Engine Analyzer and Reliability Workshop July 27

Engine Analyzer and Reliability Workshop July 27

Engine Analyzer and Reliability Workshop
July 27-29, 2011
Nashville, Tennessee
Main Units
• Existing engine compressor base – primarily
reciprocating slow speed integrals
– 307 Recips
• 250 rpm
• 300 rpm
• 330 rpm
• 350 rpm
– 57 Gas turbines
– 04 Steam turbines
– 23 Electric motors
2
CAT/Ariel Installation
3
CAT/Ariel Unit Specifications
Engine:
Compressor:
•
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•
•
•
•
•
•
•
•
•
•
CAT G3616
V-16 Turbo-charged
Compression ratio: 9.2:1
Bore X Stroke: 11.8 x 11.8
Displacement: 20,704 cu.in.
Speed Range: 750 – 1000
rpm
• Continuous BHP:
4,735 @ 1,000 rpm
4,260 @ 900 rpm
3,790 @ 800 rpm
3,550 @ 750 rpm
Ariel JGZ-6
6 Throw
Two Stage
Stroke Diameter: 6.75-in
Rod diameter: 2.875-in
Cylinders:
– First Stage:
• Three 9.125-in
– Second Stage
• Three 5.875-in
• Clearance Volume Pockets
• Plate Valves
4
CAT/Ariel Compressor Layout
Photo Courtesy of ACI
5
6
Analyzer Performance
Acceptance Testing
7
Unit Load - Analyzer
8
Test Data - Analyzer
9
PV Curve Example - Analyzer
10
PV Curve Example - Analyzer
11
Predicted Unit Load - Modeling Software
12
Predicted PV Curves - Modeling Software
13
Unit Load Values - Comparison
Software
Model
Prediction
CAT
Percent
Load
Analyzer
Measured
98 %
107 %
76 %
Which Horsepower Is Correct?
14
How Do We Determine
Correct Horsepower
15
Review Of Horsepower Values
Predicted Model – calculated value
Analyzer based tuning
Known compressor geometry and parameters
Typically 2-3 percent less than actual
CAT % Load – calculated value
Based on fuel flow, BTU and engine speed
CAT calculated fuel flow matched station
custody transfer flow measurement
Typically 2-3 percent more than actual
Analyzer – measured value
Industry standard for determining actual load
16
Understanding The Unit Load Display
CAT Publication
Understanding The Engine Load Display That Is
A Part Of The Engine Supervisory System (ESS)
Media Number SEBD9307-00
Publication Courtesy of Caterpillar
17
CAT Percent Engine Load Accuracy
The accuracy of the displayed “Engine
Load” value will be dependent on the
following parameters:
Emission settings
Misfire
Fuel quality
Valve lash adjustments
Fuel correction factor
Pre-chamber tuning
18
Factors Which Affect Accurate Horsepower
Indicator
Valves
Mating of
Sensors &
Valves
Timing
Calibrated
Pressure
Sensors
Machine
Setup Data
Mechanical
Condition
Correct
Loading
Sequence
Accurate
Horsepower
Station
Operating
Conditions
19
Configuration
20
Timing
 No TDC indicator
provided
 Installed pointer on
Engine and verified
compressor timing
 Flexible shim pack
type coupling
 Separate TDC
indicators required for
engine and
compressor
21
Indicator Valves
Transco standard valve
– Anderson Greenwood
– ¼” diameter opening
Acceptable on slow
speed machines
Industry Standards
require ½” full open
valves on high speed
machines
22
TORQUE QUESTION
From: Baroni, Steven T
Sent: Wednesday, April 14, 2010 12:57 PM
To: Dixon, Noah H; Howerton, T Bruce
Cc: Gregorek, Kasia; Neubauer, William J; Sinclair, Ross M; Truxell,
Richard W
Subject: Torque on Unit #4 @ Station 77
Noah / Bruce,
Kasia and I noticed some higher than expected torque on Unit #4
this morning at Eminence and were wondering if we need to be
alarmed by this reading? I have attached a plot below that shows
the torque on the unit getting as high as 108% over the last couple
of days…
Thanks for looking into this for us.
23
TORQUE
24
25
Locate Compressor TDC-Ariel Procedure
 Move towards ODC
 Set dial indicator on crosshead to zero
reading when close to ODC
 Place mark on flywheel or hub
 Note maximum reading at TDC
 Continue moving past ODC and stop when dial
indicator reading matches starting point
 Place mark on flywheel or hub
 Carefully split the difference between marks
 This should be the TDC mark
 Recheck…Recheck…Recheck!!!
