPipe 12/05
Table A-2 (cont'd)
PE3408 (BLACK)
OD
Nominal
in.
Nominal ID
Actual
in.
mm.
48
48.000
1219.20
54
54.000
1371.60
Minimum Wall
SDR
Weight
in.
mm.
in.
mm.
lb. per
foot
kg. per
meter
17
21
26
32.5
42.01
43.15
44.09
44.87
1067.16
1096.12
1119.79
1139.67
2.824
2.286
1.846
1.477
71.72
58.06
46.89
37.51
175.205
143.629
117.194
94.552
260.734
213.744
174.404
140.709
21
26
32.5
48.55
49.60
50.48
1233.13
1259.76
1282.13
2.571
2.077
1.662
65.31
52.75
42.20
181.781
148.324
119.668
270.520
220.730
178.085
Table A-3
PIPE WEIGHTS AND DIMENSIONS (Metric)
PE3408 (BLACK)
Metric
Size
OD
mm.
in.
50
1.97
63
Nominal ID
Minimum Wall
SDR
Weight
in.
mm.
in.
mm.
lb. per
foot
kg. per
meter
11
1.59
40.39
0.179
4.55
0.440
0.654
2.48
17
2.17
55.14
0.146
3.71
0.468
0.696
90
3.54
11
2.86
72.59
0.322
8.17
1.419
2.112
110
4.33
11
17
3.50
3.79
88.79
96.27
0.394
0.255
10.00
6.47
2.123
1.426
3.160
2.122
160
6.30
11
32.5
5.09
5.89
129.18
149.58
0.573
0.194
14.55
4.92
4.495
1.629
6.690
2.424
200
7.87
11
17.6
32.5
6.35
6.92
7.36
161.37
175.82
186.86
0.715
0.447
0.242
18.17
11.36
6.15
7.015
4.560
2.542
10.439
6.786
3.783
250
9.84
11
17.6
32.5
7.94
8.65
9.20
201.77
219.83
233.63
0.895
0.559
0.303
22.72
14.20
7.69
10.966
7.128
3.974
16.320
10.608
5.913
315
12.40
17.6
32.5
10.91
11.59
277.02
294.41
0.705
0.382
17.90
9.69
11.319
6.310
16.845
9.390
400
15.75
12
12.97
329.37
1.313
33.34
25.983
38.667
500
19.69
26
18.08
459.35
0.757
19.24
19.720
29.347
A-8
PolyPipe 12/05
Table A-4
PIPE WEIGHTS AND DIMENSIONS (DIPS)
PE3408 (BLACK)
OD
Nominal
in.
3
4
6
8
10
Nominal ID
Actual
in.
mm.
3.960
4.800
6.900
9.050
11.100
Minimum Wall
SDR
Weight
in.
mm.
in.
mm.
lb. per
foot
kg. per
meter
100.58
7
9
11
13.5
15.5
17
21
26
32.5
2.76
3.03
3.20
3.34
3.42
3.47
3.56
3.64
3.70
70.12
76.89
81.20
84.79
86.83
88.04
90.43
92.38
94.02
0.566
0.440
0.360
0.293
0.255
0.233
0.189
0.152
0.122
14.37
11.18
9.14
7.45
6.49
5.92
4.79
3.87
3.09
2.621
2.119
1.776
1.476
1.299
1.192
0.978
0.798
0.644
3.900
3.154
2.643
2.196
1.934
1.775
1.455
1.187
0.958
121.92
7
9
11
13.5
15.5
17
21
26
32.5
3.35
3.67
3.87
4.05
4.14
4.20
4.32
4.41
4.49
85.00
93.20
98.42
102.77
105.24
106.72
109.61
111.98
113.97
0.686
0.533
0.436
0.356
0.310
0.282
0.229
0.185
0.148
17.42
13.55
11.08
9.03
7.87
7.17
5.81
4.69
3.75
3.851
3.114
2.609
2.168
1.909
1.752
1.436
1.172
0.946
5.731
4.634
3.883
3.227
2.841
2.607
2.137
1.744
1.407
175.26
7
9
11
13.5
15.5
17
21
26
32.5
4.81
5.27
5.57
5.82
5.96
6.04
6.20
6.34
6.45
122.18
133.98
141.48
147.74
151.29
153.40
157.57
160.97
163.83
0.986
0.767
0.627
0.511
0.445
0.406
0.329
0.265
0.212
25.04
19.47
15.93
12.98
11.31
10.31
8.35
6.74
5.39
7.957
6.434
5.392
4.480
3.945
3.620
2.968
2.422
1.954
11.842
9.575
8.025
6.668
5.871
5.388
4.417
3.604
2.908
229.87
7
9
11
13.5
15.5
17
21
26
32.5
6.31
6.92
7.31
7.63
7.81
7.92
8.14
8.31
8.46
160.25
175.72
185.57
193.77
198.43
201.20
206.66
211.13
214.88
1.293
1.006
0.823
0.670
0.584
0.532
0.431
0.348
0.278
32.84
25.54
20.90
17.03
14.83
13.52
10.95
8.84
7.07
13.689
11.069
9.276
7.708
6.787
6.228
5.106
4.166
3.361
20.371
16.472
13.805
11.470
10.100
9.269
7.598
6.200
5.002
281.94
7
9
11
13.5
15.5
17
21
26
32.5
7.74
8.49
8.96
9.36
9.58
9.72
9.98
10.19
10.38
196.55
215.53
227.60
237.66
243.38
246.78
253.48
258.95
263.55
1.586
1.233
1.009
0.822
0.716
0.653
0.529
0.427
0.342
40.28
31.33
25.63
20.88
18.19
16.58
13.43
10.84
8.68
20.593
16.652
13.955
11.595
10.210
9.369
7.681
6.267
5.056
30.645
24.780
20.767
17.255
15.194
13.943
11.430
9.327
7.525
A-9
PolyPipe 12/05
Table A-4 (cont'd)
PE3408 (BLACK)
OD
Nominal
in.
12
14
16
18
20
Nominal ID
Actual
in.
mm.
13.200
15.300
17.400
19.500
21.600
Minimum Wall
SDR
Weight
in.
mm.
in.
mm.
lb. per
foot
kg. per
meter
335.28
7
9
11
13.5
15.5
17
21
26
32.5
9.20
10.09
10.66
11.13
11.39
11.55
11.87
12.12
12.34
233.74
256.30
270.66
282.63
289.42
293.47
301.43
307.94
313.41
1.886
1.467
1.200
0.978
0.852
0.776
0.629
0.508
0.406
47.90
37.25
30.48
24.84
21.63
19.72
15.97
12.90
10.32
29.121
23.548
19.734
16.397
14.439
13.250
10.862
8.863
7.151
43.337
35.044
29.368
24.402
21.487
19.718
16.164
13.189
10.641
388.62
7
9
11
13.5
15.5
17
21
26
32.5
10.67
11.70
12.35
12.90
13.21
13.39
13.76
14.05
14.30
270.92
297.08
313.72
327.59
335.47
340.16
349.39
356.93
363.27
2.186
1.700
1.391
1.133
0.987
0.900
0.729
0.588
0.471
55.52
43.18
35.33
28.79
25.07
22.86
18.51
14.95
11.96
39.124
31.637
26.513
22.030
19.398
17.801
14.593
11.907
9.607
58.223
47.081
39.456
32.784
28.868
26.491
21.717
17.720
14.296
441.96
7
9
11
13.5
15.5
17
21
26
32.5
12.13
13.30
14.05
14.67
15.02
15.23
15.64
15.98
16.26
308.11
337.85
356.78
372.56
381.51
386.84
397.34
405.92
413.13
2.486
1.933
1.582
1.289
1.123
1.024
0.829
0.669
0.535
63.14
49.11
40.18
32.74
28.51
26.00
21.05
17.00
13.60
50.601
40.917
34.290
28.492
25.089
23.023
18.874
15.400
12.425
75.303
60.892
51.030
42.401
37.336
34.262
28.087
22.918
18.490
495.30
7
9
11
13.5
15.5
17
21
26
32.5
13.59
14.91
15.74
16.44
16.83
17.07
17.53
17.91
18.23
345.29
378.63
399.84
417.52
427.56
433.53
445.30
454.91
462.99
2.786
2.167
1.773
1.444
1.258
1.147
0.929
0.750
0.600
70.76
55.03
45.03
36.69
31.95
29.14
23.59
19.05
15.24
63.553
51.390
43.067
35.785
31.510
28.916
23.704
19.342
15.605
94.577
76.477
64.091
53.253
46.892
43.031
35.276
28.784
23.223
548.64
7
9
11
13.5
15.5
17
21
26
32.5
15.06
16.51
17.44
18.21
18.65
18.91
19.42
19.84
20.19
382.48
419.40
442.90
462.48
473.60
480.22
493.25
503.90
512.85
3.086
2.400
1.964
1.600
1.394
1.271
1.029
0.831
0.665
78.38
60.96
49.88
40.64
35.40
32.27
26.13
21.10
16.88
77.978
63.055
52.842
43.907
38.662
35.479
29.085
23.732
19.147
116.044
93.836
78.638
65.341
57.536
52.799
43.283
35.317
28.494
A-10
PolyPipe 12/05
Table A-4 (cont'd)
PE3408 (BLACK)
OD
Nominal
in.
24
30
Nominal ID
Actual
in.
mm.
25.800
32.000
655.32
812.80
Minimum Wall
SDR
Weight
in.
mm.
in.
mm.
lb. per
foot
kg. per
meter
11
13.5
15.5
17
21
26
32.5
20.83
21.75
22.27
22.58
23.20
23.70
24.12
529.02
552.41
565.69
573.60
589.16
601.89
612.57
2.345
1.911
1.665
1.518
1.229
0.992
0.794
59.57
48.54
42.28
38.55
31.21
25.20
20.16
75.390
62.642
55.159
50.618
41.495
33.858
27.317
112.193
93.222
82.086
75.328
61.752
50.386
40.652
13.5
15.5
17
21
26
32.5
26.97
27.62
28.01
28.77
29.39
29.91
685.16
701.63
711.44
730.75
746.53
759.78
2.370
2.065
1.882
1.524
1.231
0.985
60.21
52.44
47.81
38.70
31.26
25.01
96.367
84.855
77.869
63.835
52.086
42.023
143.409
126.278
115.882
94.997
77.513
62.538
A-11
PolyPipe 12/05
PRESSURE DESIGN
A pipeline is defined as “a line of pipes for conveying water, gas, oil, etc.” These lines may operate at a positive
pressure, negative pressure or atmospheric pressure in the performance of their design parameters. A piping
system is acted upon by a multitude of design considerations: corrosion, ground entrained water, stray electromagnetic currents, external loads by soil, water table, and wave and/or current action, thermal changes and the
effects of ultraviolet light.
INTERNAL PRESSURE
PolyPipe® for industrial-municipal-mining applications is manufactured to specific dimensions as required in
applicable American Society for Testing and Materials (ASTM) standards. Piping outside diameters may meet the
IPS, DIPS or Metric systems. Wall thickness is based on the Dimension Ratio (DR) system, a specific ratio of the
nominal outside diameter to the minimum specified wall thickness. Use of the DR number in the ISO equation,
recognized as an equation depicting the relationship of pipe dimensions, both wall and OD, internal pressure
carrying capabilities and tensile stress, in conjunction with a suitable design factor (DF) will give the design
engineer confidence the pipe will not fail prematurely due to internal pressurization.
To move a material along a pipeline, forces of gravity, or internal pressure, differentials are required. For
atmospheric systems (gravity flow), gravitational forces provide the impetus for movement of heavier-than-air mass.
To move the same against gravity (pressure flow) additive internal forces are generated, which must be recognized
in the design stage in order to provide desired operational life. In some cases a gravity flow system must be
treated comparable to the design consideration of a pressure flow system.
®
2
Calculations for determining the internal pressure rating of PolyPipe are based on the ISO equation , which is:
P=
Where
P
HDB
DR
D
t
DF
=
=
=
=
=
=
2 ⋅ HDB
⋅ DF
(DR − 1)
(1)
Internal pressure, psi
Hydrostatic Design Basis, (1600 psi for PE3408)
Pipe dimension ratio (D/t)
Outside diameter, inches
Minimum wall thickness, inches
Design factor (0.5 for water @ 73oF (23oC))
Use of additional factors will provide for a more defined performance characteristic for systems with higher
operation temperatures, shorter operational time and system fluid other than water. These additional factors are
defined as the following:
•
•
•
F1 - Factor used where the operational life is less than 50 years. Refer to Figure A-1.
F2 - Temperature correction factor for service other than 73oF (23oC). Refer to Figure A-2.
F3 - Environmental factor utilized to compensate for the effect of substances other than water. Refer to
Table A-5.
With the implementation of additional factors, the ISO equation 2 now becomes:
P=
2
2 ⋅ HDB
⋅ DF ⋅ F1 ⋅ F2 ⋅ F3
(DR − 1)
(2)
ASTM D1598-97. Standard Test Method for Time-to-Failure of Plastic Under Constant Internal Pressure. Volume 8.04. American Society of
Testing and Materials. Baltimore, 2004.
A-12
PolyPipe 12/05
Where
P
HDB
DR
D
t
DF
F1
F2
F3
=
=
=
=
=
=
=
=
=
Internal pressure, psi
Hydrostatic Design Basis, (1600 psi for PE3408)
Pipe dimension ratio (D/t)
Minimum wall thickness, inches
Design factor (0.5 for water @ 73oF (23oC))
Operational life factor (Figure A-1)
Temperature correction factor (Figure A-2)
Environmental service factor (Table A-5)
Table A-5
ENVIRONMENTAL SERVICE FACTOR, F3
Substance
Service Factor, F3
Crude Oil
Wet Natural Gas
Federally Regulated Dry Natural Gas
0.50
0.50
0.64
It should be noted the maximum recommended service temperatures, under continuous pressure service, for
PolyPipe® is 150ºF (66ºC). However, for a non-pressure application, temperatures as high as 180ºF (82ºC) can be
considered. In such cases, consult your PolyPipe® supplier for additional design assistance.
Note: Compressed air service (greater than atmospheric pressure) can significantly shorten service life at
temperatures above 73°F. PolyPipe® does not recommend its’ product for compressed air service for a service life
greater than 5 years at 100oF. Further, PolyPipe® recommends all polyethylene piping in use for air service be
buried. Refer to Recommendation “B”, published by PPI, for further information regarding the use of polyethylene
piping for compressed air service.
Critical Buckling
In the design of a polyethylene piping system, external fluid pressure and/or internal vacuum may be treated
comparably. In a non-supported application collapse of the pipe may be calculated from the equation 1:
3
⎛ 2 E ⎞⎛ t ⎞
⎜
⎟⎟ ⋅ SF
P=⎜
2 ⎟⎜
⎝ 1 − v ⎠⎝ ( D − t ) ⎠
Where
P
E
D
t
ν
SF
=
=
=
=
=
=
(3)
Critical buckling pressure, psi
Modulus of elasticity, psi
Wall thickness, inches
Poisson’s ratio, dimensionless
Safety Factor
This provides resistance to forces created by external fluid pressure and/or internal vacuum that may start collapse
of a polyethylene pipe. Use of the long-term modulus of elasticity, 30,000 psi, instead of the instantaneous value of
125,000 psi, provides for a method of determining long-term distortion free operation. This calculation is accurate
for thin wall pipes and becomes progressively more conservative for thicker walls. The values shown in Table A-7
on pages A-16 and A-17 were obtained empirically. Further information on earthloading is given in Section C.
1
th
Nayyar, Mohinder L. Ed. Piping Handbook. 6 Edition. New York: McGraw-Hill, Inc., 1992.
A-13
PolyPipe12/05
A-14
PolyPipe 12/05
Table A-6
INTERNAL PRESSURE RATINGS FOR POLYPIPE®
DR
Temp.,
°F / °C
Life
Yrs.
1
2
5
50°/10°
10
20
50
1
2
5
75°/23°
10
20
50
1
2
5
100°/38°
10
20
50
1
2
5
125°/52°
10
20
50
7
7.3
9
9.3
11
13.5
15.5
17
21
26
32.5
368
2.54
359
2.48
347
2.39
340
2.34
330
2.28
317
2.19
351
2.42
342
2.36
331
2.28
323
2.23
314
2.17
302
2.08
276
1.90
269
1.86
260
1.79
255
1.76
248
1.71
238
1.64
266
1.83
259
1.79
251
1.73
245
1.69
239
1.65
229
1.58
221
1.52
215
1.48
208
1.43
204
1.41
198
1.37
190
1.31
177
1.22
172
1.19
167
1.15
163
1.12
158
1.09
152
1.05
152
1.05
149
1.03
144
0.99
141
0.97
137
0.94
131
0.90
138
0.95
135
0.93
130
0.90
127
0.88
124
0.86
119
0.82
110
0.76
108
0.74
104
0.72
102
0.70
99
0.68
95
0.66
88
0.61
86
0.59
83
0.57
81
0.56
79
0.54
76
0.52
70
0.48
68
0.47
66
0.46
65
0.45
63
0.43
60
0.41
psi
MPa
psi
MPa
psi
MPa
psi
MPa
psi
MPa
psi
MPa
309
2.13
302
2.08
292
2.01
285
1.97
277
1.91
267
1.84
295
2.03
287
1.98
278
1.92
272
1.88
264
1.82
254
1.75
232
1.60
226
1.56
219
1.51
214
1.48
208
1.43
200
1.38
224
1.54
218
1.50
211
1.46
206
1.42
200
1.38
193
1.33
186
1.28
181
1.25
175
1.21
171
1.18
166
1.14
160
1.10
148
1.02
145
1.00
140
0.97
137
0.94
133
0.92
128
0.88
128
0.88
125
0.86
121
0.83
118
0.81
115
0.79
110
0.76
116
0.80
113
0.78
109
0.75
107
0.74
104
0.72
100
0.69
93
0.64
90
0.62
88
0.61
86
0.59
83
0.57
80
0.55
74
0.51
72
0.50
70
0.42
68
0.47
67
0.46
64
0.44
59
0.41
57
0.39
56
0.39
54
0.37
53
0.37
51
0.35
psi
MPa
psi
MPa
psi
MPa
psi
MPa
psi
MPa
psi
MPa
251
1.73
244
1.68
236
1.63
231
1.59
225
1.55
216
1.49
239
1.65
233
1.61
225
1.55
220
1.52
214
1.48
206
1.42
188
1.30
183
1.26
177
1.22
173
1.19
168
1.16
162
1.12
181
1.25
177
1.22
171
1.18
167
1.15
162
1.12
156
1.08
150
1.03
147
1.01
142
0.98
139
0.96
135
0.93
130
0.90
120
.083
117
0.81
113
0.78
111
0.7
108
0.74
104
0.72
104
0.72
101
0.70
98
0.68
96
0.66
93
0.64
89
0.61
94
0.65
92
0.63
89
0.61
87
0.60
84
0.58
81
0.56
75
0.52
73
0.50
71
0.49
69
0.48
67
0.46
65
0.45
60
0.41
59
0.41
57
0.39
55
0.38
54
0.37
52
0.36
48
0.33
47
0.32
45
0.31
44
0.30
43
0.30
41
0.28
psi
MPa
psi
MPa
psi
MPa
psi
MPa
psi
MPa
psi
MPa
192
1.32
187
1.29
181
1.25
177
1.22
172
1.19
165
1.14
183
1.26
178
1.23
172
1.19
168
1.16
164
1.13
157
1.08
144
0.99
140
0.97
136
0.94
133
0.92
129
0.89
124
0.86
139
0.96
135
0.93
131
0.90
128
0.88
124
0.86
120
0.83
115
0.79
112
0.77
109
0.75
106
0.73
103
0.71
99
0.68
92
0.63
90
0.62
87
0.60
85
0.59
83
0.57
79
0.54
79
0.54
77
0.53
75
0.52
73
0.50
71
0.49
68
0.47
72
0.50
70
0.48
68
0.47
66
0.46
64
0.44
62
0.43
58
0.40
56
0.39
54
0.37
53
0.37
52
0.36
50
0.34
46
0.32
45
0.31
43
0.30
42
0.29
41
0.28
40
0.28
37
0.26
36
0.25
34
0.23
34
0.23
33
0.23
31
0.21
psi
MPa
psi
MPa
psi
MPa
psi
MPa
psi
MPa
psi
MPa
Note: Tables for internal and external pressure ratings for PE3408 are based on gases and liquids that are non-aggressive to the
®
polyethylene. For further information on chemical resistance of PolyPipe , see Section E, "Chemical Resistance."
