Diagnosis and Solution for High-Speed Turboexpander Thrust...
Transcript of Diagnosis and Solution for High-Speed Turboexpander Thrust...
Diagnosis and Solution for High-Speed Turboexpander Thrust Loading IssueDiagnosis and Solution for High-Speed Turboexpander Thrust Loading Issue
Mohamed El-AbyoukiAbu Dhabi Gas Industries Ltd (GASCO) - Abu Dhabi, UAE
and
Armando GuerreroAtlas Copco Mafi-Trench Company LLC - California, USA
Mohamed ElMohamed El--AbyoukiAbyoukiAbu Dhabi Gas Industries Ltd (GASCO) Abu Dhabi Gas Industries Ltd (GASCO) -- Abu Dhabi, UAEAbu Dhabi, UAE
andand
Armando GuerreroArmando GuerreroAtlas Copco MafiAtlas Copco Mafi--Trench Company LLCTrench Company LLC -- California, USACalifornia, USA
11stst Middle East Turbomachinery SymposiumMiddle East Turbomachinery Symposium
RoadmapRoadmap
Background
Problem Identification
Analysis
Scope
Testing
Conclusions
BackgroundBackground
Problem IdentificationProblem Identification
AnalysisAnalysis
ScopeScope
TestingTesting
ConclusionsConclusions
Bab Turboexpander PlantBab Turboexpander Plant
Plant Visit 2007Plant Visit 2007
Plant Personnel described problem during vendor site visit in 2007
High Compressor Thrust
Thrust Balancer Full Open
Operation Limited
Plant Personnel described problem Plant Personnel described problem during vendor site visit in 2007during vendor site visit in 2007
High Compressor ThrustHigh Compressor Thrust
Thrust Balancer Full OpenThrust Balancer Full Open
Operation LimitedOperation Limited
History of Bab Plant TurboexpanderHistory of Bab Plant Turboexpander
1991 re-rate for higher capacityRe-rate not factory testedAt commissioning, high compressor thrust observedFlow bypassed to allow unit operation within thrust limits
1991 re1991 re--rate for higher rate for higher capacitycapacityReRe--rate not factory testedrate not factory testedAt commissioning, high At commissioning, high compressor thrust compressor thrust observedobservedFlow bypassed to allow Flow bypassed to allow unit operation within unit operation within thrust limitsthrust limits
Bab PlantBabBab PlantPlant
Turboexpander DataTurboexpander Data
Speed: Design Speed = 24,000 RPMPower: Rated = 1,595 kWPressure: Expander = 44 barg; 17 bargTemperature: Expander = -50.3 C; -83.9 CFlow: Expander = 105,674 Kg/HrGas Handled: Natural Gas = 17.5 Mol. Wt.Manufactured: 1979; re-rated in 1991
Speed: Speed: Design Speed = 24,000 RPMDesign Speed = 24,000 RPMPower: Power: Rated = 1,595 kWRated = 1,595 kWPressure: Pressure: Expander = 44 Expander = 44 bargbarg; 17 ; 17 bargbargTemperature: Temperature: Expander = Expander = --50.3 C; 50.3 C; --83.9 C83.9 CFlow: Flow: Expander = 105,674 Kg/HrExpander = 105,674 Kg/HrGas Handled: Gas Handled: Natural Gas = 17.5 Mol. Wt.Natural Gas = 17.5 Mol. Wt.Manufactured: Manufactured: 1979; re1979; re--rated in 1991rated in 1991
Turboexpander LayoutTurboexpander Layout
EXPANDER
COMPRESSOR
Automatic Thrust Balancer (ATB)Automatic Thrust Balancer (ATB)
Thrust Venting PortThrust Venting Port
IdealIdeal
CompressorExpander
ATB Fully ClosedATB Fully Open
Thrust Capacity
1991 Design Observed1991 Design Observed
CompressorExpander
2008 Upgrade (expected)2008 Upgrade (expected)
CompressorExpander
Scope of UpgradeScope of Upgrade
Evaluation of Most Economical SolutionEvaluation of Most Economical Solution
Consider New Expander Wheel and SealConsider New Compressor Wheel and SealConsider New Expander AND Compressor Wheels/Seals
Consider New Expander Wheel and SealConsider New Expander Wheel and SealConsider New Compressor Wheel and SealConsider New Compressor Wheel and SealConsider New Expander AND Compressor Consider New Expander AND Compressor Wheels/SealsWheels/Seals
New Compressor Wheel and SealNew Compressor Wheel and SealNew Compressor Wheel and Seal
New Compressor WheelNew Compressor Wheel
3D 3D bladingblading digitized from original cast wheeldigitized from original cast wheelSolid model created for analysisSolid model created for analysis
Reverse Engineering
CNC Milled from Solid ForgingCNC Milled from Solid Forging
New Compressor WheelNew Compressor Wheel
Larger Seal Area Larger Seal Area
New Compressor WheelNew Compressor Wheel
Old = 6.25 Inch Old = 6.25 Inch New = 8.0 Inch New = 8.0 Inch
Refurbished ATB AssemblyRefurbished ATB Assembly
Full Speed Factory TestFull Speed Factory Test
ResultsResults
Factory test confirmed successful modification
Turboexpander restarted in December 2008
Thrust levels reduced as predicted
Unit now capable of full speed operation
Factory test confirmed successful Factory test confirmed successful modificationmodification
Turboexpander restarted in December 2008Turboexpander restarted in December 2008
Thrust levels reduced as predictedThrust levels reduced as predicted
Unit now capable of full speed operationUnit now capable of full speed operation
ConclusionsConclusions
Old problems warrant periodic investigation
Large gains possible from small investments
Factory testing reduces risk on upgrades
Old problems warrant periodic investigationOld problems warrant periodic investigation
Large gains possible from small investmentsLarge gains possible from small investments
Factory testing reduces risk on upgradesFactory testing reduces risk on upgrades
Thank YouThank You