Centrifugal Compressor Spiral Dry Gas Seal Simulation Working at Reverse Rotation

2010 ◽

Cited By ~ 2

Author(s):

Weimin Wang ◽

Jinji Gao ◽

Yan Li ◽

Shuangxi Li

Keyword(s):

Experimental Study ◽

Centrifugal Compressor ◽

Thrust Bearing ◽

Mechanical Performance ◽

High Reliability ◽

Relevant Information ◽

Axial Displacement ◽

Oil Film ◽

Dry Gas Seal ◽

Low Leakage

For centrifugal compressor, discharge or suction pressure variations due to process fluctuations or balance drum seal degradation can result in rotor thrust increasing which may jeopardize thrust bearing and compressor’s reliability. Also, the leakage flow through balance drum seal can seriously affect the efficiency of compressor. Summarizing the characteristic of axial displacement fault about centrifugal compressor and analyzing the mechanical performance of tilt pads thrust bearing, theory of axial displacement fault self-recovery is presented and realized through experimental study. The method presented in this paper monitors the stiffness of oil film and identifies the reason of axial displacement increasing. Also the low leakage feature of Dry-Gas-Seal (DGS), high reliability of labyrinth, and the feasibility of upgrading existing structure are taken into account at the same time to design a combined labyrinth-dry gas seal system on the balancing drum. Based on the combined seal system, a Fault Self-Recovering (FSR) mechanism for the fault of rotor axial displacement is introduced to assure the minimum oil film thickness was ensured in real time. The modern Computational Fluid Dynamics (CFD) and experimental study were used to validate this concept. The result and relevant information indicate that the method can realize axial displacement fault self-recovering effectively and the combined sealing system could improve the efficiency of the centrifugal compressor about four percent.

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Measurements of End Cap Temperatures in a Multistage Barrel-Style Centrifugal Compressor

Volume 9: Oil and Gas Applications; Supercritical CO2 Power Cycles; Wind Energy ◽

10.1115/gt2019-91798 ◽

2019 ◽

Author(s):

Natalie R. Smith ◽

Jason C. Wilkes ◽

Jonathan Wade ◽

Timothy C. Allison ◽

Meera Day Towler ◽

...

Keyword(s):

Centrifugal Compressor ◽

Temperature Limit ◽

Detailed Understanding ◽

Dry Gas Seal ◽

Thermal Distribution ◽

Discharge Temperature ◽

Gas Seals ◽

Process Fluid ◽

Set Up ◽

Gas Supply

Abstract Gas compressor customers desire to operate gas compressors at higher discharge temperatures. In barrel-style centrifugal compressors, dry gas seals are used to limit the leakage along the shaft from the process fluid to atmosphere. The temperature limit of dynamic O-ring seals in the dry gas seal cartridge is one of the primary limiters to operating gas compressors at higher discharge temperatures. While the present discharge temperature limit is conservative compared to the seal limits, without a detailed understanding of the thermal distribution around the discharge-side end cap, operation at compressor discharge temperatures that exceed seal limits has too much risk. Thus, this paper describes the approach taken to characterize the temperatures around the discharge end dry gas seal of a commercial C335EL centrifugal compressor. A phased test matrix with increasing discharge temperatures was conducted so that the temperature distribution throughout the end cap could be assessed. The full-scale, highly-instrumented compressor was operated at discharge pressures and temperatures ranging from 4.7 to 9.4 MPa (680 to 1370 psi) and 113 to 218 degree Celsius (235 to 425 degrees Fahrenheit), respectively. The experimental test set-up and results are presented herein. Results include demonstration of successful compressor operation at discharge temperatures greater than seal limits as well as the end cap temperature sensitivity to lube oil supply and dry gas supply temperatures.

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Case Study - Dry Gas Seal Boosters’ Failure and Impact on Centrifugal Compressor Auxiliary System

10.2118/188735-ms ◽

2017 ◽

Author(s):

Arumugampillai Manikandan ◽

Anwer Zeeshan

Keyword(s):

Centrifugal Compressor ◽

Auxiliary System ◽

Dry Gas Seal

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The Liquid Condensation Conditions in the Dry Gas Seal System

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.752-753.199 ◽

2015 ◽

Vol 752-753 ◽

pp. 199-204

Author(s):

Ai Lin Ma ◽

Peng Yun Song

Keyword(s):

Centrifugal Compressor ◽

High Speed ◽

Dew Point ◽

Gas Flows ◽

Thomson Effect ◽

Adiabatic Expansion ◽

Gas Temperature ◽

Liquid Equilibrium ◽

Vapor Liquid Equilibrium ◽

Dry Gas Seal

Dry gas seal is often used as the seal devices in centrifugal compressor and other high-speed rotating equipment, which requires seal gas clean and dry. If there is some liquid in the seal gas, the dry gas seal will rapidly fail. When the seal gas flows through the filters, valves, orifices, seal faces and so on, the gas temperature will decrease resulted from the Joule- Thomson effect. If the gas temperature is lower than the corresponding dew point, there will be liquid condensation in dry gas seal system. Wet air is taken as an example to show how to calculate the pressure and temperature relationship when it is adiabatic expansion. Dew point lines at different conditions are calculated by considering the vapor-liquid equilibrium. Liquid condensation conditions are acquired by comparing expansion lines and dew point lines, and the factors of influencing liquid condensation were analyzed. The results shows that decreasing gas humidity, increasing the gas temperature can effectively reduce the liquid condensation.

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