A-15
PolyPipe 12/05
Table A-6 (cont)
INTERNAL PRESSURE RATINGS FOR POLYPIPE®
DR
Temp.,
°F / °C
Life,
years
1
2
5
140°/60°
10
20
50
7
7.3
9
9.3
11
13.5
15.5
17
21
26
32.5
156
1.08
151
1.04
147
1.01
142
0.98
140
0.97
134
0.92
148
1.02
144
0.99
139
0.96
135
0.93
132
0.91
127
0.88
117
0.81
113
0.78
110
0.76
106
0.73
104
0.72
100
0.69
113
0.78
110
0.76
106
0.73
103
0.71
101
0.70
97
0.67
93
0.64
90
0.62
88
0.61
85
0.59
83
0.57
80
0.55
75
0.52
72
0.50
70
0.48
68
0.47
67
0.46
64
0.44
64
0.44
62
0.43
60
0.41
58
0.40
57
0.40
55
0.38
58
0.40
57
0.39
55
0.38
53
0.37
52
0.36
50
0.35
47
0.32
45
0.31
44
0.30
43
0.30
42
0.29
40
0.28
37
0.26
36
0.25
35
0.24
34
0.23
33
0.23
32
0.22
30
0.21
29
0.20
29
0.20
28
0.19
27
0.19
26
0.18
psi
MPa
psi
MPa
psi
MPa
psi
MPa
psi
MPa
psi
MPa
Table A-7
EXTERNAL PRESSURE RATINGS FOR POLYPIPE®
(for non-supported application)
DR
Temp.,
°F / °C
Life,
years
Day
Month
Year
50°/10°
2 Years
5 Years
10 Years
50 Years
Day
Month
Year
75°/23°
2 Years
5 Years
10 Years
50 Years
7
7.3
9
9.3
11
13.5
15.5
17
21
26
32.5
221.1
1.52
154.0
1.06
132.
0.91
123.2
0.85
117.7
0.81
114.4
0.79
110.0
0.76
201.0
1.39
140.0
0.97
120.0
0.83
112.0
0.77
107.0
0.74
104.0
0.72
100.0
0.68
150.7
1.04
105.0
0.72
90.0
0.62
84.0
0.58
80.6
0.55
78.0
0.54
75.0
0.52
142.7
0.98
99.4
0.69
85.2
0.59
79.5
0.55
76.0
0.52
73.8
0.51
71.0
0.49
110.6
0.76
77.0
0.53
66.0
0.46
61.6
0.42
58.9
0.41
57.2
0.39
55.0
0.38
68.3
0.47
47.6
0.33
40.8
0.28
38.1
0.26
36.4
0.25
35.5
0.24
34.0
0.23
48.2
0.33
33.6
0.23
28.8
0.20
26.9
0.19
25.7
0.18
25.0
0.17
24.0
0.17
28.1
0.19
19.6
0.14
16.8
0.12
15.7
0.11
15.0
0.10
14.6
0.10
14.0
0.10
14.1
0.10
9.8
0.07
8.4
0.06
7.8
0.05
7.5
0.05
7.3
0.05
7.0
0.05
8.0
0.06
5.6
0.04
4.8
0.03
4.5
0.03
4.3
0.03
4.2
0.03
4.0
0.03
4.0
0.03
2.8
0.02
2.4
0.02
2.2
0.02
2.1
0.01
2.1
0.01
2.0
0.01
psi
MPa
psi
MPa
psi
MPa
psi
MPa
psi
MPa
psi
MPa
psi
MPa
176.0
1.22
123.2
0.85
105.6
0.73
98.6
0.68
94.2
0.65
91.5
0.63
88.0
0.61
164.8
1.14
114.8
0.79
98.4
0.68
91.8
0.63
87.7
0.60
85.3
0.59
82.0
0.57
134.7
0.93
93.8
0.65
80.4
0.55
75.0
0.52
71.7
0.49
69.7
0.48
67.0
0.46
124.6
0.86
86.8
0.60
74.4
0.51
69.4
0.48
66.3
0.46
64.5
0.44
62.0
0.43
98.5
0.68
68.6
0.47
58.8
0.41
54.9
0.38
52.4
0.36
51.0
0.35
49.0
0.34
60.3
0.42
42.0
0.29
36.0
0.25
33.6
0.23
32.1
0.22
31.2
0.22
30.0
0.21
42.2
0.29
29.4
0.20
25.2
0.17
23.5
0.16
22.5
0.16
21.8
0.15
21.0
0.14
24.1
0.17
16.8
0.12
14.4
0.10
13.4
0.09
12.8
0.09
12.5
0.09
12.0
0.08
13.1
0.09
9.1
0.06
7.8
0.05
7.3
0.05
7.0
0.05
6.8
0.05
6.5
0.04
7.0
0.05
4.9
0.03
4.2
0.03
3.9
0.03
3.7
0.03
3.6
0.02
3.5
0.02
3.6
0.02
2.5
0.02
2.2
0.02
2.0
0.01
1.9
0.01
1.9
0.01
1.8
0.01
psi
MPa
psi
MPa
psi
MPa
psi
MPa
psi
MPa
psi
MPa
psi
MPa
Note: Tables for internal and external pressure ratings for PE3408 are based on gases and liquids that are non-aggressive to the polyethylene.
®
For further information on chemical resistance of PolyPipe , see Section E, "Chemical Resistance."
A-16
PolyPipe 12/05
Table A-7 (cont)
EXTERNAL PRESSURE RATINGS FOR POLYPIPE®
DR
Temp.,
°F / °C
Life,
years
Day
Month
Year
100o/38°
2 Years
5 Years
10 Years
50 Years
Day
Month
Year
125°/52°
2 Years
5 Years
10 Years
50 Years
Day
Month
Year
150°/65°
2 Years
5 Years
10 Years
50 Years
7
7.3
9
9.3
11
13.5
15.5
17
21
26
32.5
152.8
1.05
106.4
0.73
91.2
0.63
85.1
0.59
81.3
0.56
79.0
0.54
76.0
0.52
140.7
0.97
98.0
0.68
84.0
0.58
78.4
0.54
74.9
0.52
72.8
0.50
70.0
0.48
110.6
0.76
77.0
0.53
66.0
0.46
61.6
0.42
58.9
0.41
57.2
0.39
55.0
0.38
104.5
0.72
72.8
0.50
62.4
0.43
58.2
0.40
55.6
0.38
54.1
0.37
52.0
0.36
82.4
0.57
57.4
0.40
49.2
0.34
45.9
0.32
43.9
0.30
42.6
0.29
41.0
0.28
48.2
0.33
33.6
0.23
58.8
0.20
26.9
0.19
25.7
0.18
25.0
0.17
24.0
0.17
34.2
0.24
23.8
0.16
20.4
0.14
19.0
0.13
18.2
0.13
17.7
0.12
17.0
0.12
20.1
0.14
14.0
0.10
12.0
0.08
11.2
0.08
10.7
0.07
10.4
0.08
10.0
0.07
10.1
0.07
7.0
0.05
6.0
0.04
5.6
0.04
5.4
0.04
5.2
0.04
5.0
0.03
6.0
0.04
4.2
0.03
3.6
0.02
3.4
0.02
3.2
0.02
3.1
0.02
3.0
0.02
3.0
0.02
2.1
0.01
1.8
0.01
1.7
0.01
1.6
0.01
1.6
0.01
1.5
0.01
psi
MPa
psi
MPa
psi
MPa
psi
MPa
psi
MPa
psi
MPa
psi
MPa
120.6
0.83
84.0
0.58
72.0
0.50
67.2
0.46
62.4
0.44
62.4
0.43
60.0
0.41
108.5
0.75
75.6
0.52
64.8
0.45
60.5
0.42
57.8
0.40
56.2
0.39
54.0
0.37
88.4
0.61
61.6
0.42
52.8
0.36
49.3
0.34
47.1
0.32
48.8
0.34
44.0
0.30
82.4
0.57
57.4
0.40
49.2
0.34
45.9
0.32
43.9
0.30
42.6
0.29
41.0
0.58
68.3
0.47
47.6
0.33
40.8
0.28
38.1
0.26
36.4
0.25
35.4
0.24
34.0
0.23
38.2
0.26
26.6
0.18
22.8
0.16
21.3
0.15
20.3
0.14
19.8
0.14
19.0
0.13
26.1
0.18
18.2
0.13
15.6
0.11
14.6
0.10
13.9
0.10
13.5
0.09
13.0
0.09
16.1
0.11
11.2
0.08
9.6
0.07
9.0
0.06
8.6
0.06
8.3
0.06
8.0
0.06
9.0
0.06
6.3
0.04
5.4
0.04
5.0
0.03
4.8
0.03
4.7
0.03
4.5
0.03
4.6
0.03
3.2
0.02
2.8
0.02
2.6
0.02
2.5
0.02
2.4
0.02
2.3
0.02
2.4
0.02
1.7
0.01
1.4
0.01
1.3
0.01
1.3
0.01
1.2
0.01
1.2
0.01
psi
MPa
psi
MPa
psi
MPa
psi
MPa
psi
MPa
psi
MPa
psi
MPa
104.5
0.72
72.8
0.50
62.4
0.43
58.2
0.40
55.6
0.38
54.1
0.37
52.0
0.36
94.5
0.65
65.8
0.45
56.4
0.39
52.6
0.36
50.3
0.35
48.9
0.34
47.0
0.32
76.4
0.53
53.2
0.37
45.6
0.31
42.6
0.29
40.7
0.28
39.5
0.27
38.0
0.26
72.4
0.50
50.4
0.35
43.2
0.30
40.3
0.28
38.5
0.27
37.4
0.26
36.0
0.25
58.3
0.40
40.6
0.28
34.8
0.24
32.5
0.22
31.0
0.21
30.2
0.21
29.0
0.20
32.2
0.22
22.4
0.15
19.2
0.13
17.9
0.12
17.1
0.12
16.6
0.11
16.0
0.11
22.1
0.15
15.4
0.11
13.2
0.09
12.3
0.08
11.8
0.08
11.4
0.08
11.0
0.08
14.1
0.10
9.8
0.07
8.4
0.06
7.8
0.05
7.5
0.05
7.3
0.05
7.0
0.05
7.4
0.05
5.2
0.04
4.4
0.03
4.1
0.03
4.0
0.03
3.8
0.03
3.7
0.06
4.0
0.03
2.8
0.02
2.4
0.02
2.2
0.02
2.1
0.01
2.1
0.01
2.0
0.01
2.0
0.01
1.4
0.01
1.2
0.01
1.1
0.01
1.1
0.01
1.0
0.01
1.0
0.01
psi
MPa
psi
MPa
psi
MPa
psi
MPa
psi
MPa
psi
MPa
psi
MPa
Note: Tables for internal and external pressure ratings for PE3408 are based on gases and liquids that are non-aggressive to the polyethylene.
®
For further information on chemical resistance of PolyPipe , see Section E, "Chemical Resistance."
A-17
PolyPipe 12/05
VACUUM OR EXTERNAL PRESSURE SYSTEM
A piping system can be subjected to a positive external pressure or vacuum as opposed to the more usual positive
internal pressure situation. In most cases this occurs by design, as in a water suction line, but it can also occur in
an unexpected manner. For instance, a system that has a high point in the down slope side of the pipeline can
result in a flow velocity greater than the velocity on the uphill side.
In other applications, there may be both vacuum and external pressure applied to the system. This condition can
occur if a pump suction line is buried with significant external load above the top of the pipe. Both of these factors
are additive and should be considered in the design of the piping system.
In either situation, the effects of external pressure or vacuum conditions must be considered in the design. Pipe
buckling can occur in extreme cases, but can be prevented by correctly designing the system. In the event that
buckling should occur, it is generally not a catastrophic failure. Buckling occurs as a gradual deflection of the pipe
to an out-of-round condition that will progressively worsen to the point of becoming totally flat. Since buckling
occurs without cracking or splitting the pipe wall, the pipe can be restored to its original round condition. This can
be accomplished by applying an internal pressure for a short period of time. The cause of the buckling should be
identified and corrected.
®
Safe external pressures for PolyPipe are given in Table A-7 for a series of temperatures. These values are
based on various life expectancies for applications using water or fluids having similar compatibility with
polyethylene.
In some situations, vacuums and/or external loads occur for a relatively short duration. By estimating the duration
of the load and applying the time correction factors, Table A-8, the designer may match the pipe DR (Dimension
Ratio) to the particular application. Thinner wall pipe is usually capable of handling short duration loads. These
time correction factors are used in the calculation of the values represented in Table A-7 on pages A-16 and A-17.
External loading is explained in more detail in Section C.
Table A-8
TIME CORRECTION FACTOR
Time
Time Correction Factor
Day
Month
Year
2 Years
5 Years
10 Years
50 Years
2.01
1.40
1.20
1.12
1.07
1.04
1.00
Example: Calculate the external pressure for DR 26 pipe for one-month duration with an estimated 4.0 psi (0.02
Mpa) external pressure at 75oF (23oC).
From Table A-7, external pressure at 50 years is 3.5 psi (0.02 MPa) x time correction factor, 1.40 = 4.90 psi (0.03
MPa) capabilities.
NOTICE:
®
The data contained herein is a guide to the use of PolyPipe polyethylene pipe and fittings and is believed to be accurate
and reliable. However, general data does not adequately cover specific applications, and its suitability in particular
applications should be independently verified. In all cases, the user should assume that additional safety measures might
be required in the safe installation or operation of the project. Due to the wide variation in service conditions, quality of
installation, etc., no warranty or guarantee, expressed or implied, is given in conjunction with the use of this material.
A-18
PolyPipe 12/05
FLUID FLOW
The rate at which fluid flows through a piping system is an important factor in designing the system. Factors
affecting fluid flow can include the following: density, pressure (including pressure loss), inside diameter of the
pipe, and any additional resistance factors within the system such as fittings.
PolyPipe® has an extremely smooth inside surface resulting in a very low coefficient of friction and a minimal loss
of head pressure due to frictional losses as compared to other piping materials. The inside surface experiences
virtually no deterioration due to corrosion. Beneficial properties of the smooth bore of the polyethylene pipe are
maintained throughout its service life. In view of these advantages, it is often possible to utilize a polyethylene pipe
of a smaller inside diameter than other piping products.
The maximum allowable water velocity in a thermoplastic piping system is a function of the design of a specific
system and its operating conditions. Per PPI Technical Report #14, “In general, design velocities of 5 - 10 feet/sec
are considered to be normal.” As noted, these velocities are recommended for water and will vary depending on
the fluid medium and inside diameter of the pipe. Recommended velocities for different fluid properties are given
below in Table B-1. Additional information for slurry type applications is addressed in Section H.
Table B-1
RECOMMENDED LIQUID VELOCITIES
Recommended Velocity
Water and Similar Viscous Liquids
Viscous Liquids
Pipe Size
Pump
Suction*
Pump
Discharge
Gravity Drain
System
Pump
Suction*
Pump
Discharge
3 - 10 inches
(76 - 254 mm)
1 - 4 feet/sec
(30 - 122 cm/sec)
3 – 10 feet/sec
(91 - 300 cm/sec)
3 - 5 feet/sec
(91 - 152 cm/sec)
.05 - 2 feet/sec
(15 - 61 cm/sec)
3 - 5 feet/sec
(91 - 152 cm/sec)
10 - 28 inches
(254 - 711 mm)
3 - 6 feet/sec
(91 - 183 cm/sec)
4 – 10 feet/sec
(122 - 400 cm/sec)
4 - 8 feet/sec
(122 - 244 cm/sec)
1 - 4 feet/sec
(30 - 122 cm/sec)
4 - 6 feet/sec
(122 - 183 cm/sec)
28 - 54 inches
(711 - 1372 mm)
5 - 8 feet/sec
(152 - 244 cm/sec)
6 - 12 feet/sec
(183 - 366 cm/sec)
6 - 10 feet/sec
(183 - 305 cm/sec)
2 - 5 feet/sec
(61 - 152 cm/sec)
5 - 7 feet/sec
(152 - 213 cm/sec)
*It is important in the selection of the pipe size that the designated pump suction velocity be lower than the
discharge velocity.
B-1
PolyPipe 12/05
PRESSURE DROP
A fluid is defined as "a substance which when in static equilibrium cannot sustain tangential or shear forces."
Three types of forces that may act on a body are shear, tensile and compressive. Shear and tensile forces on
fluids are not addressed in this Guide. Compressive forces, which result in pressure, are considered due to the
importance in the design of piping system capabilities.
Volumetric flow, Q, can be determined from the continuity equation 4 = A • V. Modified for flow in gallons per
minute, this is:
Q = 2.448 ⋅ V ⋅ d 2
(4)
or
d=
Where
Q
V
d
=
=
=
Q
2.448 ⋅ V
(5)
Volumetric flow, gpm
Velocity, ft/sec
Inside diameter, inches
EXAMPLE: If the required water flow rate for a system is 2000 gpm and the flow velocity is to be maintained below
8 ft/s, what is the pipe diameter?
d=
2000
= 10.1 inches
2.448 ⋅ 8
FRICTIONAL PRESSURE LOSS
The total pressure drop in a system is the sum of pressure losses due to friction, fittings and elevation changes.
Pressure loss due to friction in the pipe is calculated using the Hazen-Williams formula 1. This applies to systems
pumping water and fluids of like viscosities. The Hazen-Williams formula is:
ΔPf =
Where
453 ⋅ Q 1.85
C 1.85 ⋅ d 4.86
ΔPf
=
Pressure loss due to friction, psi per 100 feet
C
Q
d
=
=
=
Hazen-Williams Flow Factor Coefficient*
Volumetric flow rate, gpm
(6)
*PolyPipe® recommends a value of 150 for C based upon information from Plastics Pipe Institute Technical
Report #14, Water Flow Characteristics of Thermoplastic Pipe. For further information, please reference this article
(www.plasticpipe.org).
