Determining Tube Size for Hydraulic Systems

Determining Tube Size for Hydraulic Systems

Step 2: Determine Tube
Determining Tube Size
for Hydraulic Systems
0.0. and
Wall Thickness
Using Tables U15 and U16, determine the tube 0.0. and wall
thickness combination that satisfies the following two conditions:
Proper tube material, type and size for a given application and
type of fitting is critical for efficient and trouble free operation of
the fluid system. Selection of proper tubing involves choosing
the right tube material, and determining the optimum tube size
(0.0. and wall thickness).
A.
Has recommended design pressure equal to or higher than maximum operating pressure.
B.
Provides tube 1.0. equal to or greater than required flow
diameter determined earlier.
Proper sizing of the tube for various parts of a hydraulic system
results in an optimum combination of efficient and cost effective
performance.
Design pressure values in Tables U15 and U16 are based on
the severity of service rating "A" (design factor of 4) in Table
U10, and temperature derating factor of 1 in Table U11.
A tube that is too small causes high fluid velocity, which has
many detrimental effects. In suction lines, it causes cavitation
which starves and damages pumps. In pressure lines, it causes
high friction losses and turbulence, both resulting in high
pressure drops and heat generation. High heat accelerates
wear in moving parts and rapid aging of seals and hoses, all
resulting in reduced component life. High heat generation also
means wasted energy, and hence, low efficiency.
If more severe operating conditions are involved, the values in
Tables U15 and U16 should be multiplied by appropriate
derating factors from Tables U1 0 and U11 before determining
the tube 0.0. and wall thickness combination. Contact the
Tube Fittings Division when in doubt.
Allowable design stress levels and formula used to arrive at the
design pressure values are given in the following chart. Values
in Table U8 are for fully annealed tubing.
Too large of a tube increases system cost. Thus, optimum tube
sizing is very critical.Strength
The
following
is a simple procedure for
Low
(HSLA)
ASTM
875
J2467
J525
304
&6061-T6
316Alloy
Stainless
Steel
Material
andMonel,
Type
Steel,
High
Aluminum
Alloy
Steel
C-4130
sizing the tubes.
400
Steel
Steel
C-1
021
C-1
010
Copper, K or Y
ASTM
J528,
A213,
SAE
J356,
J524,
SAE
J2435,
ASTM
A519
8165
8210
72°F
Factor
of18,800
4
at
Tube
6,000
PSI
Stress
fo
Design
17,500
10,500
PSI
PSI
PSI
15,000
12,500
PSI
18,000
Specification
Allowable
J2614
18,800
PSIDesign
A249,A269
SAE J2613,
Step 1: Determine Required Flow Diameter
Use Tables U13 and U14 to determine recommended
diameter for the required flow rate and type of line.
The table is based on the following recommended
ties:
flow
flow veloci-
Pressure lines - 25 ft./sec. or 7.62 meters/sec.
Return lines - 10 ft./sec. or 3.05 meters/sec.
Suction lines - 4 ft./sec. or 1.22 meters/sec.
If you desire to use different velocities than the above, use one
of the following formulae to determine the required flow diameter.
Flow in GPM
Tube 1.0. (in.) = 0.64
Velocity in fUsee.
OR
Tube 1.0. (mm) = 4.61
Flow in liters per minute
Table U8 -
Design Stress Values
Velocity in meters/sec.
Design Pressure Formula (LAME'S)
P=S
02 _-d_2_)
+ d2
(_0_2
where:
o = Outside diameter of tube, in
d = Inside diameter of tube (D-2T), in
P = Recommended design pressure, psi
S = Allowable stress for design factor of 4, psi
T = Tube wall thickness, in.
