149625020 Instrumentation Bently Nevada
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Reciprocating Compressor Cylinder Pressure Patterns Bently Nevada™ Asset Condition Monitoring GE Measurement & Control For more information visit www.bentlyrecip.com or www.bntechsupport.com or call (775) 215-1818 Bently Nevada, Keyphasor and System 1 are trademarks of General Electric Company. Copyright © 2012 General Electric Company. All rights reserved. Packing Vent Temperature Packing Case Temperature Rod Position Cylinder Pressure Cylinder Acceleration Suction Temperature Cylinder Valve Temperature Multi-Event Keyphasor® System Main Bearing Temperature Frame Vibration Connecting Rod Bearing Temperature Crosshead Vibration Single-Event Keyphasor® System Instrumentation Layout Components and Nomenclature Connecting Rod Multi-Event Wheel Timing Details Isolation Valve (should not induce channel resonance reference GER-4273) Mechanical Bracing To Protect Cylinder Pressure Transducer Cylinder Pressure Transducer (-/+ 0.5% accuracy for 1+ billion cycles) Leak to Low Pressure Side (often suction valves) Leak to High Pressure Side (discharge valves) Inter-Chamber Leak (usually piston rings) Red is Theoretical Pressure Curve Black is Indicated Pressure Curve Leak to Low Pressure Reservoir (crank end shown, head end similar) Leak from High Pressure Reservoir (crank end shown, head end similar) Red is Theoretical Pressure Curve Black is Indicated Pressure Curve Supporting Evidence • Is flow balance greater than 1.05? • Does the trend of a particular suction valve temperature indicate a rise compared to the other suction valve covers? • Does valve cover acceleration/ultrasonic show high amplitude when suction valves ar e closed? Supporting Evidence • Is flow balance less than 0.95? • Does the trend of a discharge valve temperature indicate a rise compared to the other discharge valve covers? • Does valve cover acceleration/ultrasonic show high amplitude when discharge vavles are closed? Red is Crank End Theoretical Pressure Curve Black is Crank End Indicated Pressure Curve Inter-Chamber Leak Supporting Evidence • Is flow balance on both chambers greater than 1.05? • Is discharge temperature elevated compared to adiabatic discharge temperature? • Does acceleration/ultrasonic show high amplitudes when chamber pressures different and low amplitudes when chamber pressures are equal? Pressure Versus Volume Log Pressure Versus Log Volume Pressure Versus Volume Log Pressure Versus Log Volume Pressure Versus Volume Log Pressure Versus Log Volume Indicated pressure crosses theoretical pressure (both chambers) Cylinder Pressure Installation Details 1. Drill and tap three 3/8-24 UNF 2B thread 1.00 in. deep 120 degrees apart on 3.00-inch diameter bolt circle. 1 2 3 1. Direction of rotation 2. Falling edge 3. Divided notch 4. Trailing narrow notch 1 2 1. Direction of rotation 2. Minimum negative voltage output 1 2 1. Direction of rotation 2. Maximum negative output voltage 1 2 1. Direction of rotation 2. Keyphasor output equals halfway value 38.1 mm (1.500 in.) radius 120° 120° 3/8-24 UNF 2B 25.4mm (1.00 in.) deep 3 places 2. Install the guiding stud of the recip multi-event wheel. 3. Slide the recip multi-event wheel over the guiding stud and align the falling edge of the divided notch with the Keyphasor. The second narrow notch should trail the first one in the direction of rotation. Loosely install 3/8 – 24 bolts to hold the wheel in place. 4 Recip Multi-Event Wheel (Part No. 145732-01) Recip Multi-Event Stud and Pilot (Part No. 146622-01) Recip Mulit-Event Wheel Kit (Part No. 146973-01) 4. You can precisely align the edge by measuring the voltage from the Keyphasor probe-proximitor combination when the probe is located over the notch, and then when it is over the protrusion. Rotate the wheel to obtain the minimum negative Keyphasor voltage over the protrusion and record this value. 5. Rotate the wheel to obtain the maximum negative Keyphasor voltage over the notch and record this value. Average the two voltage values to get the precise edge value. 