It should be noted the pipe sizes quoted in the figures are minimum bore sizes and the specific outside diameter of
the pipe can be found from the pipe dimensions located in Section A.
The Hazen-Williams formula can be used to calculate any one of the following variables: volumetric flow rate (Q),
velocity (V), inside pipe diameter (d) or frictional pressure loss (ΔPf). Additional values for Hazen-Williams Flow
Factor Coefficients are shown in Table B-2.
4
1
Larock, B.E., Jeppson, R.W. , Watters, G.Z. Hydraulics of Pipeline Systems. Boca Raton: CRC Press, 2000.
th
B-2
PolyPipe 12/05
Table B-2
HAZEN-WILLIAMS COEFFICIENTS FOR FLOW IN VARIOUS PIPES
PIPE DESCRIPTION
"C" VALUE
PolyPipe® HDPE
Very smooth and straight steel, glass
New cement-lined ductile iron
Smooth wood and wood stave
New riveted steel, cast iron
Old cast iron
Old pipes in bad condition
Small pipes, badly corroded
150
130-140
130
120
110
95
60-80
40-50
ELEVATION PRESSURE LOSS/GAIN
The Hazen-Williams formula is used to establish only the pressure losses due to friction in the pipe. If there is a
change in elevation, it is necessary to calculate the change in pressure due to elevation changes. The change in
pressure may be either a positive change (downhill) or negative (uphill).
In a line with an elevation change without a change in pipe diameter, the pressure loss can be calculated as
follows:
ΔPe = ρ
Where
ΔPe
h2
h1
ρ
=
=
=
=
(h2 − h1 )
(7)
144
Change in pressure due to elevation change, psi
High point elevation, feet
Low point elevation, feet
Density of fluid, lbs/ft3
PRESSURE LOSS IN FITTINGS
Any calculation of the pressure drop in a piping system cannot be made accurately without consideration of the
loss in pressure due to the presence of fittings in the system.
The fluid flow, when encountering a fitting, is subjected to change in direction and the resultant degree of initiation
of turbulence, or at least an interruption in the desirable steady flow condition which exists in the straight run of
pipe, is an increase in head loss or pumping pressure.
Due to the geometry and variance in flow conditions through the fitting, the exact pressure loss cannot be
calculated in any practical sense. The pressure loss is calculated by expressing the fitting as an equivalent length
of pipe expected to produce the same pressure loss. The values shown in Table B-3 have been derived to some
extent by experimentation, but are to a greater extent the result of a general industry consensus (PPI Technical
Report #14).
B-3
PolyPipe 12/05
Table B-3
PRESSURE DROP IN FITTINGS
TYPE OF FITTING
EQUIVALENT LENGTH OF PIPE*, ft
90° Elbow, molded
90° Elbow, mitered
60° Elbow
45° Elbow, molded
45° Elbow, mitered
Running Tee
Branch Tee
Gate Valve, full open
Butterfly Valve 3”-14” (76-356 mm)
114” (356 mm) and larger
Swing Check Valve
Ball Valve, full bore, full open
16D
24D
16D
16D
12D
20D
60D
8D
40D
30D
100D
3D
*NOTE: D is the inside diameter of the pipe in feet.
EXAMPLE: A running tee has an equivalent length of 20D. For an 18” (457 mm) DR11 line, calculate the
equivalent length of pipe for the fitting to account for the pressure loss.
From page A-6, the nominal inside diameter of 18” DR11 is 14.60 inches. 14.60” x 20 = 292 inches or 24.3 feet
Therefore, a total of 24.3 feet is added to the total line length to account for the additional pressure loss created by
the fitting.
TOTAL PRESSURE LOSS
The total pressure required to maintain the flow rate can be calculated by summing pressure losses calculated
using the Hazen-Williams for frictional pressure loss in the pipe, Equation (7) for elevation changes and Table B-3
for fitting pressure losses.
ΔPT = ΔPf + ΔPe + ΔPfittings
(8)
B-4
PolyPipe 12/05
GRAVITY FLOW
The Manning equation 1 is the most commonly accepted approximation for gravity flow.
1.486 ⋅ R 0.667 ⋅ S 0.5
V =
n
Where
V
R
S
n
=
=
=
=
(9)
Average flow velocity, ft/sec
Hydraulic radius, feet
Slope of pipe, feet per foot
Manning flow coefficient, 0.010
®
The Manning flow coefficient (n) for PolyPipe
approximation generally used is 0.010.
is approximately 0.009.
However, a reliable, conservative
The hydraulic radius can be determined from the following formula:
(10)
R = f ⋅d
Where
h
ID
0.05
0.10
0.15
0.20
0.25
0.30
0.35
0.40
0.45
0.50
R
f
d
=
=
=
Hydraulic radius, feet
Fullness factor
Inside diameter, feet
Table B-4
FULLNESS FACTORS
h
A
ID
0.0147
0.55
0.0409
0.60
0.0739
0.65
0.1118
0.70
0.1535
0.75
0.1982
0.80
0.2450
0.85
0.2934
0.90
0.3428
0.95
0.3927
1.00
f
0.0326
0.0636
0.0929
0.1206
0.1466
0.1710
0.1935
0.2143
0.2331
0.2500
f
A
0.2649
0.2776
0.2881
0.2962
0.3017
0.3042
0.3033
0.2980
0.2864
0.2500
0.4426
0.4920
0.5404
0.5872
0.6319
0.6736
0.7115
0.7445
0.7707
0.7854
Once the flow velocity has been determined, the volumetric flow rate can be calculated by use of the following
formula:
Q = V ⋅ A⋅d 2
1
th
(11)
B-5
PolyPipe 12/05
Where
Q
V
d
A
=
=
=
=
Volumetric flow rate, ft3/sec
Velocity, ft/sec
Area factor from Table B-4
or
Q = 449 ⋅ V ⋅ A ⋅ d 2
Where
Q
=
(12)
For full flow applications, the volumetric flow rate can be determined by use of the following formula:
Q=
Where
Q
n
d
S
=
=
=
=
0.275 2.667 0.5
⋅d
⋅S
n
(13)
Manning coefficient, 0.010
Slope, feet per foot
B-6
PolyPipe 12/05
PRESSURE SURGE AND WATER HAMMER
Widespread usage of polyethylene pipe in liquid flow necessitates a better understanding of actions and reactions
in mass flow that could affect the system. As water is a liquid, and at substantial velocities almost acts like a solid,
it behaves in a complex manner when accelerating or decelerating.
This moving water column inside a pipe has available active kinetic energy. This energy can be calculated from its
mass and velocity. A change in the column velocity causes an energy change that manifests itself as a pressure
change. This pressure change, or surge pressure, is commonly known as "water hammer." Water hammer is
better described as hydraulic transient pressure and is a sudden increase or decrease in pressure due to changes
in the velocity of flowing fluid in a pipeline.
Air entrained in a piping system over normal rolling terrain can cause water hammer. Even if proper filling
techniques are utilized and all air is displaced, entrained air will separate and collect in pockets in the "humps" in
the pipeline. Significant pressures are generated when the air pockets are suddenly released. The use of air relief
valves at the high points can alleviate this problem.
An abrupt blockage in a moving column of water creates an increase in pressure on the upstream side and a
negative pressure on the downstream side of the block. The magnitude of these pressures is relative to the
velocity of the fluid, mass of the fluid and speed the blockage occurs.
The forces required to bring this column of water to rest are the forces for friction and the hoop stress imposed on
the pipe wall. Therefore, the stress in the pipe wall is increased by the magnitude of the surge and the total stress
is normal operating stress (pressure) plus the surge stress (pressure).
On the downstream side of a block the water column may create a vacuum. Depending on the velocity of the
column, it may separate and be drawn back together. Vacuum in this condition does not normally detrimentally
affect the pipe unless column separation does occur. In that case, extremely high positive pressures can be
generated when the void re-closes and the two column faces collide.
Water hammer in a piping system is a pressure wave that is set up due to a change in velocity of the liquid and the
wave may move through the column at a velocity of up to 4500 ft/sec, depending upon the piping material.
1
The magnitude, ΔP, of this pressure wave can be calculated from the following equation :
ΔP =
Where
ΔP
ΔV
g
ρ
S
=
=
=
=
=
ρ
144 ⋅ g
⋅ S ⋅ ΔV
(14)
Surge pressure, psi
Change in velocity, ft/sec
Acceleration due to gravity, 32.2 ft/sec2
Density of fluid, lb/ft3
Wave velocity, ft/sec
The value calculated by using Equation (14) may have either a resultant positive or negative pressure wave. This
resultant force, when superimposed on the existing operating pressure curve, will either decrease or increase from
the normal operating pressure.
Where S, the wave velocity, can be calculated by the following formula 1:
⎡
⎢
S=⎢
⎢ρ
⎢
⎣g
Where
1
E
=
⎤
⎥
E ⋅ E'
⎥
⎛
⎛ E '⋅d ⎞ ⎞ ⎥
⋅ ⎜⎜ E + ⎜
⎟ ⎟⎟ ⎥
⎝ t ⎠⎠⎦
⎝
1/ 2
(15)
Instantaneous modulus of elasticity of material, lbs/ft2
th
B-7
PolyPipe 12/05
=
=
=
=
=
E’
d
ρ
g
t
Bulk modulus of fluid, lbs/ft2
Density of fluid, lb/ft3
Acceleration due to gravity, 32.2 ft/sec2
Pipe wall thickness, feet
Due to the elastic properties of polyethylene, a significant amount of pressure surge is absorbed through
expansion. This elasticity provides for reduction of the shock wave initially and dissipation of the wave. Per AWWA
C-906, a system operating below the pressure class rating is capable of handling a surge capacity in accordance
with the following:
1. Recurring Pressure Surge: The total of the maximum working pressure and maximum recurring pressure
surge may be no greater than 1.5 times the pipe’s nominal pressure class (PC).
2. Occasional Pressure Surge: The total of the maximum working pressure and maximum occasional pressure
surge may be no greater than 2 times the pipe’s nominal pressure class (PC).
Since water hammer surges are produced due to a change in velocity, the proper control of valves may eliminate or
minimize this effect. In order to minimize or eliminate water hammer, the flow must not be shut off any faster than it
takes a pressure wave to be initiated at the beginning of valve closing and returning to the valve again. This by
1
definition is considered the critical time (Tcr) that is defined as the longest elapsed time before final flow stoppage
that still permits the maximum pressure to occur.
Tcr =
Where
Tcr
vs
L
=
=
=
2⋅L
vs
(16)
Propagation time, seconds
Speed of sound through commodity, ft/sec
Length of pipeline, feet
Since most valves do not cut off the flow rate proportionately to the valve-stem travel, it is significant to base timing
of valve closure on effective closing timing. The effective closing timing in most applications is determined as onehalf of the actual closing time. This is the value that should be used in water hammer calculations.
The most important aspect to recognize in the design of the system is to remember water hammer surge can occur
and methods of protecting the system and minimizing effect need to be addressed. This can be accomplished by
the installation of equipment including the following:
Pressure relief valves
Control closing check valves
Surge arrestors
Vacuum air relief valves
Surge tanks
Manually operated gate valves
In summary, surges are the result of a change in velocity within the system. This change in velocity is directly
related to the change in pressure for the system (negative or positive). Water hammer surges can be avoided by
eliminating sudden changes in velocity within the system. By taking the necessary precautionary steps during
initial filling and testing of the pipeline, a significant number of surge problems can be eliminated.
NOTICE:
®
The data contained herein is a guide to the use of PolyPipe polyethylene pipe and fittings and is believed to be accurate and
reliable. However, general data does not adequately cover specific applications, and its suitability in particular applications
should be independently verified. In all cases, the user should assume that additional safety measures might be required in the
safe installation or operation of the project. Due to the wide variation in service conditions, quality of installation, etc., no
warranty or guarantee, expressed or implied, is given in conjunction with the use of this material.
1
th
B-8
PolyPipe 12/05
EARTHLOADING
PolyPipe®, due to its flexibility, will deflect when it is buried. The degree of deflection will depend upon the soil
conditions, burial conditions, trench width, and the depth of burial. The degree of deflection of the pipe is limited by
the soil around its periphery, especially in the lateral direction. When the soil compacts around the pipe, there is a
supportive effect from the soil itself, and as compaction occurs, there is soil friction and cohesion over the pipe that
reduces the direct load on the pipe.
PolyPipe®, as do other flexible conduits, depends on the surrounding soil for support, and has to be considered as
one component in a pipe/soil system. The presence of the soil arch and the support derived from the lateral
movement limitations are highly beneficial to the efficiency of the system. Therefore, the flexibility of PolyPipe® is
the major reason for these advantages. As has been stated, the durability of polyethylene is the reason for its
resistance to high levels of mechanical abuse, and this is no less true for buried systems where forced deflections
may occur due to subsidence, washout and settlement.
External loading analysis must be conducted to determine the application's feasibility. There are two loading
calculations necessary when designing or engineering below ground applications of PolyPipe®. These calculations
are ring deflection and wall buckling. Wall crushing, calculated using the allowable compressive strength of the PE
material, is usually not critical when using solid wall PolyPipe®, as ring deflection and wall buckling are
predominant parameters.
RING DEFLECTION
PolyPipe®, when buried in loose soil conditions, will exhibit the tendency to deflect, called ring deflection. Listed
below are the recommended maximum allowable design limits for ring deflection of PolyPipe® for the different
available Dimension Ratios (DR).
Table C-1
Design Limits for Ring Deflection
Safe Deflection, % of
Diameter
8.0
7.0
6.0
5.0
DR
32.5
26
21
17
Figure C-1
W
ΔX
D
C-1
PolyPipe 12/05
PolyPipe®, due to its inherent physical properties of flexibility, resilience and toughness can withstand significant
deflection without failure. It can be flattened without causing a fracture of the pipe wall. However, this condition is
unacceptable as far as service is concerned. A deflection of 15% would be acceptable for a butt fused
polyethylene system, although a reduction in flow would be noted. It would also be difficult to utilize conventional
cleaning equipment with this severity of deflection. Ring deflection resulting in hydraulic flow area reductions
should be taken into account when engineering the flow characteristics. Refer to Table C-2 for the percentage of
area reduction based on percent of ring deflection.
Table C-2
AREA REDUCTION DUE TO RING DEFLECTION
Ring Deflection, %
Area Reduction, %
2
4
5
6
8
10
12
14
15
16
0.04
0.16
0.25
0.36
0.64
1.00
1.44
1.96
2.25
2.56
In calculating the soil load placed on a buried pipe, the designer must be able to calculate to some degree of
accuracy the type and condition of the backfill material. Saturated clay would be more difficult to place and
adequately compact than would coarse granular material that would not stick together. It is important in the
pipe/soil system that the backfill material utilized for haunching and initial backfill (see Installation, Section F, for
explanation of terminology) be granular and non-cohesive, free of debris, organic matter, frozen earth and rocks
larger than 1½ inch in diameter. This material can be described as Class I or II of ASTM D2321 "Angular ¼ to 1½
inch Graded Stone, Slag, Cinders, Crushed Shells and Stone or Sands and Gravel Containing Small Percentages
of Fines, Generally Granular and Non-Cohesive, Wet or Dry." This material can easily be worked into the pipe
haunch, and compacted in approximately 4-6 inch lifts.
®
To determine the ring deflection of externally loaded PolyPipe , you must first determine the earthload in pounds
per linear inch of pipe by use of the following modified Marston formula 5:
W=
Where
W
Cd
ρ
D
Bd
5
=
=
=
=
=
C d ⋅ ρ ⋅ Bd ⋅ D
144
(17)
Earthload per unit length of pipe, lbs/in
Trench Coefficient, (dimensionless) (See Figure C-2)
Soil density, lbs/ft3
Trench width at top of pipe, feet
Moser, A.P. Buried Pipe Design. 2nd Edition. New York: McGraw-Hill, 2001.
C-2
PolyPipe 12/05
Table C-3
CLASSIFICATION OF BACKFILL MATERIAL
PER ASTM D2321*
Class
Comments
Class I - Angular graded stone, ¼” to 1½”, including a number
of fill materials that have regional significance such as coral,
slag, cinders, crushed stone, crushed gravel and crushed
shells.
100 - 200 pounds per cubic foot. Pipe sizes less
than 10” should limit maximum particle size to ½” to
¾” for ease of placement.
Class II - Coarse sands and gravel with maximum particle size
of 1½”, including variously graded sands and gravel containing
small percentages of fines, generally granular and noncohesive, wet or dry.
110 - 130 pounds per cubic foot. Pipe sizes less
than 10” should limit maximum particle size to ½” to
¾” inch for ease of placement.
Class III - Fine sand and clay gravel, including fine sands,
sand-clay mixtures, and gravel-clay mixtures.
140 - 150 pounds per cubic foot.
Class IV - Silt, silty clays, and clays, including inorganic clays
and silts of medium to high plasticity and liquid limits.
150 - 180 pounds per cubic foot.
Class V - Includes organic soils as well as soils containing
frozen earth, debris, rocks larger than 1½” in diameter, and
other foreign materials.
Not recommended for backfill except in the final
backfill zone.
* For further classification of soils the designer may want to review ASTM D2487, "Standard Test Method for
Classification of Soil for Engineering Purposes."
Figure C-2
TRENCH COEFFICIENT, Cd
DEPENDENT ON SOIL TYPE AND DITCH CONFIGURATION
In general practice, the trench width can be kept to a minimum of six inches per side greater than the pipe diameter
itself. Although this may seem narrow in comparison to trenching of conventional materials, it must be noted that
®
PolyPipe can be pre-assembled above ground and later placed into the trench. The trench width should be
maintained as narrow as possible as the soil loading on the pipe is a relationship of the trench width.
C-3
PolyPipe 12/05
The linear deflection of the pipe can be calculated from the following modified Spangler equation 6:
Δx =
Where
Δx
Dl
K
W
E
E’
DR
=
=
=
=
=
=
=
Dl ⋅ K ⋅ W
⎛
⎞
2E
⎜⎜
⎟ + 0.061E '
3 ⎟
(
)
−
3
DR
1
⎝
⎠
(18)
Horizontal deflection or change in diameter, inches
Deflection lag factor, PolyPipe® recommends 1.0 (dimensionless)
Bedding constant, PolyPipe® recommends 0.1 (dimensionless)
Earthload, lbs/inch (See Equation (17))
Modulus of elasticity of pipe, 30,000 psi
Soil modulus, psi
Dimension ratio, (dimensionless)
* For further values of K see reference.