Table U9 -
Design Pressure Formula
For thin wall tubes (DIT ~ 10) the following formula may be
Used: P = 2ST/D
Recommended Flow Diameters - In Inches
0.169
0.143
0.128
0.181
0.202
0.222
0.239
0.395
0.286
0.300
0.314
0.326
0.339
0.351
0.362
0.373
0.384
0.064
0.091
0.111
0.256
0.272
0.558
0.543
0.528
0.512
0.462
0.496
0.443
0.425
0.405
2.170
2.263
2.373
2.024
0.903
0.990
2.123
0.880
2.479
0.857
2.074
0.833
0.808
0.728
0.782
0.700
0.756
0.479
0.286
0.319
0.350
0.267
0.623
0.670
0.404
0.429
0.639
0.452
0.474
0.495
0.515
0.534
0.553
0.589
0.226
0.202
0.101
0.143
0.175
0.868
1.428
0.905
1.030
0.677
0.701
1.693
0.724
1.278
0.810
1.973
1.245
0.789
1.920
1.212
0.768
1.866
1.178
0.746
0.572
0.600
0.627
1.340
0.849
1.498
0.949
1.565
0.991
1.309
0.830
0.453
0.506
0.554
0.423
0.986
0.599
0.378
0.392
0.247
0.640
0.679
0.750
0.784
0.816
0.847
0.876
0.933
0.358
0.320
0.160
0.277
Lines
1.370
1.069
1.106
1.431
1.568
1.395
1.358
1.154
1.109
1.061
1.319
1.280
1.239
1.197
Pressure
Return
in Inches
0.157
Suction
Lines
2.217
0.947
0.571
0.606
1.399
0.887
0.653
1.632
1.753
1.810
1.143
0.716
0.960
1.501
1.012
Recommended Flow Diameter
170.00
130.00
75.00
200.00
140.00
160.00
180.00
190.00
100.00
110.00
120.00
95.00
90.00
85.00
80.00
70.00
GPM
150.00
65.00
Flow Rate Maximum
ximum
Table U13 -
Recommended Flow Diameters, in Inches
Lines
1.248
1.214
1.145
1.109
1.071
1.032
1.180
2.303
2.390
2.555
2.634
2.213
2.020
2.119
2.862
2.710
2.784
4.525
2.857
3.119
3.036
2.950
2.771
2.677
2.580
Pressure
3.649
1.515
3.786
3.919
4.048
1.669
4.172
1.717
4.293
1.764
4.411
1.969
3.505
1.459
1.280
3.200
1.342
3.356
1.402
1.807
1.749
1.690
1.629
1.810
Lines
in
Inches
2.474
1.568
1.619
1.916
1.862
Suction
Return
Recommended
Flow Diameter
Inch Tube Pressure Ratings
Steel
1021
Thick.
Wall
I.D.
11950
11000
2050
2200
9400
2600
5500
3700
8000
4750
6550
6900
1700
8300
9350
3550
7900
7400
8200
6700
6500
9600
8650
3900
5350
3050
2400
6650
9650
5100
11050
0.245
0.058
0.049
0.204
0.124
0.090
0.105
0.010
4600
0.085
0.020
0.210
3100
6650
0.069
0.118
0.168
5750
0.152
0.134
0.148
4250
0.132
7800
0.120
0.065
0.209
0.083
7600
0.185
0.095
6850
0.169
0.072
0.084
0.273
0.109
0.231
5400
0.197
8000
0.335
2450
0.257
0.215
6450
0.282
9150
0.123
0.260
0.402
0.384
0.370
0.356
4800
0.334
0.259
0.277
2550
0.305
0.188
7850
5450
1400
6550
5000
3250
4450
8050
8950
1500
11800
12050
10800
10000
10400
3250
6900
5950
8200
4450
6400
9250
8450
7550
9750
4050
6150
5500
7200
3850
13200
15000
2550
13800
2800
3000
8350
13450
2700
2400
2150
3150
2950
3100
2300
1050
1400
1150
1550
1750
3300
3650
3850
4300
700
950
Steel
Tube
10150
10500
10750
9100
1800
6000
2950
7750
3250
4900
4400
5750
13250
5400
2150
0.194
0.028
3950
0.180
0.035
8450
0.055
6900
6150
0.183
0.444
9950
8750
0.157
0.430
0.147
0.243
4500
2700
4100
3650
2000
0.319
5550
0.310
0.232
2950
5600
7200
1700
1850
11750
11450
10350
12150
2100
2200
4650
8650
9900
6750
4850
6650
12700
8150
3650
5550
16600
2600
2050
2100
2650
2200
2750
1500
1900
1300
1950
1200
4050
3200
4200
4800
4400
3750
3450
5300
650
800
900
304
1010
&HSLA
316,
4130,
(in.)
(in.)
Copper
Inch Tubes*
1.000
1.000
0.875
0.625
0.625
0.750
0.875
1.000
0.625
0.750
Stai
n less
Tube
a.D.
(4:1 Design Factor),
PSIPressure
(in.)
Design
* See Table U8 for tube specifications.