6. Rotate the wheel back to the edge. When the Keyphasor output equals the calculated halfway value, secure the wheel into place Maximum Allowable Continuous Combined Rod Load (MACCRL) A value determined by the Original Equipment Manufacturer (OEM) based on design limits of the various components in the compressor frame and the running gear (bearings, crankshaft, connecting rod, crosshead assembly, zpiston rod, piston assembly). Maximum Allowable Continuous Gas Load (MACGL) A value determined by the OEM based on the design limits of the static components (frame, distance piece, cylinder, and bolting). Rod Reversal The shortest distance, measured in degrees of crank revolution, between each change in sign of force in the combined rod-loading curve. Gas Force Synch Crank Angle Compressor Train From 29APR2003 12:36:39 To 29APR2003 12:36:39 Historical MACHINE SPEED: 276 rpm Inertial Load Crank Angle Compressor Train Historical Combined Force Crank Angle Compressor Train Historical -100 -50 0 50 100 0 100 200 300 10k lbf/div 20 Degrees/div Crank Angle <--COMPRESSION FORCE TENSION--> TDC 0 Degrees -105746.2 lbf (-470382.5 N) 0 Degrees 43951.9 lbf (195508 N) 0 Degrees -61794.3 lbf (-274875 N) 10k N/div <--COMPRESSION FORCE TENSION--> 0 -220 -440 440 220 Rod Reversal Green is Head End Theoretical Pressure Curve Blue is Head End Indicated Pressure Curve 5 %/div Displaced Volume INDICATED PRESSURE TDC Indicated Suction Pressure (Toe Pressure) Cylinder pressure when the piston is at bottom-dead-center for head-end chamber or at top-dead-center for crank-end chamber. Indicated Discharge Pressure (Heel Pressure) Cylinder pressure when the piston is at top-dead-center for head-end chamber or at bottom-dead-center for crank-end chamber. Compression Ratio Indicated discharge pressure divided by the indicated suction pressure. Indicated Suction Pressure Indicated Discharge Pressure Minimum Pressure Smallest indicated pressure value that occurs over the entire pressure-volume cycle. Maximum Pressure Largest indicated pressure value that occurs over the entire pressure-volume curve cycle. Maximum Pressure Minimum Pressure Reciprocating Compressor Operating Cycle Indicated pressure compression and expansion strokes not parallel in log-log format. Indicated pressure rises faster than theoretical on compression stroke. Indicated pressure falls slower than theoretical on expansion stroke (if theoretical curve uses cylinder nameplate clearance). Indicated pressure rises slower than theoretical on compression stroke. Indicated pressure compression and expansion strokes not parallel in log-log format. Rounded Toe Indicated pressure falls faster than theoretical on expansion stroke (if theoretical curve uses cylinder nameplate clearance). Rounded Heel Crosshead Crosshead Pin Bushing Lubricating Passage Crosshead Pin Connecting Rod Piston Rod Cooling Water Suction Valve Cage Discharge Valve Pressure Packing Case Chamber (Frame End or Crank End) Crosshead Pin Discharge Valve Cage Valve Cover Cylinder Head (Outer End or Head End) Wear Bands (Rider Rings) Cylinder Piston Piston Rings Suction Valve Chamber (Outer End or Head End) Cylinder Head (Frame End or Crank End) Distance Piece Intermediate Partition Packing Oil Wiper Packing Piston Rod Locknut Crankpin Bearings Main Bearings Crankshaft Frame Crosshead Shoe Crosshead Assembly Nomenclature Discharge Temperature API-618 (Fifth Ed.) Protection Solution Management Solution Channel Resonance on Pressure Versus Displaced Volume Curve Pressure Operated Valves Mechanically Operated Valves Typical Pressure Versus Displaced Volume A A A A typical indicated cylinder pressure curve will have some pressure fluctuation when the suction and discharge valves are opened. The areas labelled “A” and indicated by braces show these pressure fluctuations. When the valves are closed, the pressure shows a smooth line. A pressure transducer installation suffering from channel resonance will show pressure fluctuations when the suction and discharge valves are closed as well as when the valves are opened. The frequency of this resonance remains nominally constant throughout the cycle. 1 2 P2 P1 PRESSURE VOLUME Stroke CLEARANCE VOLUME OUTLET INLET 1 2 3 P2 P1 PRESSURE VOLUME Stroke CLEARANCE VOLUME OUTLET INLET 1 2 3 4 P2 P1 PRESSURE VOLUME Stroke CLEARANCE VOLUME OUTLET INLET 1 2 3 4 5 P2 P1 PRESSURE VOLUME Stroke CLEARANCE VOLUME OUTLET INLET 1 2 3 4 5 P2 P1 PRESSURE VOLUME Stroke CLEARANCE VOLUME OUTLET INLET ™
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Transcript of 149625020 Instrumentation Bently Nevada
Reciprocating Compressor Cylinder Pressure Patterns Bently Nevada™Asset Condition Monitoring
GE Measurement & Control
For more information visit www.bentlyrecip.com or www.bntechsupport.com or call (775) 215-1818 Bently Nevada, Keyphasor and System 1 are trademarks of General Electric Company.Copyright © 2012 General Electric Company. All rights reserved.