The percent deflection can be calculated by use of the following formula 6:
d=
Where
d
Δx
D
=
=
=
Δx
⋅100
D
(19)
Percent deflection, %
Horizontal deflection, inches (See Equation (18))
Table C-4
TYPICAL SOIL MODULUS VALUES (PSI)
Type of Soil
Depth of Cover
Standard AASHTO relative compaction
ft
m
85%
90%
95%
100%
Fine-grained soils with less than
25% sand content (CL, ML, CL-ML)
0-5
5-10
10-15
15-20
0-1.5
1.5-3.1
3.0-4.6
4.6-6.1
500
600
700
800
700
1000
1200
1300
1000
1400
1600
1800
1500
2000
2300
2600
Coarse-grained soils with fines
(SM., SC)
0-5
5-10
10-15
15-20
0-1.5
1.5-3.0
3.0-4.6
4.6-6.1
600
900
1000
1100
1000
1400
1500
1600
1200
1800
2100
2400
1900
2700
3200
3700
Coarse-grained soils with little or no
fines (SP, SW, GP, GW)
0-5
5-10
10-15
15-20
0-1.5
1.5-3.0
3.0-4.6
4.6-6.1
700
1000
1050
1100
1000
1500
1600
1700
1600
2200
2400
2500
2500
3300
3600
3800
6
Plastics Pipe Institute. Underground Installation of Polyethylene Pipe, 1996.
C-4
PolyPipe 12/05
Values of modulus of soil reaction, E' (psi) based on depth of cover, type of soil, and relative compaction. Soil type
symbols are from the United Classifications System. Source: Hartley, James D. and Duncan, James M., "E' and
its Variation with Depth," Journal of Transportation, Division of ASCE, Sept. 1987.
WALL BUCKLING
PolyPipe®, when buried in dense soil conditions and subjected to excessive external loading, will exhibit the
tendency of wall buckling. As seen in Figure C-3, wall buckling is a longitudinal wrinkle that usually occurs
between the 10:00 and 2:00 positions. Wall buckling should become a design consideration when the total vertical
load exceeds the critical buckling stress of PolyPipe®.
Figure C-3
Vertical loading can be determined by the summation of the calculated dead load (load resulting from backfill
overburden and static surface loads) and live load (loads resulting from cars, trucks, trains, etc.).
BACKFILL LOAD
1
Pb =
Where
Pb
ρsoil
H
ρ soil ⋅ H
(20)
144
= Backfill load, psi
= Backfill density, lbs/ft3
= Height of backfill above pipe, feet
SURFACE LOAD
Surface loads are those forces exerted by permanent structures in close proximity to buried PolyPipe®. These
loads can be buildings, storage tanks, or other structures of significant weight that could add to the backfill loading.
The force exerted on PolyPipe® by structural surface loads can be approximated by use of the following
Boussinesq 17 formulation:
Ps =
Where
Ps
L
z
R
=
=
=
=
3 Lz 3
144 ⋅ 2πR 5
(21)
Surface load on pipe, psi
Static surface load, lbs.
Vertical distance from top of pipe to surface load level, feet
Straight line distance from the top of pipe to surface load, feet
Where,
1
Nayyar, Mohinder L. Ed. Piping Handbook. 6th Edition. New York: McGraw-Hill, Inc., 1992.
Chen, W. F., Liew, Richard L. Y. The Civil Engineering Handbook. New York: CRC Press, 2003. 2nd Edition.
17
C-5
PolyPipe 12/05
R=
Where
x
y
z
=
=
=
(22)
x2 + y2 + z2
Horizontal distance from surface load, feet (Refer to Figure C-4)
Horizontal distance from surface load, feet (Refer to Figure C-4)
Vertical distance from top of pipe to surface load level, feet (Refer to Figure C-4)
Figure C-4
RESULTANT SURFACE LOAD
LIVE LOAD
Live loading can be determined by extracting the load from Figure C-5 for H20 highway loading or from Figure C-6
for Cooper E-80 loading or by estimating, using available analytical techniques.
Figure C-5
H20 HIGHWAY LOADING
Note: The H20 live load assumes two 16,000 lb. loads applied to two 18" x 20" areas, one located over the point in question,
and the other located at a distance of 72" away. In this manner, a truckload of 20 tons is simulated.
Source: American Iron and Steel Institute, Washington, DC
C-6
PolyPipe 12/05
Figure C-6
COOPER E-80
Note: The Cooper E-80 live load assumes 80,000 pounds applied to three 2' x 6' areas on 5' centers, such as might be
encountered through live loading from a locomotive with three 80,000 pounds axle loads.
Source: American Iron and Steel Institute, Washington, DC
TOTAL EXTERNAL LOADING
Total Load = Live Load + Backfill Load + Surface Load
Pt = Pl + Pb + Ps
(23)
Once the external loading on buried PolyPipe® has been determined, it will be necessary to calculate the critical
buckling stress for contained PolyPipe® to determine if the pipe can withstand the external loading. The external
loading capacity, or critical buckling stress, can be determined by the use of the following Von Mises formula:
Pcb =
Where
Pcb
SF
Rw
B
Es
E
DR
=
=
=
=
=
=
=
1
SF
⎛ 2.67 ⋅ Rw ⋅ B ⋅ E s ⋅ E ⎞
⋅⎜
⎟
DR 3
⎝
⎠
H ⎞
⎛
Rw = 1 − ⎜ 0.33 ⋅ w ⎟
H ⎠
⎝
=
=
(24)
Critical buckling stress, psi
Safety factor, PolyPipe® recommends SF=2
Water buoyancy factor, (dimensionless)
Empirical Coefficient of Elastic Support, (dimensionless)
Soil modulus, (See Table C-4)
Pipe modulus of elasticity, psi
Dimension Ratio
Where,
Hw
H
1/ 2
(25)
Height of water table above pipe, feet
Height of soil cover above pipe, feet
Note: Hw must be less than H
and,
C-7
PolyPipe 12/05
B=
Where
e
H
=
=
1
1 + 4 ⋅ e − 0.065⋅ H
(26)
2.718
Height of soil cover above pipe, feet
If the total external loading, Equation (23), is less than the critical buckling stress (Pt < Pcb), then the application
should be considered safe. However, if this is not the case (Pt > Pcb), then the required parameters can be
determined for a safe application from the following variations of the above equation:
or
⎛ 2.67 ⋅ Rw ⋅ B ⋅ E s ⋅ E ⎞
⎟
DR = ⎜⎜
2
⎟
SF 2 ⋅ Pcb
⎠
⎝
P ⋅ SF 2 ⋅ DR 3
E s = cb
2 .67 ⋅ R w ⋅ B ⋅ E
(27)
2
(28)
NOTICE:
®
should be independently verified. In all cases, the user should assume that additional safety measures might be required in
the safe installation or operation of the project. Due to the wide variation in service conditions, quality of installation, etc., no
C-8
PolyPipe 12/05
EFFECTS OF TEMPERATURE
THERMAL CONDUCTIVITY
The thermal conductivity of a material is expressed as the rate at which heat is transferred by conduction through a
unit cross-sectional area of a material when a temperature gradient exists perpendicular to the area. The units
generally used for expressing this value are BTU - in per hour, per square foot, per °F.
PolyPipe®, like many thermoplastic materials, has a low coefficient of thermal conductivity. PolyPipe® has an "R"
value of 0.3 BTU/in. Table D-1 below shows the value of PolyPipe® compared to the value of some conventional
materials.
Table D-1
THERMAL CONDUCTIVITY OF MATERIALS
Material
BTU - in/ft2/hr/°F
Copper
Aluminum
Steel
Cast Iron
Glass
PolyPipe®
Urethane
3027
1457
411
302
7.2
2.7
0.6
Due to its low value of thermal conductivity, PolyPipe® is a fairly good insulator.
THERMAL EXPANSION AND CONTRACTION
As with all materials, PolyPipe® is subject to expansion/contraction due to changes in temperatures. It is important
to consider this property when designing a piping system. The coefficient of thermal expansion/contraction, α, for
PolyPipe® is approximately:
1.0 x 10-4 inch per inch per oF (1.75 • 10-4 mm/mm/°C)
The amount of expansion/contraction can be calculated by the following formula 11:
Δl = l ⋅ α ⋅ (T2 − T1 )
Where
Δl
α
l
T1
T2
=
=
=
=
=
(29)
Change in length, inches
Coefficient of thermal expansion, 1.0 x 10-4 in/in/°F
Initial pipe length, inches
Initial temperature, °F
Final temperature, °F
*NOTE: The calculated expansions in a line do not often occur unless the pipe is free of all frictional drag.
EXAMPLE: A 500 ft. long (152 m) unrestrained pipe run is subjected to a temperature fluctuation from 90oF (32oC)
during the day to 65oF (18oC) at night. Calculate the change in length due to the temperature difference from day
to night.
Δl = (1.0 x10 −4 )(90 − 65)(500)(12) = 15 inches (1.25 feet)
11
Plastics Pipe Institute Technical Report-21. Thermal Expansion and Contraction in Plastics Piping Systems, 2001.
D-1
PolyPipe 12/05
Temperature gradients produced through a change in fluid or ambient temperature will create a gradient across the
pipe wall. The midwall temperature of the pipe will reflect neither the internal nor the external condition. The effect
of the temperature gradient occurs more gradually due to the low thermal conductivity of PolyPipe®. Polyethylene,
which is viscoelastic, undergoes a molecular rearrangement due to the temperature gradient. This restructure
dissipates a large portion of the temperature-induced stresses. This behavior is referred to as stress relaxation and
is considered beneficial to a pipe system that may experience temperature fluctuations. In certain circumstances, it
is necessary to be able to calculate the degree of stress imparted to the pipe due to an environmental or process
change.
In a system where the pipe is restrained at both ends, a compressive stress is created. Thermally induced forces
for polyethylene can be calculated from the following equation 11:
and,
Where
F
σ
A
E
ΔT
α
=
=
=
=
=
=
F =σ ⋅ A
(30)
σ = E ⋅ α ⋅ ΔT
(31)
Force, lbs
Stress, psi
Pipe wall cross-sectional area, in2
Modulus of elasticity, psi
Temperature change, °F
The modulus of elasticity, E, for polyethylene is a function of time and temperature.
Please refer to the Plastics Pipe Institute (PPI) Engineering Handbook chapter on Engineering Properties for more
information.
A buried system, by virtue of the continuous contact of the backfill material and the reduction in temperature
fluctuations, needs no further special considerations. Pipe to soil friction will restrain the buried pipe in place.
Above ground pipeline, however, does not have restraints and the thermal expansion/contraction must be allowed
for in the design. The design must incorporate necessary restraints to accommodate adverse effects due to
thermal expansion/contraction. This may be accomplished by one of the following methods:
1. The pipeline design contains no restraints allowing the pipeline to move freely.
2. Anchored closely and tightly so that unit changes occur in the elasticity of the material rather than transferring
all the forces to one point.
3. Anchoring ends and changes in direction with addition of expansion loops at or near the mid-point of a run.
For long continuous pipelines laid above ground, the amount of expansion/contraction can be significant as a result
of normal variances in temperature from day to night. The pipeline should be installed to minimize direct sunlight.
As the pipe temperature increases, the movement is generally from side to side. Although this expansion cannot
(1)
be prevented, placing anchor points at intervals along the line can control it. The formula shown below is used to
estimate the distance between the anchor points.
11
D-2
PolyPipe 12/05
L=
Where
L
Δy
α
ΔT
=
=
=
=
2 ⋅ Δy 2
α ⋅ ΔT
(32)
Distance between anchor points, inches
Lateral deflection, inches
Temperature change, °F
Recommendations regarding the installation of the pipe expected to undergo temperature fluctuations are given in
Section F.
NOTICE:
®
D-3
PolyPipe 12/05
CHEMICAL RESISTANCE15
Thermoplastic materials generally are resistant to attack from many chemicals, which make them suitable for use in
many process applications. The suitability for use in a particular process piping application is a function of:
1. Material
A. The specific plastic material: ABS, CPVC, PP, PVC, PE, PB, PVDF, PEX, PA11, PK.
B. The specific plastic material and its physical properties as identified by its cell classification according to
the appropriate ASTM material specification.
2. Product and Joint System
A. Piping product dimensions, construction, and composition (layers, fillers, etc.).
B. Joining system. Heat fusion and solvent cementing do not introduce different materials into the system.
Mechanical joints can introduce gaskets such as elastomers, or other thermoplastic or non-thermoplastic
materials used as mechanical fitting components.
C. Other components and appurtenances in the piping system.
3. Use Conditions - Internal and External
A. Chemical or mixtures of chemicals, and their concentrations.
B. Operating temperature — maximum, minimum, and cyclical variations.
C. Operating pressure or applied stress — maximum, minimum and cyclical variations.
D. Life-cycle information — such as material cost, installation cost, desired service life, maintenance, repair
and replacement costs, etc.
Polyethylene does not rust, rot, pit or corrode as a result of chemical, electrolytic or galvanic action. Chemicals that
pose potentially serious problems for polyethylene are strong oxidizing agents or certain hydrocarbons. These
chemicals may reduce the pressure rating for the pipe or be unsuitable for transport. Either can be a function of
service temperature or chemical concentration.
Continuous exposure to hydrocarbons can lead to permeation through the material or elastomeric gaskets used at
joints. The degree of permeation is a function of pressure, temperature, the nature of the hydrocarbons and the
polymer structure of the piping material. The chemical environment may also be of concern where the purity of the
fluid within the pipe must be maintained. Hydrocarbon permeation may affect pressure ratings and hinder future
connections.
For more detailed information on chemical resistance, The Plastics Pipe Institute (PPI) has prepared a technical
report, TR-19 “Thermoplastic Piping for the Transport of Chemicals”, as a service to the industry. This document is
available via download from the PPI website www.plasticpipe.org.
NOTICE:
®
15
Plastics Pipe Institute Technical Report-19. Thermoplastic Piping for the Transport of Chemicals. 2000.
E-1
PolyPipe 12/05
UNDERGROUND INSTALLATIONS
The installation of pipes constructed from conventional materials generally requires the joining and laying of the
pipe piece by piece in the trench. This will necessitate the trench being of such width it will accommodate one or
two installers carrying out the installation with their tools and enough room for them to work.
Due to the flexibility and resilience of PolyPipe®, it can be pre-assembled above ground. This not only allows for
ample working area, but also provides an opportunity for a thorough inspection of butt-fused joints prior to burial.
The trench dimensions are very narrow in comparison to widths used for traditional materials and can be
constructed by any one of a number of types of machinery.
As with any operation, a large contribution to the success of the job can be made by adequate planning. In many
instances it may not be possible to avoid some difficult circumstances that may result in extended installation time.
This is particularly true for installation of steel pipe. As an example, in very uneven or hilly terrain, the lightweight of
PolyPipe® would be a definite advantage allowing the pipe to be assembled in a more suitable area and then
carried or pulled to the job site in longer sections for installation into the trench.
TRENCHING
As has been previously stated, the trench width should be as narrow as possible. The maximum width should be
no more than the diameter of the pipe plus two feet. If possible, the trench can be made as narrow as the pipe
itself plus one foot. The importance of the trench width is not so much the cost of the trenching, which is of course
is a factor, but more the working efficiency of the finished system. Trenches should be as straight-sided as is
practical and flat-bottomed to facilitate the proper consolidation and packing of the filling materials (See Figure F-2).
In ground that is coarse grain with many large rocks or protrusions, it may be necessary to over-cut and lay a bed
of fine gravel in the base of the trench to allow for stress-free bedding of the pipe. It is not recommended that
ordinary sand be used for this purpose, as it is possible to be washed away, leaving the pipe unsupported.
The formation of the base of the trench is of great importance. It should be as flat and level as possible or graded
to the correct slope where specified. An installation where this is significant would be a gravity flow system.
Grading can be accomplished by the use of gravel or finely crushed stone. If the condition of the soil is poor due to
standing water in a high water table area, it may be required to establish more stabilization to the base of the trench
after having drained the area first. In rocky terrain, the installation should be made such that the pipe is not laid in
direct contact with the hard surface. The trench should be cut to a depth of six inches to one foot below the
required level and then brought back to grade with soil or fine gravel. Ditches in soil that is loose may require a
slope to the top edges of the trench to prevent the collapsing of the sides and filling of the trench (See Figure F1(b)). In some cases it may be preferable to excavate a trench having a wider top section cut straight down to the
intended top position of the pipe. This trench configuration is represented in Figure F-1(c). In either case, the
backfilling of the trench will not result in higher earth load on the pipe.
Figure F-1
DITCH CONFIGURATIONS
(a) (b)
(c)
F-1
PolyPipe 12/05
PIPE CURVATURE
In the building of long runs of pipe it is often necessary to negotiate bends. The natural flexibility of polyethylene
will allow runs of pipe to be pulled around fairly tight radii. Trenches can therefore be excavated to accommodate
bends, which are within the capabilities of the pipe.
The degree to which a pipe can be cold bent around a radius is dependent upon the diameter to wall thickness
ratio, D/t, or the DR ratio. The table below lists minimum recommended bending radius for any size of pipe.
Table F-1
MINIMUM BENDING RADIUS
DR Ratio
Minimum Radius Factor, Kmrf
32.5
26
21
17
15.5
11 or lower
40
36
32
26
24
20
By multiplying the minimum radius factor, Kmrf, by the actual outside diameter, D, of the pipe being installed you can
determine the minimum bending radius, rm, for the pipe being installed. Use the following formula:
rm = D ⋅ K mrf
(33)
Example: 8” IPS SDR 32.5 pipe would have a minimum bending radius of (8.625”)(40) = 345” or 28.74’
A system that requires a bend and can be done so by utilizing the natural curvature of the pipe does not require the
use of thrust blocks. However, tight bends in polyethylene should be buried or constrained. Where there is a need
for the placement of a compression fitting, it may also be necessary to use an anchor or a thrust block. Fused or
flanged joints generally do not require thrust blocking. Thrust blocks should be constructed of a poured reinforced
concrete pad that partially encapsulates the fitting and prevents any relative movement between the straight
section or "run" of the fitting and the branch. Thrust blocks must be poured on undisturbed soil or the soil must be
compacted.
In most cases, well compacted soil placed strategically against the heel of an elbow or the back of a tee is sufficient
for thrust blocking. This precaution should be taken to prevent any unnecessary stressing of the pipe and to
ensure that the expansion and contraction of the pipe is forced to take place in the direction it is designed to go.
PIPE LAYING
If the pipe is to be joined piece by piece at the trench site prior to being lowered into the trench, the transport of the
pipe lengths to the work site is of little consideration. In those situations where on-site conditions require that
several lengths be butt fused in a remote position from the trench, then there are some other considerations to be
taken into account. The effect of pulling a number of joined lengths of pipe across the ground by gripping one end
results in the generation of a tensile load in the pipe.
The size of pipe will determine the means used to lay the pipe in the trench. For sizes up to 6” (152mm) the pipe
can be manhandled fairly readily and laid in the desired position. Single joints of up to 10” (254mm) in diameter
can also be laid in the trench manually if they are to be butt fused afterwards. Sizes above 10” (254mm) will
require moving and positioning with the use of equipment such as pry bars or perhaps light construction equipment.
Larger diameters will need to be placed into the trench with rubber-tired lifting equipment or lifted into position with
a cherry picker.
In the pipe-laying phase, some accommodations can be made to allow for thermal expansion/contraction.
Placement of the pipe in the trench will normally provide for some “snaking”. Even straight lengths have a
tendency to wave from side to side. Pipe should not be pulled to straighten. Leave the side-to-side path and cut to
length for the tie-in. Whenever possible, a final tie-in should be performed after an overnight stay in the trench to
allow the pipe to cool down to near normal soil conditions.