Table U15 -Inch
Tube Pressure Ratings
Steel Tubes*
1100
2350
4000
3600
4550
5350
2700
1850
1450
7600
3050
3400
3850
5200
6250
6050
1800
9000
2650
3100
4200
4700
2800
3200
3650
5000
5300
0.109
0.156
0.083
0.188
0.134
4150
0.560
0.760
5500
3000
3800
0.870
0.704
0.856
2250
6350
2100
0.527
2550
0.065
3200
0.481
3750
0.459
0.083
0.095
0.385
5200
0.805
0.652
5050
0.109
0.454
0.745
0.569
7500
0.510
2200
0.657
0.607
0.620
3050
1750
1300
1500
11300
1150
2200
9800
5050
8250
6350
3900
3200
4300
Wall
5650
6550
7600
6900
8700
1550
3000
6600
5250
3150
3550
3950
2150
2500
1800
1000
550
750
950
2100
7850
6600
1550
2500
4500
6700
1250
2400
1400
4250
5050
5900
5500
7000
Tube
0.120
0.065
0.095
0.072
0.049
0.220
0.148
4200
0.058
0.035
4900
0.028
4600
4400
6550
3350
0.624
0.782
0.732
4450
0.688
2600
0.810
0.884
0.834
0.902
0.680
0.357
0.930
0.509
2850
0.495
0.072
4350
0.435
5600
0.120
0.482
0.579
0.555
0.049
0.407
5800
0.777
2000
0.374
0.532
0.759
0.731
0.709
0.685
3500
3900
0.635
0.634
2350
2650
0.606
0.584
3550
1550
1950
1200
1050
2300
4550
5700
6700
2900
3400
1950
1850
9550
900
1
7350
3800
4800
8450
7800
6200
2650
3350
4500
5850
1750
4600
5350
350
2650
2000
2100
2800
3150
3050
2350
2700
2450
2200
1700
1600
1450
1250
1100
1200
1350
1550
1050
1650
1850
1150
600
450
500
850
700
3600
1021
Steel
Steel
Thick.
J.D.
1010
2600
4130,
304
&
HSLA
316,
(in.)
(in.)
Inch
Copper
Stainless
(4:1 Design Factor),
DesignPSI
Pressure
Inch Tube Pressure Ratings (cont'd.)
SteelTubes*
. Inch
7250
2050
2350
2950
2600
3400
3250
2850
2700
2450
2150
0.156
0.148
1950
1700
1.204
1.232
1.260
1.310
1.188
1.282
0.109
4300
4050
3650
2550
3250
2950
0.095
1350
1050
1300
800
1021
1000
2100
2150
1500
6100
2400
2500
3550
3950
4200
1900
3650
2800
4800
2450
1600
1450
1200
1400
1750
5150
3200
3050
1300
5750
1800
5000
0.810
Tube
·0.072
2000
2650
2550
2350
0.220
4150
4800
3500
0.065
0.072
2100
0.134
0.120
3050
0.109
4000
2050
0.250
0.058
0.049
0.083
1150
1250
5100
1450
4300
2950
0.982
0.954
0.938
1600
1800
1100
1750
1500
1200
1000
0.281
1.060
1350
1.370
1.356
1.334
1.704
1.732
1.010
1.782
1.500
1.560
1.032
1.810
1.438
1.856
1.000
1.870
1.120
1.134
1.152
1.760
1.624
1.084
1.124
1.688
850
950
0.22
·0.083
2050
2200
2400
2150
1.834
2300
4950
1600
1.106
1700
1900
7700
4450
2700
3950
3850
4600
1400
1250
6300
1850
1550
6450
3000
3150
5250
3550
6000
2650
5300
0.188
I.D.
2450
2050
2300
2000
1250
1400
1000
1700
1450
1150
1900
1600
450
550
600
500
400
950
700
750
850
650
.1150
Steel
Thick
0.188
O~
O.148
0.095
3300
0.083
3050
Wall
0.874
0.220
188
..
1010
304
0.156
&
316,
Stain less
4130,
HSLA
(in.)
(in.)
Copper
Design
(4: 1 Design Factor),
PSI Pressure
,.,
,,
...... ...
.
-
...
* See Table U8 for tube specifications.
Table U15 ~ Inch Tube Pressure Ratings, cont'd.