Packing VentTemperature
Packing CaseTemperature
Rod Position
CylinderPressure
CylinderAcceleration
SuctionTemperature
Cylinder ValveTemperature
Multi-EventKeyphasor®
System
Main BearingTemperature
FrameVibration
Connecting RodBearing
Temperature
CrossheadVibration
Single-EventKeyphasor®
System
Instrumentation LayoutComponents and Nomenclature
Connecting Rod
Multi-Event WheelTiming Details
Isolation Valve(should not inducechannel resonancereference GER-4273)
Mechanical BracingTo Protect CylinderPressure Transducer
Cylinder PressureTransducer(-/+ 0.5% accuracyfor 1+ billion cycles)
Leak to Low Pressure Side(often suction valves)
Leak to High Pressure Side(discharge valves)
Inter-Chamber Leak(usually piston rings)
Red is Theoretical Pressure CurveBlack is Indicated Pressure Curve
Leak to Low Pressure Reservoir(crank end shown, head end similar)
Leak from High Pressure Reservoir(crank end shown, head end similar)
Red is Theoretical Pressure CurveBlack is Indicated Pressure Curve
Supporting Evidence
• Is flow balance greater than 1.05?• Does the trend of a particular suction valve temperature indicate a rise compared to the other suction valve covers?• Does valve cover acceleration/ultrasonic show high amplitude when suction valves are closed?
Supporting Evidence
• Is flow balance less than 0.95?• Does the trend of a discharge valve temperature indicate a rise compared to the other discharge valve covers?• Does valve cover acceleration/ultrasonic show high amplitude when discharge vavles are closed?
Red is Crank End Theoretical Pressure CurveBlack is Crank End Indicated Pressure Curve
Inter-Chamber Leak
Supporting Evidence
• Is flow balance on both chambers greater than 1.05?• Is discharge temperature elevated compared to adiabatic discharge temperature?• Does acceleration/ultrasonic show high amplitudes when chamber pressures different and low amplitudes when chamber pressures are equal?
Pressure Versus Volume Log Pressure Versus Log Volume Pressure Versus Volume Log Pressure Versus Log Volume Pressure Versus Volume Log Pressure Versus Log Volume
Indicated pressurecrosses theoretical pressure
(both chambers)
Cylinder PressureInstallation Details
1. Drill and tap three 3/8-24 UNF 2B thread 1.00 in. deep 120 degrees apart on 3.00-inch diameter bolt circle.
1
23
1. Direction of rotation 2. Falling edge 3. Divided notch 4. Trailing narrow notch
1
2
1. Direction of rotation 2. Minimum negative voltage output
1
2
1. Direction of rotation 2. Maximum negative output voltage
1
2
1. Direction of rotation
2. Keyphasor output equals halfway value
38.1 mm (1.500 in.)radius
120° 120°
3/8-24 UNF 2B 25.4mm (1.00 in.) deep3 places
2. Install the guiding stud of the recip multi-event wheel.
3. Slide the recip multi-event wheel over the guiding stud and align the falling edge of the divided notch with the Keyphasor. The second narrow notch should trail the first one in the direction of rotation. Loosely install 3/8 – 24 bolts to hold the wheel in place.
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Recip Multi-Event Wheel(Part No. 145732-01)
Recip Multi-Event Stud and Pilot(Part No. 146622-01)
Recip Mulit-Event Wheel Kit(Part No. 146973-01)
4. You can precisely align the edge by measuring the voltage from the Keyphasor probe-proximitor combination when the probe is located over the notch, and then when it is over the protrusion. Rotate the wheel to obtain the minimum negative Keyphasor voltage over the protrusion and record this value.
5. Rotate the wheel to obtain the maximum negative Keyphasor voltage over the notch and record this value. Average the two voltage values to get the precise edge value.
6. Rotate the wheel back to the edge. When the Keyphasor output equals the calculated halfway value, secure the wheel into place
Maximum Allowable Continuous Combined Rod Load (MACCRL) A value determined by the Original Equipment Manufacturer (OEM) based ondesign limits of the various components in the compressor frame and the running gear (bearings, crankshaft, connecting rod, crosshead assembly, zpiston rod, piston assembly).