F-2
PolyPipe 12/05
Connections made to valves, rigid pipes or manholes should be supported. An alternative for some of these
situations is the construction of a solidified, well tamped bedding below the joint. A concrete pad should be
installed under the heavy member to resist settlement and preclude the polyethylene pipe supporting the
component. The need for support of this kind is especially critical in unstable soil conditions.
PULLING LENGTHS
The following information may be used to estimate an allowable pulling length for nominal polyethylene pipe
applications. The equations shown below result in a pulling length that is based on short-term tensile strength.
Use of pull forces greater than calculated may result in pipe damage. PolyPipe® recommends a load cell be used
to monitor the applied force. This information is also available in PolyPipe® Info Brief #6.
The Maximum Pulling Force (MPF) in pounds that may be applied to the pipe can be calculated by the following
equation 14:
1 ⎞
⎛ 1
−
MPF = f y ⋅ f t ⋅ T ⋅ π ⋅ D 2 ⋅ ⎜
2 ⎟
⎝ DR DR ⎠
Where
MPF
fy
ft
=
=
=
T
D
DR
=
=
=
(34)
Maximum pulling force, lbs (ATL and MPF are synonymous)
Tensile yield design (safety) factor, 0.40
Time under tension design (safety) factor, 0.95*
*The value of 0.95 is adequate for pulls up to 12 hours.
Tensile yield strength, psi (See Table F-2 below)
Outside diameter of pipe, inches
Dimension ratio (dimensionless)
Table F-2
TENSILE YIELD STRENGTHS
Tensile Yield Strength, psi
Temperature, oF
PE3408
PE2406
73
100
120
140
3,500 psi
2,800 psi
2,300 psi
1,800 psi
3,000 psi
2,400 psi
2,000 psi
1,600 psi
Once the Maximum Pulling Force is determined, one can calculate the maximum pulling length, MPL, of the HDPE
material for the type of installation. Installations can be divided into four categories:
1.
2.
3.
4.
On level soil.
Through an existing conduit that is empty.
Through an existing conduit where the HDPE and the existing conduit are both full of water.
Through a bored hole using the horizontal drilling technique.
1. LEVEL SOIL 12:
Where
MPL
MPF
f
W
=
=
=
=
MPL =
MPF
f ⋅W
(35)
Maximum pulling length, feet
Maximum pulling force, lbs (Equation (34))
Coefficient of friction on smooth sandy soil, 0.7 (dimensionless)
Weight of pipe, lbs/ft
14
ASTM F1804-03. Standard Practice for Determining Allowable Tensile Load for Polyethylene (PE) Gas Pipe During Pull-In Installation. Volume 8.04.
American Society of Testing and Materials. Baltimore, 2004.
12
F-3
Plastics Pipe Institute. Pipeline Rehabilitation by Sliplining with Polyethylene Pipe, 1993.
PolyPipe 12/05
2. SLIPLINING EMPTY:
For determining the Maximum Pulling Length of HDPE pipe through an existing conduit that is straight, level, and
empty, PolyPipe® recommends using the same procedure for determining the pulling length on a relatively flat
surface aboveground.
3. SLIPLINING WET:
For slip lining conduits where the HDPE pipe and existing conduit are both full of water, the maximum allowable
pulling length can be estimated by using a coefficient of friction of 0.1.
4. BORED HOLES:
Estimating the maximum pulling length for holes as provided by the horizontal directional drilling (HDD) technique is
more complex. Two references are available to assist in the design of HDD applications: Plastics Pipe Institute
(PPI) Engineering Handbook, “Polyethylene Pipe for Horizontal Directional Drilling” available at their website,
www.plasticpipe.org; and, ASTM F1962, “Standard Guide for Use of Maxi-Horizontal Directional Drilling for
Placement of Polyethylene Pipe or Conduit Under Obstacles, Including River Crossings”. If further assistance is
needed, please contact PolyPipe® Technical Services Department at (800) 433-5632.
Before the pipe is pulled into position, a survey of the area should be made to ensure that surface conditions will
not cause the pipe to suffer any damage in the form of gouges or deep scarring. A system of rollers constructed
from short lengths of pipe can be used to reduce the pulling force required and to keep the pipe off the ground.
A pulling head is used to attach to the leading end of the pipe. This can take the form of a simple rubber pad with
steel cable wrapped around the pipe or can be more sophisticated in the form of a pulling head. The pipe should
never be pulled by attaching to the flange. If flange assemblies are installed, these must be elevated to avoid
dragging, both in front and behind.
BACKFILLING
Not only is backfill utilized to fill the trench, but it also serves a very specific design function. The main purpose of
the backfill material is to provide adequate support and protection for the pipe. By ensuring the backfill is solid and
continuous, damage can be prevented from surface traffic, falling rock or lifting due to the trench filling with water.
The soil used for backfill can be the original soil excavated from the trench or foreign soil that has been transported
to the site. Whatever soil is used, it is recommended that the haunching and the initial backfill material be free of
any rocks, hard lumps, frozen material or clay. It should also be sufficiently friable to readily flow into the haunches
of the pipe. It is important that the initial backfill be consolidated to ensure continuous contact and support of the
pipe (See Figure F-2). This can be achieved by using fill material that is of fine sand or clay based materials.
These materials should only be used in dry areas where it is unlikely to be washed out.
Figure F-2
PROPER BACKFILL
Improper Backfill
Proper Backfill
F-4
PolyPipe 12/05
TRENCH CONFIGURATION AND TERMINOLOGY
The figure below describes a typical, well-constructed trench arrangement and gives the correct descriptive
terminology for the various components.
Figure F-3
TRENCH CONFIGURATION
Foundation and Bedding - Use of foundation material may only be required where the base of the trench is
required to be brought up to the pipeline level, or when encountering an unstable or rocky trench bottom. As noted
earlier, this can be soil or fine gravel.
Haunching - The haunching provides stability to the pipe from the sides and from underneath. The best material is
crushed stone, fine gravel or coarse sand, and should be tampered into position with a narrow tamping tool to
ensure that the material is well consolidated under the sides of the pipe as well as around it. The haunching
material must be poured into the trench gradually so that the tamping operation can be carried out simultaneously
with the placement. Applying too much of the material at one time may cause a bridging effect which will result in a
cavity being formed below the pipe, which can later result in a loss of support for the pipe.
Figure F-4
PROPER HAUNCHING
Correct Haunching
Incorrect Haunching
Initial Backfill – Materials include coarse sand, fine gravel or crushed stone. This section of the backfilling should
be carried out the same as with the haunching. The material should be gradually added in 4-6 inch (102-152 mm)
lifts and tamped simultaneously. The initial backfill should be brought up to a height of 6-12 inches (152-305 mm)
above the top of the pipe, depending upon the size of the pipe.
F-5
PolyPipe 12/05
Final Backfill - As previously mentioned, the final backfill can be the original excavated material or other
convenient soil, provided it does not contain excessively large rocks or frozen lumps that may damage the pipe
initially or later allow washing away and the loss of consolidation. The backfill should be compacted per the
requirements addressed in Chapter E.
In areas where a high water table exists, it is necessary to allow for the effect of buoyancy of the pipe and of the
backfill material. The result of the fill material being saturated due to the water table will reduce the load imparted
on the pipe. In these conditions, the conventional trench configuration will no longer be sufficient to overcome a
tendency for the pipe to float.
This situation can be addressed by designing for a certain amount of extra cover to ensure the pipe will remain in
place. The required depth of cover can be calculated from the equation below:
ρ w ⋅ π ⋅ (D 2 − d 2 ) − W p
H =
48 ⋅ ρ s ⋅ D
Where
H
ρw
Wp
ρs
D
d
=
=
=
=
=
=
(36)
Minimum backfill depth, feet
Density of water, lbs/ft3
Density of soil, lbs/ft3
RECOMMENDED TESTING PROCEDURE
LEAK TESTING
The intent of leak testing is to find unacceptable faults in a piping system. If such faults exist, they may manifest
themselves by leakage or rupture.
Leakage tests may be performed if required in the Contract Specifications. Testing may be conducted in various
ways. Internal pressure testing involves filling the test section with a nonflammable liquid or gas, then pressurizing
the medium. Hydrostatic pressure testing with water is the preferred and recommended method. Other test
procedures may involve paired internal or end plugs to pressure test individual joints or sections, or an initial
service test. Joints may be exposed to allow inspection for leakage.
Liquids such as water are preferred as the test medium because less energy is released if the test section fails
catastrophically. During a pressure test, energy (internal pressure) is applied to stress the test section. If the test
medium is a compressible gas, then the gas is compressed and absorbs energy while applying stress to the
pipeline. If a catastrophic failure occurs, both the pipeline stress energy and the gas compression energy are
suddenly released. However, with an incompressible liquid such as water as the test medium, the energy release
is only the energy required to stress the pipeline.
WARNING: Pipe system pressure testing is performed to discover unacceptable faults in a piping system.
Pressure testing may cause such faults to fail by leaking or rupturing. This may result in catastrophic
failure. Piping system rupture may result in sudden, forcible, uncontrolled movement of system piping or
components, or parts of components.
WARNING: Pipe Restraint. The pipe system under test and any closures in the test section should be
restrained against sudden uncontrolled movement from catastrophic failure. Test equipment should be
examined before pressure is applied to insure that it is tightly connected. All low pressure filling lines and
other items not subject to the test pressure should be disconnected or isolated.
WARNING: Personal Protection. Take suitable precautions to eliminate hazards to personnel near lines
being tested. Keep personnel a safe distance away from the test section during testing.
F-6
PolyPipe 12/05
Pressure Testing Precautions
The piping section under test and any closures in the test section should be restrained or otherwise restricted
against sudden uncontrolled movement in the event of rupture. Expansion joints and expansion compensators
should be temporarily restrained, isolated or removed during the pressure test.
Testing may be conducted on the system, or in sections. The limiting test section size is determined by test
equipment capability. If the pressurizing equipment is too small, it may not be possible to complete the test within
allowable testing time limits. If so, higher capacity test equipment, or a smaller test section may be necessary.
If possible, test medium and test section temperatures should be less than 100oF (38oC). At temperatures above
100oF (38oC), reduced test pressure is required. Before applying test pressure, time may be required for the test
medium and the test section to temperature equalize. Contact the pipe manufacturer for technical assistance with
elevated temperature pressure testing.
Test Pressure
Valves, or other devices may limit test pressure, or lower pressure rated components. Such components may not
be able to withstand the required test pressure, and should be either removed from, or isolated from the section
being tested to avoid possible damage to, or failure of these devices. Isolated equipment should be vented.
For continuous pressure systems where test pressure limiting components or devices have been isolated, or
removed, or are not present in the test section, the maximum allowable test pressure is 1.5 times the system
design pressure at the lowest elevation in the section under test.
If the test pressure limiting device or component cannot be removed or isolated, then the limiting section or
system test pressure is the maximum allowable test pressure for that device or component.
For non-pressure, low pressure, or gravity flow systems, consult the piping manufacturer for the maximum
allowable test pressure.
Test Duration
For any test pressure from 1.0 to 1.5 times the system design pressure, the total test time including initial
pressurization, initial expansion, and time at test pressure, must not exceed eight (8) hours. If the pressure test is
not completed due to leakage, equipment failure, etc., the test section should be de-pressurized, and allowed to
"relax" for at least eight (8) hours before bringing the test section up to test pressure again.
Pre-Test Inspection
Test equipment and the pipeline should be examined before pressure is applied to ensure that connections are
tight, necessary restraints are in-place and secure, and components that should be isolated or disconnected are
isolated or disconnected. All low pressure filling lines and other items not subject to the test pressure should be
disconnected or isolated.
Hydrostatic testing
Hydrostatic pressure testing is preferred and is strongly recommended. The preferred testing medium is clean
water. The test section should be completely filled with the test medium, taking care to bleed off any trapped air.
Venting at high points may be required to purge air pockets while the test section is filling. Venting may be
provided by loosening flanges, or by using equipment vents. Re-tighten any loosened flanges before applying test
pressure.
Monitored Make-up Water Test
The test procedure consists of initial expansion, and test phases. During the initial expansion phase, the test
section is pressurized to the test pressure, and sufficient make-up water is added each hour for three (3) hours to
return to test pressure.
After the initial expansion phase, about four (4) hours after pressurization, the test phase begins. The test phase
may be one (1), two (2), or three (3) hours, after which a measured amount of make-up water is added to return to
test pressure. If the amount of make-up water added does not exceed Table F-3 values, leakage is not indicated.
F-7
PolyPipe 12/05
Table F-3
TEST PHASE MAKE-UP AMOUNT
Nominal Pipe Size
inches
2
3
4
5
6
8
10
12
14
16
18
U.S. Gals/100 ft of Pipe
1-Hour
2-Hour
3-Hour
0.07
0.11
0.19
0.10
0.15
0.25
0.13
0.25
0.40
0.19
0.38
0.58
0.30
0.60
0.90
0.50
1.00
1.50
0.80
1.30
2.10
1.10
2.30
3.40
1.40
2.80
4.20
1.70
3.30
5.00
2.00
4.30
6.50
Nominal Pipe Size
inches
20
22
24
28
30
32
36
42
48
54
--
U.S. Gals/100 ft of Pipe
1-Hour
2-Hour
3-Hour
2.80
5.50
8.00
3.50
7.00
10.50
4.50
8.90
13.30
5.50
11.10
16.80
6.30
12.70
19.20
7.00
14.30
21.50
9.00
18.00
27.00
12.00
23.10
35.30
15.00
27.00
43.00
18.50
31.40
51.70
----
Non-monitored Make-Up Water Test
The test procedure consists of initial expansion, and test phases. For the initial expansion phase, make-up water is
added as required to maintain the test pressure for four (4) hours. For the test phase, the test pressure is reduced
by 10 psi. If the pressure remains steady (within 5% of the target value) for an hour, no leakage is indicated.
The above testing procedures were taken from the Plastic Pipe Institute Engineering Handbook; Inspections, Tests
and Safety Concerns.
Pneumatic Testing for Gravity Sewers
For gravity sewer lines, low-pressure air may be used as per ASTM F1417. However, any other pneumatic testing
is not recommended. Additional safety precautions may be required.
The piping manufacturer should be consulted before using pressure-testing procedures other than those presented
here. Other pressure testing procedures may or may not be applicable depending upon piping products and/or
piping applications.
NOTICE:
®
should be independently verified. In all cases, the user should assume that additional safety measures may be required in the
F-8
PolyPipe 12/05
MARINE APPLICATIONS
PolyPipe® is ideally suited for use in marine application, whether it be oceans, lakes, ponds, swamps, or rivers.
The crossing of a fluidized area with a polyethylene pipeline has some similarities and some differences to normal
on-shore installations. Recognizing and treating these design and operating parameters is important.
Polyethylene pipe, due to its cross-sectional density, will float near or on the liquid surface. Transporting a liquid
comparable to the external liquid allows the polyethylene to float with the crown of the pipe just breaking the
surface.
The inherent qualities of PolyPipe® (flexibility, light weight, corrosion resistance, homogeneous lengths and
abrasion resistance) allow its’ acceptance in dredging, aeration ponds, outfall and intake lines. Factors to be
considered in the installation of marine pipelines include the following:
Flotation or sinking
Internal pressure capabilities
Collapse resistance of pipe
Weighting
FLOTATION OR SINKING
A polyethylene pipeline with comparable densities of liquid inside and outside will float in equilibrium at the surface.
An increase in weight of 10-20% of pipe weight will sink the pipe to the bottom, provided no underwater currents
exist. A line from a dredge or across a settling pond will float while pumping only water. If solids are introduced or
the density of the fluid is higher than the surrounding fluid, the pipeline will sink. This operational technique may be
acceptable in this instance and require neither anchors nor flotation devices. If the pipeline is to be moved, the line
should be flushed until flotation occurs.
Where flotation of the line is desired or to maintain the profile at or near the surface, various forms of collars,
saddles, and strap-on devices are available. These can be continuous supports or placed at intervals
approximately double that required for weights. Parallel-capped polyethylene pipelines can also be utilized as
flotation devices. Size and spacing of flotation collars is based on desired position of the carrier pipe relative to the
water surface and weight of the pipeline.
For underwater installations, it is important to select the proper weight and spacing of the weight. Whenever
possible, an underwater pipeline should be installed in a trench.
INTERNAL PRESSURE
A marine pipeline, like any other, should be designed to withstand the anticipated pressure and pressure surges.
In some cases, other design parameters require a heavier wall than does the working pressure. In these cases,
offshore design should prevail on the marine portion and conventional design should prevail for the on-shore
portion.
COLLAPSE RESISTANCE
The piping application and installation procedure can require a heavier wall pipe than pressure carrying capabilities
alone. Resistance to collapse of the pipe due to bending, external loading or environmental forces must be
addressed. See Table A-7 for external load capabilities of PolyPipe® and Section C for method of calculating
collapse pressures. The pipe, being submerged, is subjected to external pressures from the surrounding fluid.
This pressure may have the effect of causing a collapse if the pipe should be only partially full, or, in the worst
case, totally empty. If the pipe is full and open-ended, the pressure on the inside will normally equal or exceed the
pressure on the outside, depending upon the pumping, and a collapse situation is not a consideration.
G-1
PolyPipe 12/05
INSTALLATION
Except in rare instances, where very long lengths of polyethylene pipe are required, the pipe can be joined by
thermal fusion and have the proper sized weights installed on-shore. These individual lengths may then be towed
into place, joined by flanged joints or by thermal fusion, and sunk in a predetermined course.
Once a pipeline has been installed in a body of water, changes in liquid flow around the pipe create different paths.
A pipeline installed on the bottom will have flows that may wash material from beneath the pipeline, creating more
upward lift than lying on the bottom. This will build sediment banks on the upstream side and eddy pools on the
downstream side that the weighted pipe may settle into.
It is worthy of note that currents as high as eight feet per second, or even higher in rivers and streams are possible.
If these conditions apply to the installed pipeline, additional design considerations should be given for additional
weight, spacing of weights and heavier wall pipe. Burial of marine pipelines, while not always possible, should not
be considered as a solution where current velocities exceed two feet per second. Present burial techniques
employ natural sedimentation processes. At some stage of the sediment accumulation, there is likely to be a
period in which the sediment is sufficiently fluidized to exert significantly higher buoyant forces than water alone.
CONTROLLED SINKING OF POLYPIPE
A polyethylene pipeline, with weights attached, ends capped and filled with air at atmospheric pressure may be
gradually sunk into position by allowing the entrance of water on a controlled basis. Filling should begin at a point
of joining to a fixed structure and proceed away. It is important to maintain progressive filling so as to lessen the
chance of an air pocket and a hump in the line filled with air. It is equally important to maintain a higher elevation
with the air-bleeding end of the pipeline so as to preclude water entering and filling from each end. When an air
pocket is captured in the middle of a line, introducing a squeegee at the fixed end and forcing it outward with water
under pressure can displace it.
WEIGHTING
PolyPipe® may be weighted and held in place by several methods. Concrete weights are the most common.