Recommended Flow Diameters - In Millimeters
1.670
2.362
2.893
5.010
3.340
4.723
3.734
4.418
10.295
16.277
10.020
11.203
12.385
13.972
14.937
15.843
5.785
6.249
20.453
21.124
21.774
22.405
9.447
9.738
7.833
8.515
7.468
24.770
18.294
23.617
27.944
14.460
13.970
13.461
12.933
11.201
14.934
15.394
11
10.560
12.540
13.218
10.239
21.284
25.045
25.767
26.437
28.040
2.640
29.557
40.899
4.180
5.911
31.000
4.573
7.920
8.348
9.145
9.878
5.280
9.347
19.606
7.467
6.985
34.972
37.387
40.742
51.194
56.081
59.114
.806
in Millimeters
4.091
13.464
10.562
11.809
12.936
14.463
15.397
7.085
5.281
6.680
23.019
9.147
8.837
8.181
17.515
19.041
19.760
25.872
16.700
26.928
12.383
Suction
11.823
14.480
15.640
11.059
Lines
20.449
22.088
22.863
23.613
24.340
25.732
26.400
27.689
28.920
30.101
31
22.895
23.646
24.373
22.118
25.080
15.840
21.314
20.478
16.697
19.579
37.335
42.569
44.176
16.274
Lines
18.694
17.710
18.668
3.734
16.720
7.240
8.360
5.903
47.659
49.458
32.333
52.873
33.394
34.421
35.419
57.617
36.390
39.158
17.734
32.378
33.700
36.200
38.538
39.655
6.467
41.800
43.840
45.790
54.501
67.400
61
64.756
69.945
Pressure
Return
.237
.999
Recommended
Flow Diameter
340
320
380
360
LPM*
600
550
500
450
400
650
700
800
750
300
Flow Rate
Maximum
imum
Table U14 Millimeters
Recommended Flow Diameters, in
* LPM = Liters Per Minute
in Millimeters
30.793
29.874
74.774
72.400
Lines
45.726
32.554
61.913
59.032
40.906
42.577
44.184
35.426
102.389
106.570
88.671
45.735
47.235
114.474
118.228
28.925
31.686
Lines
Suction
Lines
79.310
77.075
50.090
48.679
47.226
Return
39.165
37.342
98.030
93.468
83.600
81
52.800
51.463
.483
110.592
64.667
67.307
69.848
56.003
72.299
74.670
Pressure
33.400
Recommended
Flow Diameter
Metric Tube Pressure Ratings
2.25
2.5
1.5
20.0128
10.0235
12.0201
13.0188
12.0282
14.0176
20.0282
13.0
15.0
12.0
17.0
10.0
11.0
3.0
2.0
2.5
3.5
4.0
1.0
1.5
4.0389
6.0333
5.0431
8.0282
7.0373
2.5
2.0
4.0
3.5
4.0549
4.0666
7.0495
6.0576
5.0651
8.0507
7.0676
9.0478
1.0
3.0658
6.0478
5.0576
8.0409
9.0434
6.0641
403
264
478
320
426
282
313
212
639
585
209
400
289
351
410
143
271
247
135
235
277
121
146
230
1
27
39
77
53
97
92
60 Steel
0.75
0.8
0.5
3.0432
3.0313
3.5376
4.5
409
256
366
465
301
386
2.0
11.0302
21.0226
16.0157
19.0192
19.0
16.0
14.0
18.0
3.0549
9.0353
3.0
2.0692
1.5
1.5
7
409
376
338
353
386
452
385
235
373
266
392
575
4
281
330
556
223
518
3
312
100
345
170
65
30
1.0
2.0522
2.5
333
Low-Carbon
Thick.
1.0.
1.4571
Tube
Wall
Steel
Stainless
St.
37-4
(mm)
Metric Tu bes
28
25
38
65
30
35
38
35
42
50
80
30
25
0.0.
(Bar) Tube
Desian(mm)
Pressure
Table U16 -
Metric Tube Pressure Ratings
25.0
24.0
17.0
16.0
15.0
4.5
5.0
2.0
1.5
4
394
201
282
151
37
78
209
319
353
386
117
271
153
177
22.0
26.0
31.0
29.0
32.0
33.0
18.0
4.0
6.0
403
242
419
223
297
161
186
34
124
351
330
339
142
219
28.0
36.0
34.0
7.0
371
390
446
269
134
315
268
360
104
247
10.0
8.0
60.0
437
3
53
256
25.0
235
376
Low-Carbon
Thick.
I.D.
1.4571
Steel
Tube
Wall
Stainless
S
teel
20.0
23.0
30.0
27.0
2.5
3.0
252
302
409
322
188
223
236
289
143
188
181
168
38.0
338
200
49.0
9.0
347
253
St.37-4
(mm)
Metric Tubes
Design Pressure (Bar)