26
Compressor Timing
Compressor timing checked and verified at least
four times during this process
27
Typical Transco Sensor Assembly
28
Typical Transco Indicator Valve
Anderson Greenwood rising
stem plug valve with a ¼
inch straight though port
Standard valve used on
all slow speed
compressors
29
New Quadrant Valve
Worked with Kiene Diesel
to locate this valve
Difficult locating full
opening ½ inch valve for
high pressure and
temperature applications
30
Photo Courtesy of Kiene Diesel
31
Photo Courtesy of Kiene Diesel
32
Indicator Valve Comparison
21 % IHP Difference
Anderson Greenwood
¼-inch Transco Valve
New Full Opening
½-inch Ball Valve
33
Typical Transco Indicator Valves
Anderson Greenwood
¼” Transco Valve
34
Sensor Installation Comparison
3 % IHP Difference
Blue - Sensor installed directly on valve
Red - Transco standard monitoring assembly
35
Load/Percent Load Comparisons
Typical Valve
Meas. HP
Valve Test
Meas. HP
After Test
Proj. HP
1H
1C
2H
2C
3H
3C
4H
4C
5H
5C
6H
6C
110
350
198
312
119
352
423
307
109
336
420
301
3337
123
340
297
358
216
433
423
269
112
330
512
351
3764
216
433
297
358
216
433
512
351
216
433
512
351
4328
% Load
76
84
96
Cyl End
Pred. HP
CAT % Load
After Test Projected BHP
Used BHP from like
configured cylinders to
project the BHP on
cylinders which still had
the “Typical” Transco
indicator valves installed
BLUE > ¼ inch dia valves
RED > ½ inch dia valves
98
107
36
Conclusions
 Verified timing was not a problem - less than a
degree difference between the engine indicator
and compressor indicator mark
 Verify the valve/sensor combination has no
significant influence on the measured pressure
waveforms
 Restrictive valve causes pressure waveform to be
filtered and delayed, causing lowered IHP and
flow measurements
 Large volume in sensor assembly had little
influence on IHP
37
38
New Compressor Station Installation
Need For On-Line “CPM” System
39
Background
Test Objective:
Compare IHP values of various sensor
and indicator valve combinations
 Tests were conducted on January 19, 2011 on a
KB-Z 6-throw compressor
 Test conducted on the crank ends of the
compressor because:
 no unloaders or pockets installed on these ends
all cylinders are identical
 Theoretical curve based on Ariel’s published crank
end clearance of 46.11%
40
Various Configurations
41
Kiene SMCV – 10 – 5 Valve
inch passage
Photo Courtesy of Kiene Diesel
42
Kiene SMCV – 10 – 5 Valve
Blue - ½” NPT sensor on side port
Red - ½” NPT sensor on end port
43
Kiene Valve Conclusions
 Very little difference between test points
 Possibly faster expansion using side mounted
sensor
 Provided most compact mounting configuration
 Allowed convenient portable sensor attachment
44
Swagelok SS-5PDGM8-F8 Valve
½ inch NPT
¼ inch opening plug
45
Swagelok SS-5PDGM8-F8 Valve
Blue - ½ inch NPT side port
Red - ½ inch NPT end port
46
Swagelok Valve Conclusions
 Side port has slow expansion
 End port preferable for permanent sensor
mounting
 Would protrude out too far, possibly causing
operations issues
47
Anderson Greenwood H7V1S44Q Valve
½ inch NPT
¼ inch opening plug
48
Anderson Greenwood H7V1S44Q Valve
11 % IHP Difference
Blue - ½” NPT sensor directly on valve
Red - Transco standard monitoring assembly
49
Anderson Greenwood Valve Conclusions
 Transco assembly resulted in:
 slower compression and expansion
11 % lower IHP
50
Data Comparison
Test 1
Test 2
Test 3
Configuration
Acceptable
Kiene Valve Side Port
√
Kiene Valve End Port
√
Swagelok Valve Side Port
Swagelok Valve End Port
√
AG Valve Direct Mount
√
AG Valve "Transco" Mount
PV
Line 1
Line 2
Line 1
Line 2
Line 1
Line 2
IHP
286.95
286.86
282.14
289.02
282.60
255.25
% Clearance
Set
Calc
46.0
49.8
46.0
52.1
46.0
62.5
46.0
50.0
46.0
50.0
46.0
76.0
We Have A Winner!
51
Photo Courtesy of Kiene Diesel
52
Conclusions
 Tests show it is very important to verify the
valve/sensor combination has no significant
influence on measured pressure waveforms
 Valve design plays a vital role
port diameter
flow pattern
volume after port
Best agreement with ideal PV curve was obtained
with Kiene valve utilizing side mounted ½ inch
NPT port
53
Conclusions
 Restrictive valve followed by large volume causes
pressure waveform to be filtered and delayed,
causing lowered IHP and flow measurements on
High Speed Machines
54
Sometimes Compressor Analysis
May Appear As An Illusion
55
Questions
56