These may be either strap-on or set-on type weights. It is also possible to use screw anchors with saddles to hold
the pipe down. In some instances it may be best to install underwater pilings with crossbars to strap the pipe and
hold it in suspension between the surface and the bottom.
A pipeline used for transporting a gaseous medium or one that may have periods of gaseous pockets will have to
be weighted heavily to maintain its position on the bottom. Pipelines transporting liquids can be weighted
significantly lighter. Open-ended pipelines, such as outfall or intake pipelines, that have little chance of trapping air
in pockets to float the line, may be weighted only 10-15% over equilibrium, provided no environmental forces are
exerted on the line.
All forms of weighting devices used in restraining polyethylene pipelines should be padded from the pipe with a
resilient, impermeable padding to protect the pipe from sharp projections of concrete or metal clamps. Neoprene
sheeting or other similar compressible material from 1/8” (up to 12” nominal pipe) to 1/4” (>12” nominal pipe) in
thickness is recommended. Under set-on weights, the padding should be strapped to the pipe with stainless steel
banding.
Concrete weights should be poured from 140-160 lbs per cubic foot concrete. Both strap-on and set-on weights
should be reinforced with steel rebar. Concrete weights for 4 inch and smaller pipe may be reinforced with wire
mesh. Bolts, nuts, and other hardware used on underwater pipelines should be of corrosion resistance material
suitable to the particular location.
G-2
PolyPipe 12/05
Anchor Weight Design
The weight required to sink a pipeline is a function of the liquid volume displaced by the body (pipe), the weight of
the submerged bodies including the pipe, pipe contents, weights and the environmental conditions.
To determine the weight of the anchor in the surrounding fluid (or submerged weight), use the following formula:
Ws = W p +
π
Wt. of fluid in pipe
[(ρ
144 ⋅ 4
f
) (
⋅ d 2 − ρ s ⋅ OD 2 ⋅ K
)]
(37)
Buoyancy of pipe
Where
Ws
Wp
ρs
ρf
OD
d
K
=
=
=
=
=
=
=
Weight of anchor in surrounding fluid, lbs/ft
Density of surrounding fluid, lbs/ft3 (water, 62.4 lbs/ft3)
Density of fluid inside pipe, lbs/ft3 (water, 62.4 lbs/ft3)
Anchor constant (Refer to Table G-1)
*Note: Reference Table A-2 thru Table A-4 for pipe weights and dimensions.
The value of K, the anchor constant, should vary with the wave, tide or current conditions that are known or that are
anticipated in the pipeline crossing area. K should have a value greater than 1.0, unless neutral buoyancy is
desired.
Table G-1
ANCHOR CONSTANT VALUES
Environmental Condition
K, Anchor Constant
1.0
Neutral Buoyancy
1.3
Ponds, lakes, slow moving streams or rivers, low
currents or tidal actions
1.5
Significant stream or rover currents or tidal flows
A positive (+) force (↓) indicates the pipeline will sink without additional weighting, provided no extraneous lifting
forces are imposed on the pipeline. However, a (-) resultant force (↑) indicates additional weight is required to sink
the pipeline.
Once the proper material has been chosen for the anchor weight, the required weight can be determined from the
following equation:
Wd =
Where
Wd
S
ρa
=
=
=
S ⋅ Ws ⋅ ρ a
ρ a − (K ⋅ ρ s )
(38)
Weight of anchor on dry land, lbs
Anchor weight spacing, ft
Density of anchor weight material, lbs/ft3
The length between anchor weights, S, can vary with pipe size. A nominal 2-inch or smaller pipe should be
weighted with a ribbon weight, weights or anchors at 6–8 foot intervals. Pipe sizes 3-12 inch should have weights
every 8-12 feet and anything larger at 12-15 foot intervals.
G-3
PolyPipe 12/05
A pipeline with weights attached on dry land should be handled carefully so as not to buckle the pipe. The can be
accomplished by ramping the banks to the water’s edge and sliding the pipe on the ground after the weights have
been installed. If installing from a lay barge in the water, the weighted pipe should be supported with a stringer
from the barge.
Design and Construction of Ballast Weights 16
To prevent damage to ballasts when handling, tightening and moving PE pipe, they are typically made of suitably
reinforced concrete. Ballasts can be made to different shapes, although a symmetrical design such as round,
square or hexagonal is preferred to avoid twisting during submersion. Flat-bottomed ballasts are preferred if the
submerged piping is likely to be subjected to significant currents, tides or wave forces because they help prevent
torsional movement of the pipe.
Also, when such conditions are likely to occur the ballasts should place the pipeline at a distance of at least onequarter of the pipe diameter above the sea or riverbed. The lifting force caused by rapid water movement that is at
a right angle to a pipe that rests on, or is close to a sea or riverbed is significantly greater than that which acts on a
pipe that is placed at a greater distance from the bed. This means that ballasts designed to give an open space
between the pipe and the bed will give rise to smaller lifting forces.
The ballasts should be comprised of a top and bottom section that when mated together with a minimum gap
between the two halves provides for a resultant inside diameter that is slightly larger than the outside diameter of
the pipe. This slightly larger inside diameter is to allow the placement of a cushioning interlining to protect the softer
plastic pipe from being damaged by the hard ballast material. Another function of the interlining is to provide
frictional resistance that will help prevent the ballasts from sliding along the pipe during the submersion process.
Accordingly, slippery interlining material such as polyethylene film or sheeting should not be used. Some
suggested interlining materials include several wraps of approximately 1/8-inch thick rubber sheet or approximately
¼-inch thick neoprene sponge sheet.
Additionally, experience has shown that in certain marine applications where tidal or current activity may be
significant, it is feasible for the pipe to “roll” or “twist”. This influence combined with the mass of the individual
ballasts may lead to a substantial torsional influence on the pipe. For these types of installations, an asymmetric
ballast design in which the bottom portion of the ballast is heavier than the upper portion of the ballast is
recommended. For additional information on the design of this type of ballast, refer to Appendix A-3 of the PPI
Engineering Handbook Chapter on Marine Applications.
Suitable lifting lugs should be included in the top and bottom sections of the ballasts. The lugs and the tightening
hardware should be corrosion resistant. Stainless steel strapping or corrosion resistant bolting is most commonly
used. Bolting is preferable for pipes larger than 8-inch in diameter because it allows for post-tightening prior to
submersion to offset any loosening of the gripping force that may result from stress-relaxation of the pipe material.
Concrete ballast designs may take on a variety of different sizes, shapes and configurations depending on job-site
needs, installation approach and/or availability of production materials. Table G-2 below provides some typical
designs for concrete ballasts and details some suggested dimensional considerations based on pipe size, density
3
of unreinforced concrete at 144 lbs/ft and percent air entrapment in a typical underwater installation. These
dimensions are intended for reference purposes only after a careful analysis of the proposed underwater
installation in accordance with the guidelines presented in the PPI Engineering Handbook Chapter on Marine
Applications has been completed.
16
Plastics Pipe Institute. Marine Applications, 2004.
G-4
PolyPipe 12/05
Table G-2
SUGGESTED CONCRETE WEIGHT DIMENSIONS
Nominal
Pipe
Size,
IPS
Actual
OD,
inches
3”
4”
5”
6”
7”
8”
10”
12”
13”
14”
16”
18”
20”
22”
24”
28”
36”
42”
3.50
4.50
5.56
6.63
7.13
8.63
10.75
12.75
13.38
14.00
16.00
18.00
20.00
22.00
24.00
28.00
36.00
42.00
1.
2.
3.
4.
5.
6.
7.
8.
Weight Spacing to
Offset % of Air, feet
10%
15%
20%
10
10
10
10
10
10
10
10
10
15
15
15
15
15
15
20
20
20
6¾
6¾
6¾
6¾
6¾
6¾
6¾
6¾
6¾
10
10
10
10
10
13 ½
13 ½
13 ½
13 ½
5
5
5
5
5
5
5
5
5
7½
7½
7½
7½
7½
7½
10
10
10
Approx.
Weight of
Concrete
Block, lbs.
In
In Air
Water
12
20
30
35
45
55
95
125
175
225
250
360
400
535
610
900
1430
1925
7
10
18
20
26
30
55
75
100
130
145
210
235
310
360
520
830
1125
Bolt
Dimensions,
inches
Approximate Block Dimensions, inches
D
X
Y
T
S,
min
W
Dia.
Length
4
5
6
7⅛
7⅝
9¼
11 ¾
13 ¼
13 ⅞
14 ½
16 ½
18 ½
20 ½
22 ½
24 ½
28 ½
36 ½
42 ½
9
11
12
13
13 ½
15 ¼
19 ¼
21 ¼
24
24 ½
26 ½
28 ½
30 ½
34 ½
36 ½
40 ¼
48 ½
54 ½
3¾
4¾
5¼
5¾
6
6⅞
8⅝
9⅝
11
11 ¼
12 ¼
13 ¼
14 ¼
16 ¼
17 ¼
19 ¼
23 ¼
26 ¼
2½
2½
3½
3½
4¼
4¼
4½
5
5¼
6½
6½
8¼
8¼
8½
8¾
11 ¼
13 ½
15
1½
1½
1½
1½
1½
1½
2
2
2
2
2
2
2
2
2
2
2
2
2½
3
3
3
3
3
4
4
5
5
5
5
6
6
6
6
6
6
¾
¾
¾
¾
¾
¾
¾
¾
¾
1
1
1
1
1
1
1
1
1
12
12
12
12
12
12
12
13
13
13
13
13
13
13
13
13
13
13
Suggested underpad material: 1/8” black or red rubber sheet, or ¼” neoprene sponge padding. Width should be “T” + 2” minimum to
prevent concrete from contacting pipe surface.
Concrete interior should be smooth (3000 psi – 28 days)
Steel pipe sleeves may be used around the anchor bolts (1” for ¾” bolt, etc.). Hot dip galvanize bolts, nuts, washers and sleeves.
A minimum gap, “S”, between mating blocks must be maintained to allow for tightening on the pipe.
To maintain their structural strength some weights are more than the required minimum.
Additional weight may be required for tide or current conditions.
Weights calculated for fresh water.
All concrete blocks should be suitably reinforced with reinforcing rod to prevent cracking during handling, tightening and movement of
weighted pipe.
Figure G-1
SCHEMATICS OF CONCRETE BALLAST DESIGNS
G-5
PolyPipe 12/05
Figure G-2
TYPICAL DETAIL OF CONCRETE BALLAST SHOWING
1” GAP BETWEEN BALLAST SECTIONS
For additional information on the design considerations for marine applications, refer to the Plastics Pipe Institute
(PPI) Engineering Handbook chapter on Marine Applications. This document is available via download from the
PPI website www.plasticpipe.org.
NOTICE:
®
G-6
PolyPipe 12/05
SLURRY APPLICATIONS
Slurry is defined as a two-phase mixture of a solid in a fluid where the two constituents do not react chemically but
can be mechanically separated. There are two basic types of slurry. The first being a non-settling slurry in which
all particles remain entrained in the liquid. In this type of flow, the slurry resembles characteristics of a viscous fluid
and can be treated as such in the design of the system. The second and more typical flow regime for slurries is the
settling slurry. In this condition, the particles, once suspended in the liquid, begin to settle on the lower portion of
the pipe. The degree of settling is dependent upon the velocity of the system. Larger particles are harder to
suspend and require higher velocities to remain in suspension, especially in horizontal pipes.
The critical velocity, Vc, is defined as the minimum velocity required for suspension of the solids constituting the
slurry. The critical velocity is dependent on the following system variables:
Solid size and shape
Solid size distribution
Solid density
Fluid density
Slurry concentration
Size of the pipe
FLOW REGIMES
In order to make use of the benefits of PolyPipe® in slurry applications, it is useful to understand the phenomenon
of abrasion caused by the different types of slurry. There are four flow types that can exist in a slurry line, all of
which are the result of variances in the flow rates. Therefore, changes in the velocity can bring about any of the
flow conditions shown below:
1. Homogenous
All of the particles are evenly distributed and entrained in the fluid resulting in minimal contact between the
solid and the pipe wall. This condition is the least abrasive to the pipe material; therefore, the most
desirable.
2. Heterogenous
In this case, there is some tendency to settle toward the bottom of the pipe resulting in increased density of
the slurry in the bottom half of the pipe. However, the solids are still not in full contact with the pipe wall
while in transit; therefore, minimal abrasion occurs. This condition is the most economical since achieving
homogenous flow requires more energy.
3. Saltation
®
Solid particles tend to bounce on the bottom of the pipe causing abrasion in steel pipe, but in PolyPipe
solids rebound due to the characteristics of the piping material resulting in lower wear rates.
4. Sliding Bed
This is the most aggressive condition, where particles have fallen out of suspension and are being rolled
and dragged along the bottom of the pipe. In this case, very high degrees of abrasion occur especially in
the bottom quadrant of the pipe.
Increasing or decreasing the flow velocity can accomplish the transition between flow conditions described above.
For example, a slurry application in the saltation flow can be improved to heterogenous flow by increasing the flow
velocity. It should, however, be borne in mind that increasing the flow velocity is achieved at an increased cost.
This should be taken into consideration when costing out the installation.
H-1
PolyPipe 12/05
PARTICLE SIZE
For an application in which the particle size is very fine (such as fly-ash), the solid phase forms a viscous fluid with
the liquid carrier and demonstrates homogenous flow. This condition exists so long as the fluid velocity is
maintained above the critical velocity. When the velocity drops below the critical transition level, the solids begin to
settle and the flow condition changes from turbulent flow to one of laminar flow. In the laminar flow condition, the
slurry assumes the saltation or the sliding bed flow condition. Therefore, for this type of slurry, it is important to
maintain the flow rate at a level above the critical transition velocity in order to avoid significantly higher wear rates.
Typical types of material for which this consideration is of importance are those with particle sizes below 200
microns. These can include the following material types:
Boiler fly ash
Fine sands
Clays
Scrubber solids
Pulverized coal
Materials that have been reduced to powder
For slurries containing fine materials, as represented above, two-phase separation can be caused by the following
changes in the system:
1. Increase in slurry viscosity
2. Increase in solids concentration
3. Decrease in particle size
In each of the above cases, an increase in the flow velocity can prevent settling from occurring.
An application in which the particle size is not below 200 microns requires a different consideration. Larger,
heavier particles behave differently in suspension than the finer slurries and will not form homogenous flow
situations. For such materials, the best situation that can be achieved is the heterogenous flow condition. Due to
the large size of the particle and its’ significant density, the inertia of the particle results in a falling of the solid
content through the fluid, even at high velocities. This condition is true for full flow conditions, resulting in a higher
concentration of the solids in the lower half of the pipe. Once the flow rate is below the critical velocity, the amount
of solids begins to increase in the bottom of the pipe resulting in an increase in the degree of wear that can take
place. In most cases, the critical velocity for larger particles is in the turbulent flow regime.
Typical slurry materials that are in this category include the following:
Mine tailings
Sand
Mineral ores
Crushed limestone
Gravel
Dredge materials
In the case of the slurry having larger, heavier particles the following changes can increase the tendency to "dropout" of suspension:
1.
2.
3.
4.
Increase in particle size
Increase in solids density
Increase in solids concentration
Employment of a larger pipe diameter
An increase in flow velocity can prevent “fall-out” of particles and maintain a heterogenous flow.
H-2
PolyPipe 12/05
FLUID VELOCITIES
Shown below, Table H-1, are suggested fluid velocities by particle size and pipe size to attain optimum service.
Table H-1
SUGGESTED FLUID VELOCITIES
Pipe Size
3 - 10 in
(76-254 mm)
10 - 28 in
(254-711 mm)
28 - 48 in
(711 - 1216 mm)
200 Micron to ¼ inch
7 - 10 ft/sec
(2.1 - 3.0 m/sec)
8 - 12 ft/sec
(2.4 - 3.7 m/sec)
10 - 15 ft/sec
(3.0 - 4.6 m/sec)
> ¼ inch
10 - 13 ft/sec
(3.0 - 4.0 m/sec)
12 - 16 ft/sec
(3.7 - 4.9 m/sec)
14 -18 ft/sec
(4.3 - 5.5 m/sec)
PARTICLE SIZE
For slurry applications, flow velocities below the critical level can result in very high wear rates possibly even
plugging of the line.
PRESSURE LOSS
The pressure loss of slurry in a piping system due to friction can be estimated by using the Hazen-Williams
equation from Section B, “Pressure Drop”. The calculated pressure drop, ΔPf, multiplied by the specific gravity of
the slurry will approximate the frictional pressure drop. This is represented by the following equation:
Δ PS = Δ P f ⋅ SG
Where
ΔPS
ΔPf
SG
=
=
=
(39)
Pressure loss due to friction for slurry, psi/100 ft.
Pressure loss due to friction, psi/100 ft., (Equation (6))
Specific gravity of slurry, (dimensionless)
NOTE: The value obtained by this calculation procedure can be no more accurate than the determination of the
specific gravity but is recognized as yielding safe estimates.
PolyPipe® high molecular weight polyethylene pipe has an extremely high resistance to abrasion caused by
slurries. When compared to traditional materials, PolyPipe® has a higher resistance. For example, PolyPipe® can
outlast steel by as much as 4 to 1 in a given situation. This factor is only one of the benefits of using PolyPipe® for
slurry applications; it is also lighter in weight and easier to install in areas where slurry lines are required.
Unfortunately, due to the significant number of variables involved with slurry applications, it is difficult to establish a
reference for abrasion rates of polyethylene pipe.
In addition, polyethylene pipe is easier to maintain and can be easily rotated once wear has taken place.
PolyPipe® recommends periodic rotation of the slurry pipeline. The frequency of the rotation depends on the
properties of the slurry mixture being transported through the pipeline.
NOTICE:
®
H-3
PolyPipe 12/05
OVERHEAD OR INTERMITTENTLY
SUPPORTED PIPELINES
Items of consideration in the installation of intermittently supported pipelines are:
1.
2.
3.
4.
5.
Supported spacing
Type of support
Temperature influence
Pipeline weight and sag
Installation
SAG
The amount of sag in mid-span depends upon the weight of the pipe per foot, including effluent. Figure J-1 gives
the recommended spacing for a mid-span deflection of one-quarter of an inch when full of water. However, in
situations where a dry gas is being carried, the indicated span can be doubled. When condensation occurs in the
pipeline, the liquid accumulates in the sag, unless the pipe is sloped; therefore, accelerating the sag due to the
increased weight. If less deflection is desired, new support spacing can be determined by multiplying the spacing
by the following correction factors:
1.
2.
3.
4.
0.67 for 0.05 inch (1.3 mm) deflection
Figure J-1
SUPPORT SPACING FOR INTERMITTENTLY SUPPORTED PIPELINES
J-1
PolyPipe 12/05
TEMPERATURE
Figure J-1 provides for design of spacing to accommodate temperature differentials the pipeline may experience.
An increase in temperature decreases the beam strength of the pipeline resulting in an increase in the amount of
sag.
Note: A pipeline operating at temperatures above 150ºF (65ºC) should have continuous support.
Figure J-1, however, does not take into consideration the additional sag that can take place due to thermal
expansion because of temperature increases. For this reason, the pipe temperature at the time of installation
becomes very important and final tie-ins should be made as near as possible to or above the operating
temperature. If a 100 ft. (30.5m) pipeline is installed and tied-in at 60ºF (16ºC) and operated at 120ºF (49ºC), as
much as a 7 inch (178 mm) increase in length may occur that will manifest itself as additional sag.