Maximum Allowable Continuous Gas Load (MACGL) A value determined by the OEM based on the design limits of the static components (frame, distance piece, cylinder, and bolting).
Rod Reversal
The shortest distance, measured in degrees of crank revolution, between each change in sign of force in the combined rod-loading curve.
Gas Force SynchCrank AngleCompressor Train From 29APR2003 12:36:39 To 29APR2003 12:36:39 Historical MACHINE SPEED: 276 rpmInertial LoadCrank AngleCompressor Train HistoricalCombined ForceCrank AngleCompressor Train Historical
-100
-50
0
50
100
0 100 200 300
10k
lbf/
div
20 Degrees/divCrank Angle
<--C
OM
PRES
SIO
N
FO
RCE
TE
NSI
ON
-->
TDC
0 Degrees -105746.2 lbf (-470382.5 N)
0 Degrees 43951.9 lbf (195508 N)
0 Degrees -61794.3 lbf (-274875 N)
10k
N/d
iv<-
-CO
MPR
ESSI
ON
F
ORC
E
TEN
SIO
N--
>
0
-220
-440
440
220
Rod Reversal
Green is Head End Theoretical Pressure CurveBlue is Head End Indicated Pressure Curve
5 %/divDisplaced Volume
IND
ICA
TED
PRE
SSU
RE
TDCIndicated Suction Pressure (Toe Pressure) Cylinder pressure when the piston is at bottom-dead-center for head-end chamber or at top-dead-center for crank-end chamber.
Indicated Discharge Pressure (Heel Pressure) Cylinder pressure when the piston is at top-dead-center for head-end chamber or at bottom-dead-center for crank-end chamber.
Compression Ratio
Indicated discharge pressure divided by the indicated suction pressure.
Indicated Suction Pressure
IndicatedDischarge Pressure
Minimum Pressure Smallest indicated pressure value that occurs over the entirepressure-volume cycle.
Maximum Pressure
Largest indicated pressure value that occurs over the entirepressure-volume curve cycle.
MaximumPressure
MinimumPressure
Reciprocating CompressorOperating Cycle
Indicated pressure compressionand expansion strokes not parallel in log-log format.
Indicated pressure risesfaster than theoreticalon compression stroke.
Indicated pressure fallsslower than theoretical
on expansion stroke(if theoretical curve
uses cylinder nameplate clearance).
Indicated pressure risesslower than theoreticalon compression stroke.
Indicated pressure compressionand expansion strokes not parallel in log-log format.
Rounded Toe
Indicated pressure falls faster than theoretical on expansion
stroke (if theoretical curveuses cylinder nameplate clearance).
Rounded Heel
Crosshead
Crosshead Pin Bushing
LubricatingPassage
CrossheadPin
ConnectingRod
Piston Rod
Cooling Water
Suction Valve Cage
Discharge Valve
Pressure Packing Case
Chamber (Frame End or Crank End)
Crosshead Pin
Discharge Valve Cage
Valve Cover
Cylinder Head(Outer End or
Head End)
Wear Bands (Rider Rings)
Cylinder
PistonPiston Rings
Suction Valve
Chamber (Outer End or Head End)
Cylinder Head (Frame End or Crank End)
Distance PieceIntermediate Partition Packing
Oil Wiper Packing
Piston Rod Locknut
Crankpin Bearings
Main Bearings
Crankshaft
Frame
CrossheadShoe
Crosshead AssemblyNomenclature
DischargeTemperature
API-618 (Fifth Ed.)
Protection Solution
Management Solution
Channel Resonance on Pressure Versus Displaced Volume Curve
Pressure Operated Valves Mechanically Operated Valves
Typical Pressure Versus Displaced Volume
AA
A
A typical indicated cylinderpressure curve will have somepressure fluctuation when thesuction and discharge valvesare opened. The areas labelled“A” and indicated by bracesshow these pressurefluctuations. When the valvesare closed, the pressure showsa smooth line.
A pressure transducer installation suffering from channel resonance will showpressure fluctuations whenthe suction and dischargevalves are closed as well aswhen the valves are opened. The frequency of this resonanceremains nominally constant throughout the cycle.
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P2
P1
PRES
SURE
VOLUME
Stroke
CLE
ARAN
CE
VOLU
ME
OUTLET
INLET
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3P2
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INLET
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SURE
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P1
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P2
P1
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VOLUME
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CE
VOLU
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OUTLET
INLET
™