SUPPORT
Polyethylene is a relatively soft material and requires rather wide, padded surfaces for supports. A pipeline full of
water is approximately three (3) times the weight of an empty line or a line conveying gaseous materials. Support
for lines flowing full of water should be at least as wide in the longitudinal pipeline direction as one-half the pipe
outside diameter. The support should cradle the pipe for approximately 135 degrees, i.e., assuming the open pipe
end to be the face of a clock; the support should be at least from 4:00 to 8:00. Suspended piping should have 180
degrees of support, and if held tightly in a clamp type device, the support would be 360 degrees. Where metal
supports or bands are utilized, a resilient padding such as neoprene or rubber must be used to protect the pipe
from damage by the supports.
SPACING
The designer may wish to refer to Section D for further understanding of the effects of temperature on a pipeline.
For determination on support spacing, the following formula 11 can be used to estimate the distance between
anchor or support points:
Δy =
( (
)
)
0.0651⋅ π ⋅ ρ p D 2 − d 2 + ρ f ⋅ d 2 ⋅ L4
(
E⋅ D −d
4
4
)
(40)
or
(
( (
)
⎡
E ⋅ D 4 − d 4 ⋅ Δy
L=⎢
2
2
2
⎢⎣ 0.0651 ⋅ π ⋅ ρ p D − d + ρ f ⋅ d
Where
Δy
ρp
ρf
E
L
D
d
=
=
=
=
=
=
=
)
⎤
⎥
⎥⎦
1/ 4
)
(41)
Sag of pipe at the lowest point, feet
Density of pipe, lbs/ft3 (0.955 for HDPE)
Fluid density, lbs/ft3
Modulus of elasticity, lbs/in2
Distance between supports, feet
NOTE: As previously stated, a pipeline operating continuously at or above 150ºF should have continuous support.
11
J-2
PolyPipe 12/05
INSTALLATION
A buried piping system, by virtue of the continuous contact of the backfill material and the reduction of temperature
fluctuation due to environment, needs no further special consideration. Pipe-to-soil friction will effectively retain the
buried pipe in place. However, the above ground pipeline does not have these restraints; therefore, the thermal
expansion/contraction must be allowed for by different means. With a change in temperature, an amount of
expansion/contraction will occur, and it is necessary to ensure that this effect is accommodated for so that no
adverse effects are experienced.
Change in length of pipeline due to thermal changes can be accommodated for in one of the following ways:
1. The pipeline can be allowed to move freely as its physical restraints allow.
2. It may be anchored closely and tightly so that unit changes take place in the elasticity of the material rather
than transferring all the forces to one point.
3. Ends and changes in direction may be anchored and expansion loops installed at or near the midpoint of the
run.
An above ground pipeline should be placed in the shade, if possible, in order to minimize the effect of sun
influenced temperature; therefore, the amount of thermal expansion that occurs.
NOTICE:
®
J-3
PolyPipe 12/05
NATURAL GAS FLOW
Natural gas distribution piping shall be designed and installed in accordance with all applicable federal, state and
local codes. Current law limits the design pressure rating to 125 psig for plastic pipe used in distribution systems or
Class 3 or 4 locations. Please refer to the Code of Federal Regulations (CFR), Parts 186 – 199 for additional
information.
The inside surface of PolyPipe® is extremely smooth and has a very low coefficient of friction. HDPE’s flow
resistance is considerably less than that of steel pipe. There is minimal drag on the pipe wall and due to
polyethylene’s exceptional resistance to corrosion there is little deterioration of the piping surface due to the
presence of aggressive media, both inside and outside of the pipe. Polyethylene pipe will maintain these
advantages for its entire service life, up to 50 years or more.
Due to the physical properties of polyethylene and the extremely smooth bore surface, it would appear only natural
to assume that polyethylene pipe would have significantly higher flow capacity. While this would be true in water
service systems, where the flow is fully turbulent, it is not entirely true in gas service systems, where the flow is
partially turbulent. The initial flow capacities for polyethylene and steel are similar; however, as the pipe ages, the
steel pipe can begin to corrode. Once this happens, the flow capacity for the steel pipe begins to decrease
dramatically. Therefore, for comparison purposes of performance over the service lives of the two pipes,
polyethylene would provide for a longer life.
Steel and polyethylene pipe have similar flow capacities. It has been found that flow formulas developed for sizing
of steel pipe are applicable for sizing of polyethylene pipe. However, consideration must be given to differences in
inside diameter.
Table L-1
TYPICAL MAXIMUM FLOW RATES EXPERIENCED IN 60 PSI
NATURAL GAS DISTRIBUTION SYSTEMS
Nominal Inside Pipe Diameter,
Inches
2
3
4
6
10
Maximum Flow Rates,
Mcfh (thousand cubic feet per hour)
17.4
43.5
81.1
163
556
Any of the accepted gas flow equations used with steel pipe, such as Mueller, Pole, Weymouth, Spitzglass, or the
IGT Distribution Equation, can be used for calculations of polyethylene pipe flow capacities. It should be noted that
no direct formulas provide the proper modifier to account for the extremely low coefficient of friction, which is
characteristic of polyethylene. The IGT Distribution Equation 13, shown below, is thought to be representative of
polyethylene for most distribution design situations.
⎛
T
Q = ⎜⎜ 0.6643 ⋅ b
Pb
⎝
Where
Q
Tb
Pb
P1
P2
L
T
μ
d
SG
13
=
=
=
=
=
=
=
=
=
=
(
)
5
8
⎞ ⎡ P1 2 − P2 2 ⎤ 9
d3
⎟⎟ ⎢
⎥
4
1
⎞
⎠ ⎣ T ⋅ L ⎦ ⎛⎜
9
9 ⎟
SG
μ
⎜
⎟
⎝
⎠
(42)
Volumetric flow rate, MSCFH
Base temperature, oR (Rankine)
Base pressure, psia
Upstream pressure, psia
Downstream pressure, psia
Length of pipe section, feet
Average fluid temperature, oR (Rankine)
Viscosity, lb/ft-sec
Specific gravity, dimensionless
American Gas Association. Plastic Pipe Manual for Gas Service, 2001.
L-1
PolyPipe 12/05
In order to supply our customers with the best possible tools upon which to base a design decision, the formulae
that follow represent a sampling of other acceptable equations that can be utilized for the determination of gas flow
capacity. These include the Mueller, Weymouth, and Spitzglass 1 equations. They are as follows:
Mueller Equation:
2826 ⋅ d 2.725
Q=
SG 0.425
⎛ P12 − P2 2 ⎞
⎜
⎟
⎜
⎟
L
⎝
⎠
0.575
(43)
Weymouth Equation:
2034 ⋅ d 2.667
Q=
SG 0.5
Spitzglass Equation:
⎛ P12 − P2 2 ⎞
⎜
⎟
⎜
⎟
L
⎝
⎠
0 .5
⎡
⎤
2
2 0 .5 ⎢
5
⎥
d
3410 ⎛ P1 − P2 ⎞
⎜
⎟
⎢
⎥
Q=
⎟ ⎢ ⎛ 3 .6
SG 0.5 ⎜⎝
L
⎞
⎠ ⎜1 +
+ 0.03d ⎟ ⎥
⎢⎣ ⎝
d
⎠ ⎥⎦
(44)
0 .5
(45)
PIPE COILING
Over the last 30 years, the demanding growth of polyethylene pipe for natural gas distribution systems and the
technical advances in construction practice have greatly increased the need for longer continuous lengths of
product. Coiling of pipe in sizes up to 6” nominal OD are now standard practice and readily available. Standard
coil lengths of 150’, 250’, 500’, and even larger lengths in smaller diameters have become acceptable product.
Due to the flexibility of polyethylene gas pipe, it can be coiled in this manner without damage to the pipe. However,
it is prudent to advise that this can pose a safety concern if the pipe is allowed to uncoil in an uncontrolled manner.
Coiled polyethylene piping can store an incredible amount of potential energy that is released during the uncoiling
of the pipe. This is an extremely important safety issue. Therefore, we cannot over stress the importance of
cautious handling and installation of the piping regarding the safety of all concerned from off-loading the product to
®
field installation personnel. PolyPipe recommends the use of an uncoiling/rerounding device when handling
coiled polyethylene pipe.
PIPE CURVATURE
In the construction of long distance runs of piping it is often necessary to negotiate bends and/or curves. The
natural flexibility of polyethylene piping, as mentioned previously, allows runs of piping to be routed around
obstacles in a fairly tight radius. Therefore, with proper planning, trenches can be excavated in such a manner to
accommodate bends and/or curves that are within the capabilities of the pipe.
To determine the cold bend radius of polyethylene pipe, OD/t, refer to Section F, Underground Installation, Table F-1.
1
th
L-2
PolyPipe 12/05
INSTALLATION
Prior to installation, an inspection should be completed of the pipe. Surface damage can occur during construction
handling and the installation process. Significant damage may impair the performance capabilities of the pipeline.
The following guidelines, as taken from the PPI Engineering Handbook, may be used to assess surface damage
significance.
For pressure applications, surface damage or butt fusion misalignment should not exceed 10% of the minimum wall
thickness required for the pipeline’s operating pressure. Deep cuts, abrasions or grooves cannot be field repaired
by hot gas or extrusion welding. Excessive damage may require removal and replacement of the damaged
section. Misaligned butt fusions should be cut out and redone.
If damage is not significant, the shape of the damage may be a consideration. Sharp notches and cuts should be
dressed smooth so the notch is blunt. Blunt scrapes or gouges should not require attention. Minor surface
abrasion from sliding on the ground or insertion into a casing should not be of concern.
For proper installation of polyethylene pipe for gas service, please refer to the American Gas Association Plastic
Pipe Manual.
L-3
PolyPipe 12/05
Table L-2
PE2406 (YELLOW)
OD
Nominal
in.
1/2
3/4
1
1 1/4
1 1/2
2
3
4
Nominal ID
0.840
1.050
1.315
1.660
1.900
2.375
3.500
4.500
Weight
Minimum Wall
in.
mm.
in.
mm.
lb. per
foot
9
9.3
11
0.64
0.65
0.68
16.31
16.47
17.22
0.093
0.090
0.076
2.37
2.29
1.94
0.094
0.092
0.079
0.140
0.136
0.117
9
9.3
11
11.5
0.80
0.81
0.85
0.86
20.39
20.59
21.53
21.75
0.117
0.113
0.095
0.091
2.96
2.87
2.42
2.32
0.147
0.143
0.123
0.118
0.219
0.213
0.183
0.176
9
9.3
11
11.5
1.01
1.02
1.06
1.07
25.53
25.79
26.96
27.24
0.146
0.141
0.120
0.114
3.71
3.59
3.04
2.90
0.231
0.224
0.193
0.186
0.343
0.334
0.288
0.277
42.16
9
9.3
11
11.5
13.5
1.27
1.28
1.34
1.35
1.40
32.23
32.55
34.04
34.39
35.54
0.184
0.178
0.151
0.144
0.123
4.68
4.53
3.83
3.67
3.12
0.368
0.357
0.308
0.296
0.256
0.547
0.532
0.459
0.441
0.381
48.26
9
9.3
11
11.5
13.5
1.45
1.47
1.53
1.55
1.60
36.89
37.26
38.96
39.36
40.68
0.211
0.204
0.173
0.165
0.141
5.36
5.19
4.39
4.20
3.57
0.482
0.468
0.404
0.388
0.335
0.717
0.697
0.601
0.577
0.499
9
9.3
11
11.5
13.5
17
1.82
1.83
1.92
1.94
2.00
2.08
46.12
46.57
48.70
49.20
50.85
52.80
0.264
0.255
0.216
0.207
0.176
0.140
6.70
6.49
5.48
5.25
4.47
3.55
0.753
0.732
0.631
0.606
0.524
0.424
1.120
1.089
0.939
0.902
0.780
0.630
9
9.3
11
11.5
13.5
17
2.68
2.70
2.83
2.85
2.95
3.06
67.96
68.63
71.77
72.51
74.94
77.81
0.389
0.376
0.318
0.304
0.259
0.206
9.88
9.56
8.08
7.73
6.59
5.23
1.635
1.589
1.370
1.317
1.138
0.920
2.433
2.364
2.039
1.959
1.694
1.369
9
9.3
11
11.5
13.5
17
3.44
3.47
3.63
3.67
3.79
3.94
87.38
88.24
92.27
93.23
96.35
100.05
0.500
0.484
0.409
0.391
0.333
0.265
12.70
12.29
10.39
9.94
8.47
6.72
2.702
2.626
2.265
2.176
1.882
1.521
4.022
3.909
3.370
3.239
2.800
2.263
Actual
in.
mm.
21.34
26.67
33.40
60.33
88.90
114.30
SDR
kg. per
meter
L-4
PolyPipe 12/05
Table L-2 (cont'd)
PE2406 (YELLOW)
OD
Nominal
in.
5
6
7
8
Nominal ID
Actual
in.
mm.
5.563
6.625
7.125
8.625
141.30
168.28
180.98
219.08
Minimum Wall
SDR
Weight
in.
mm.
in.
mm.
lb. per
foot
kg. per
meter
9
9.3
11
11.5
13.5
17
4.25
4.29
4.49
4.54
4.69
4.87
108.02
109.09
114.07
115.25
119.11
123.68
0.618
0.598
0.506
0.484
0.412
0.327
15.70
15.19
12.85
12.29
10.47
8.31
4.130
4.014
3.461
3.326
2.876
2.324
6.146
5.973
5.151
4.949
4.280
3.458
9
9.3
11
11.5
13.5
17
5.06
5.11
5.35
5.40
5.58
5.80
128.64
129.92
135.84
137.25
141.85
147.29
0.736
0.712
0.602
0.576
0.491
0.390
18.70
18.09
15.30
14.63
12.46
9.90
5.857
5.693
4.909
4.717
4.079
3.296
8.716
8.472
7.305
7.020
6.070
4.905
9
9.3
11
11.5
13.5
17
5.45
5.50
5.75
5.81
6.01
6.24
138.35
139.72
146.10
147.61
152.56
158.41
0.792
0.766
0.648
0.620
0.528
0.419
20.11
19.46
16.45
15.74
13.41
10.65
6.775
6.584
5.677
5.456
4.717
3.812
10.082
9.799
8.449
8.119
7.020
5.673
9
9.3
11
11.5
13.5
17
6.59
6.66
6.96
7.04
7.27
7.55
167.47
169.14
176.85
178.69
184.67
191.76
0.958
0.927
0.784
0.750
0.639
0.507
24.34
23.56
19.92
19.05
16.23
12.89
9.927
9.649
8.320
7.995
6.913
5.586
14.774
14.359
12.381
11.898
10.287
8.313
Table L-3
PIPE WEIGHTS AND DIMENSIONS (CTS)
PE2406 (YELLOW)
OD
Weight
Nominal ID
OD
Size
in.
mm.
in.
mm.
lb. per
foot
kg. per
meter
1/2 x 0.090
0.625
15.88
0.43
11.03
0.065
0.097
3/4 x 0.090
0.875
22.23
0.68
17.38
0.096
0.142
1 x 0.090
1.125
28.58
0.93
23.73
0.126
0.188
1 x 0.099
1.125
28.58
0.92
23.24
0.137
0.205
NOTICE:
®
L-5
PolyPipe 12/05
HANDLING AND STORAGE
After the piping system has been designed and specified, the piping system components must be obtained.
Typically, project management and purchasing personnel work closely together so that the necessary components
are available when they are needed for the upcoming construction work.
UNLOADING INSTRUCTIONS
Before unloading the shipment, there must be adequate, level space to unload the shipment. The truck should be
on level ground with the parking brake set and the wheels chocked. Unloading equipment must be capable of
safely lifting and moving pipe, fittings, fabrications or other components.
WARNING: Unloading and handling must be performed safely. Unsafe handling can result in damage to
property or equipment, and be hazardous to persons in the area. Keep unnecessary persons away from
the area during unloading.
WARNING: Only properly trained personnel should operate unloading equipment.
UNLOADING SITE REQUIREMENTS
The unloading site must be relatively flat and level. It must be large enough for the carrier's truck, the load handling
equipment and its movement, and for temporary load storage. Silo packs and other palletized packages should be
unloaded from the side with a forklift. Non-palletized pipe, fittings, fabrications, manholes, tanks, or other
components should be unloaded from above with lifting equipment and wide web slings, or from the side with a
forklift.
HANDLING EQUIPMENT
Appropriate unloading and handling equipment of adequate capacity must be used to unload the truck. Safe
handling and operating procedures must be observed.
Pipe must not be rolled or pushed off the truck. Pipe, fittings, fabrications, tanks, manholes, and other components
must not be pushed or dumped off the truck, or dropped.
Although polyethylene-piping components are lightweight compared to similar components made of metal,
concrete, clay, or other materials, larger components can be heavy. Lifting and handling equipment must have
adequate rated capacity to lift and move components from the truck to temporary storage. Equipment such as a
forklift, a crane, a side boom tractor, or an extension boom crane is used for unloading.
When using a forklift, or forklift attachments on equipment such as articulated loaders or bucket loaders, lifting
capacity must be adequate at the load center on the forks. Forklift equipment is rated for a maximum lifting
capacity at a distance from the back of the forks. (See Figure M-1.) If the weight-center of the load is farther out
on the forks, lifting capacity is reduced.
Before lifting or transporting the load, forks should be spread as wide apart as practical, forks should extend
completely under the load, and the load should be as far back on the forks as possible.
WARNING: During transport, a load on forks that are too short or too close together, or a load too far out
on the forks, may become unstable and pitch forward or to the side, and result in damage to the load or
property, or hazards to persons.
Lifting equipment such as cranes, extension boom cranes, and side boom tractors, should be hooked to wide web
choker slings that are secured around the load or to lifting lugs on the component. Only wide web slings should be
used. Wire rope slings and chains can damage components, and should not be used. Spreader bars should be
used when lifting pipe or components longer than 20 feet.
WARNING: Before use, inspect slings and lifting equipment. Equipment with wear or damage that impairs
function or load capacity should not be used.
M-1
PolyPipe 12/05
Figure M-1
FORKLIFT LOAD CAPACITY
Unloading Large Fabrications, Manholes and Tanks
Large fabrications, manholes and tanks should be unloaded using a wide web choker sling and lifting equipment
such as an extension boom crane, crane, or lifting boom. The choker sling is fitted around the manhole riser or
near the top of the tank. Do not use stub outs, outlets, or fittings as lifting points, and avoid placing slings where
they will bear against outlets or fittings. Larger diameter manholes and tanks are typically fitted with lifting lugs.
WARNING: ALL lifting lugs must be used. The weight of the manhole or tank is properly supported only
when all lugs are used for lifting. Do not lift tanks or manholes containing liquids.
Pre-Installation Storage
The size and complexity of the project and the components, will determine pre-installation storage requirements.
For some projects, several storage or staging sites along the right-of-way may be appropriate, while a single
storage location may be suitable for another job.
The site and its layout should provide protection against physical damage to components. General requirements
are for the area to be of sufficient size to accommodate piping components, to allow room for handling equipment
to get around them, and to have a relatively smooth, level surface free of stones, debris, or other material that could
damage pipe or components, or interfere with handling. Pipe may be placed on 4-inch wide wooden dunnage,
evenly spaced at intervals of 4 feet or less.
Pipe Stacking Heights
Coiled pipe is best stored as received in silo packs. Individual coils may be removed from the top of the silo pack
without disturbing the stability of the remaining coils in the silo package.
Pipe received in bulk packs or strip load packs should be stored in the same package. If the storage site is flat and
level, bulk packs or strip load packs may be stacked evenly upon each other to an overall height of about 6 feet.
For less flat or less level terrain, limit stacking height to about 4 feet.
Before removing individual pipe lengths from bulk packs or strip load packs, the pack must be removed from the
storage stack, and placed on the ground.
Individual pipes may be stacked in rows. Pipes should be laid straight, not crossing over or entangled with each
other. The base row must be blocked to prevent sideways movement or shifting (See Table M-1). The interior of
stored pipe should be kept free of debris and other foreign matter.
M-2
PolyPipe 12/05
Table M-1
LOOSE PIPE STORAGE
Pipe Size,
Nominal
Suggested Stacking Height* - Rows
DR Above 17
DR 17 & Below
4
15
12
5
12
10
6
10
8
8
8
6
10
6
5
12
5
4
14
5
4
16
4
3
18
4
3
20
3
3
22
3
2
24
3
2
26
3
2
28
2
2
30
2
2
32
2
2
36
2
1
42
1
1
48
1
1
54
1
1
63
1
1
*NOTE: Stacking heights based on 6 feet for level terrain and 4 feet for less level terrain.
Exposure to UV and Weather
Polyethylene pipe products are protected against deterioration from exposure to ultraviolet light and weathering
effects. Color and black products are compounded with antioxidants, thermal stabilizers and UV stabilizers. Color
products use sacrificial UV stabilizers that absorb UV energy and are eventually depleted. In general, non-black
products should not remain in unprotected outdoor storage for more than two years; however, some manufacturers
may allow longer unprotected outside storage. Black products contain at least 2% carbon black to protect the
material from UV deterioration. Black products with and without stripes are generally suitable for unlimited outdoor
storage and for service on the surface or above grade.
Cold Weather Handling
Temperatures near or below freezing will affect polyethylene pipe by reducing flexibility and increasing vulnerability
to impact damage. Care should be taken not to drop pipe, or fabricated structures, and to keep handling
equipment and other things from hitting pipe. Ice, snow, and rain are not harmful to the material, but may make
storage areas more troublesome for handling equipment and personnel. Unsure footing and traction require
greater care and caution to prevent damage or injury.
Walking on pipe can be dangerous. Inclement weather can make pipe surfaces especially slippery.
WARNING: Keep safety first on the jobsite; do not walk on pipe.
All of the above information has been printed with permission of the Plastics Pipe Institute. The information is
available in the Engineering Handbook; Inspections, Test and Safety Concerns.
NOTICE:
®
M-3
PolyPipe 12/05
CONVERSION FACTORS
METRIC TO ENGLISH
To obtain:
Multiply:
By:
Inches
Inches
Feet
Yards
Miles
Ounces
Pounds
Gallons (U.S. Liquid)
Fluid Ounces
Square Inches
Square Feet
Square Yards
Cubic Inches
Cubic Feet
Cubic Yards
Pounds/Cubic Feet
Gallons/Minute
Centimeters
Millimeters
Meters
Meters
Kilometers
Grams
Kilometers
Liters
Milliliters (cc)
Square Centimeters
Square Meters
Square Meters
Milliliters (cc)
Cubic Meters
Cubic Meters
Kilograms/Cubic Meter
Cubic Meters/Minute
0.3937
0.03937
3.281
1.094
0.6214
352.74
2.205
0.264
338.14
0.155
10.764
1.196
610.24
35.315
1.308
0.0624
0.00378
ENGLISH TO METRIC
To obtain:
Multiply:
By:
Microns
Centimeters
Millimeters
Meters
Meters
Kilograms
Grams
Kilograms
Liters
Milliliters (cc)
Square Centimeters
Square Meters
Square Meters
Milliliters (cc)
Cubic Meters
Cubic Meters
Cubic Meters/Minute
Mils
Inches
Inches
Feet
Yards
Miles
Ounces
Pounds
Gallons (U.S. Liquid)
Fluid Ounces
Square Inches
Square Feet
Square Yards
Cubic Inches
Cubic Feet
Cubic Yards
Gallons/Minute
25.4
2.54
25.4
0.3048
0.9144
1.609
28.350
0.456
3.785
29.574
6.452
0.0929
0.936
16.387
0.02832
0.765
264.86
N-1
PolyPipe 12/05
GENERAL
To obtain:
Multiply:
By:
Atmospheres
Atmospheres
PSI
Atmospheres
Feet of water @ 4°C
Inches of mercury @ 0°C
Inches of mercury @ 0°C
Pounds per square inch
BTU
Foot-pounds
BTU
Joules
Cords
MPa
Pounds per Square Inch
Degree (angle)
Ergs
Feet
Feet of Water @ 4°C
Foot-pounds
Foot-pounds
Foot-pounds per minute
Horsepower
Inches of Mercury @ 0°C
Joules
Joules
Kilowatts
Kilowatts
Kilowatts
Knots
Miles
Nautical Miles
Radians
Square Feet
Watts
Pounds per Square Inch
Cubic Feet
MPa
Radians
Foot-Pounds
Miles
Atmosphere
Horsepower-hours
Kilowatts-hours
Horsepower
Foot-pounds per second
BTU
Foot-pounds
BTU per minute
Foot-pounds per minute
Horsepower
Miles per hour
Feet
Miles
Degrees
Acres
BTU per minute
Feet of water @ 4°C
0.0295
0.0342
.2049
0.06804
0.01285
0.09348
128
0.006897
145
57.2958
7
1.356 x 10
5280
33.90
6
1.98 x 10
6
2.655 x 10
6
3.3 x 10
1,818
2.036
1054.8
1.35582
0.01758
0.0000226
0.7457
0.869
0.0001894
0.869
0.01745
43,560
17.5796
0.4335
N-2
PolyPipe 12/05
TEMPERATURE FACTORS
T(°F) = 1.8T(°C) + 32
T(°C) = [T(°F) -32]/1.8
T(oR) = 1.8T(K)
T(K) = T(oC) + 273.15
T(oR) = T(oF) + 459.67
Centigrade scales and Celsius scales are interchangeable.
DECIMAL EQUIVALENTS OF FRACTIONS OF AN INCH
1/32
1/16
2/32
3/32
1/8
4/32
5/32
3/16
6/32
7/32
1/4
8/32
9/32
5/16
10/32
1/64
2/64
3/64
4/64
5/64
6/64
7/64
8/64
9/64
10/64
11/64
12/64
13/64
14/64
15/64
16/64
17/64
18/64
19/64
20/64
21/64
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
0.015
0.031
0.046
0.625
0.078
0.093
0.109
0.125
0.140
0.156
0.171
0.187
0.203
0.218
0.234
0.250
0.265
0.281
0.296
0.312
0.328
11/32
3/8
12/32
13/32
7/16
14/32
15/32
1/2
16/32
17/32
9/16
18/32
19/32
5/8
20/32
21/32
22/64
23/64
24/64
25/64
26/64
27/64
28/64
29/64
30/64
31/64
32/64
33/64
34/64
35/64
36/64
37/64
38/64
39/64
40/64
41/64
42/64
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
0.343
0.359
0.375
0.390
0.406
0.421
0.437
0.453
0.468
0.484
0.500
0.515
0.531
0.546
0.562
0.578
0.593
0.609
0.625
0.640
0.656
11/16
22/32
23/32
3/4
24/32
25/32
13/16
26/32
27/32
7/8
28/32
29/32
15/16
30/32
31/32
43/64
44/64
45/64
46/64
47/64
48/64
49/64
50/64
51/64
52/64
53/64
54/64
55/64
56/64
57/64
58/64
59/64
60/64
61/64
62/64
63/64
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
0.671
0.687
0.703
0.718
0.734
0.750
0.765
0.781
0.796
0.812
0.828
0.843
0.859
0.875
0.890
0.906
0.921
0.937
0.953
0.968
0.984
NOTICE:
®
N-3
PolyPipe 12/05
MATERIAL SAFETY DATA SHEET
SECTION 1 - IDENTIFICATION
Yellow MDPE Pipe
All Other Products
3810 PE2406 Gas Pipe
Trade Name:
Warning:
Trade Name:
Do not use for potable water.
Classification:
ASTM D3350
PE234363E
Classification:
ASTM D3350
ASTM D1248
(obsolete)
Type II, Class B, Category 5,
Grade P23/P24
ASTM D1248
(obsolete)
PolyPipe® EHMW, PolyPlus™,
Lightview™, 7810 Gas Pipe,
6810 Gas Pipe, 4810 Gas Pipe,
PolyPipe® PW
PE234463C, D or E (2406)
PE345464C, D or E (3408)
Type II, Class B, Category 5,
Grade P23/P24 (2406)
Type III, Class C, Category 5,
Grade 34 (3408)
SECTION 2 – PHYSICAL DATA
Yellow MDPE Pipe
All Other Products
2a
Appearance:
2b
2c
2d
2e
2f
2g
2h
2i
2j
Odor:
Boiling Point:
Solubility:
Evaporation:
Density:
Vapor Pressure:
Melting Point:
Vapor Density:
Percent Volatile:
½” – 24” diameter yellow
pipe either coiled or cut
to length
Odorless
N/A
Insoluble in water
N/A
0.943 g/cm3 @ 230C
N/A
230 – 275oF
N/A
Negligible
2a
Appearance:
2b
2c
2d
2e
2f
2g
2h
2i
2j
Odor:
Boiling Point:
Solubility:
Evaporation:
Density:
Vapor Pressure:
Melting Point:
Vapor Density:
Percent Volatile:
½” – 54” diameter black or
colored pipe either coiled or
cut to length
Odorless
N/A
Insoluble in water
N/A
0.947 - 0.960 g/cm3 @ 230C
N/A
230 – 275oF
N/A
<0.03%
SECTION 3 – HEALTH HAZARD INFORMATION
Yellow MDPE or Colored HDPE Pipe
Black Products
3a
Hazardous Components:
Lead Chromate Pigment – CAS # 1344-37-2
Lead Chromate – CAS # 7758-97-6
Cadmium – CAS# 7440-43-9
3b Exposure Limits:
OSHA Permissable Exposure Limit:
5 mg/m3 respirable dust
15 mg/m3 total dust
Cadmium
5μg/m3 cadmium
15 mg/m3 total dust
Lead and
3
Chromium 0.5 mg/m chromium
0.05 mg/m3 lead
3a
Hazardous Components:
Carbon black– CAS # 1333-86-4
3b
Exposure Limits:
OSHA Permissable Exposure Limit:
15 mg/m3 total dust
ACGIH limits exposure to 10mg/m3 total dust.
PolyPipe® yellow gas products may contain either lead Avoid breathing dust or fumes that may be generated
chromate or cadmium. Both of these products are during cutting or fusing of pipe.
known to be a probable human carcinogen.
3c Overexposure:
Repeated and prolonged exposure to dust or fumes that may be generated during cutting and fusing of
pipe may cause delayed effects involving blood, gastrointestinal, nervous and reproductive systems.
See Section 4 for Emergency First Aid Procedures.
P-1
PolyPipe 12/05
SECTION 4 – EMERGENCY AND FIRST AID PROCEDURES
Yellow MDPE Pipe
All Other Products
4a
4b
Inhalation:
The material is not expected to present an acute
inhalation hazard. If exposed to fumes from
overheating or combustion, move to fresh air.
Consult a physician if symptoms persist.
Eyes:
4a
4b
Immediately flush polymer fines from eyes with
water for several minutes; seek medical attention.
4c
Skin:
4c
Cool skin rapidly if contacted with molten polymer
without attempting to remove molten material.
Obtain medical attention for thermal burns.
4d
Ingestion:
Products containing cadmium are harmful if
ingested due to the toxicity of cadmium. Seek
medical attention.
4d
Inhalation:
The material is not expected to present an acute
inhalation hazard. If exposed to fumes from
overheating or combustion, move to fresh air.
Consult a physician if symptoms persist.
Eyes:
Immediately flush polymer fines from eyes with
water for several minutes; seek medical
attention.
Skin:
Cool skin rapidly if contacted with molten
polymer without attempting to remove molten
material. Obtain medical attention for thermal
burns.
Ingestion:
Few or no adverse health effects from ingestion.
Seek medical attention if pain develops.
SECTION 5 – FIRE AND EXPLOSION DATA
Yellow MDPE Pipe
All Other Products
5a
5b
5c
5d
5e
5f
5g
>650oF (ASTM E136)
Flash Point:
Upper Explosive
Not determined
Limit:
Lower Explosive
Not determined
Limit:
Auto ignition
>650oF (estimated)
temperature
Extinguishing Media
Dry chemical, water fog, foam, carbon dioxide
Special fire & explosion hazards
Dense smoke emitted when burned without
sufficient oxygen. Possible dust explosion if
fines accumulate. Wear standard fire fighting
equipment.
NFPA Ratings
Health 1; Flammability 1; Reactivity 0
5a
5b
5c
5d
5e
5f
5g
>650oF (ASTM E136)
Flash Point:
Upper Explosive
Not determined
Limit:
Lower Explosive
Not determined
Limit:
Auto ignition
>650oF (estimated)
temperature
Extinguishing Media
Dry chemical, water fog, water spray, foam,
carbon dioxide
Special fire & explosion hazards
Dense smoke emitted when burned without
sufficient oxygen. Possible dust explosion if fines
accumulate.
Wear standard fire fighting
equipment.
NFPA Ratings
Health 0; Flammability 1; Reactivity 0
SECTION 6 – ACCIDENTAL RELEASE MEASURES
All Products
6a
6b
6c
6d
Environmental Precautions:
Prevent discharges of spilled material with mixing in soil and prevent runoff to surface waters. Avoid
creating dust and prevent wind dispersion.
Land Spill:
Spilled material should be swept up and discarded. Comply with applicable federal, state and local
regulations.
Water Spill:
Advise local authorities if spilled in waterway or sewer. Skim from surface of water if possible.
Waste Disposal:
Dispose in accordance with federal, state and local regulations.
P-2
PolyPipe 12/05
SECTION 7 – STORAGE AND HANDLING
All Products
7a
7b
7c
Do not store pipe near heat, flame or strong oxidants, such as chlorates, nitrates, peroxides, etc. May
react with halogens.
See 9d below for incompatibility with other materials.
Maximum recommended storage life for yellow PE2406 3810 Gas Pipe or other colored products,
excluding black, is three years from date of manufacture.
SECTION 8 – PROTECTIVE MEASURES
All Products
8a
8b
Cleanup Procedures:
Waste Disposal Method:
8c
Respiratory Protection:
8d
8e
Protective Clothing:
Ventilation:
Sweep and collect in suitable container for disposal.
This product is not considered a RCRA hazardous waste. Dispose of in
accordance with local, state and federal regulations.
Use NIOSH approved respirator if unable to control airborne dust, fumes or
vapors.
Wear gloves and suitable eye protection.
Local exhaust ventilation is recommended for control of airborne dust, fumes
and vapors, particularly in confined areas.
SECTION 9 – REACTIVITY
All Products
9a
9b
9c
9d
9e
Stability:
Hazardous
Polymerization:
Conditions to Avoid:
Incompatibility with
Other Materials:
Combustion Products:
Material is stable.
Hazardous polymerization will not occur.
Avoid prolonged exposure to temperatures over 480oF (250oC). Do not heat
without proper ventilation.
Avoid storage or contact with strong oxidizing agents.
Combustion products generated during processing include: carbon dioxide,
carbon monoxide, water vapor and trace amounts of volatile organic
compounds. Carbon monoxide is highly toxic if inhaled. Carbon dioxide in
sufficient concentrations can act as an asphyxiant. Acute overexposure to
the products of combustion may result in irritation of the respiratory tract.
PolyPipe® urges the customer receiving this Material Safety Data Sheet to study it carefully to become aware of
potential hazards, if any, of the products involved. In the interest of safety you should (1) furnish your employees,
agents and contractors with this sheet, (2) furnish a copy to each of your customers for their product and (3)
request your customer to inform their employees and customers as well.
CHEMTREC EMERGENCY NUMBER
(800) 424-9300
NOTE: Hazard data contained herein was obtained from raw material suppliers.
TO THE BEST OF OUR KNOWLEDGE THE INFORMATION CONTAINED IN THIS MATERIAL SAFETY DATA
SHEET IS ACCURATE. HOWEVER, NEITHER PolyPipe, Inc., NOR ANY OF ITS AFFILIATES MAKE ANY
WARRANTY, EXPRESS OR IMPLIED, OR ACCEPTS ANY LIABILITY IN CONNECTION WITH THIS
INFORMATION OR ITS USE.
P-3
PolyPipe 12/05
★
★
★
★
★ ★
GAINESVILLE PLANT
ERWIN PLANT
ROARING SPRINGS PLANT
P.O. Box 390
2406 N. I-35
Gainesville, TX 76241-0390
(940) 665-1721
(800) 433-5632
Fax: (940) 668-8612
Sales Fax: (940) 668-2704
P.O. Box 199
1050 Industrial Drive South
Erwin, TN 37650
(423) 743-9116
Fax: (423) 743-8419
P.O. Box 298
11000 Hwy. 70 South
Roaring Springs, TX 79256
(806) 348-7551
(877) 771-8330
Fax: (806) 348-7905
FERNLEY PLANT
SANDERSVILLE PLANT
KIMBALL PLANT
230 Lyon Drive
Fernley, NV 89408
(775) 575-5454
Fax: (775) 575-6960
P.O. Box 784
995 Waco Mill Road
Sandersville, GA 31082
(478) 553-0576
3405 PolyPipe Road
Kimball, NE 69145
(308) 235-4828
Fax: (308) 235-2938
©
PolyPipe® is an active member of the Plastics Pipe Institute,
AWWA, AGA and ASTM.
ISO 9001:2000
PolyPipe, Inc.
2406 N. I-35 I P.O. Box 390 I Gainesville, TX 76241
Phone 940.665.1721 I 800.433.5632 I Facsimile 940.668.8612
Sales Facsimile 940.668.2704 I www.polypipeinc.com
C-1000
Rev. 05/05

PE Pipe Design and Engineering Guide (PolyPipe)

Transcription

Similar documents

Hymax Couplings 1.5

Fernco Flexible Coupling Installation - Fernco

Fernco Flexible Coupling Installation - Fernco

great lengths - Laney Directional Drilling

LGOBO SALE SHEET

10` x 10` Gazebo

WK9_Day4 - Javy Galindo

At the annual Gem-O-Rama gem and mineral

Daniel J. Grasse, B.Sc., L.LB. The 1930`s:

HYMAX® by Krausz Wide-Range Coupling Solutions