by admin-last modified 2008-10-29 /> Announcment: RoMaDyn SM Prensentation When: November 20, 2008

Please come and welcome our November speaker Richard Thomas, P.E. with RoMaDyn SM

The syn gas compressor train at an ammonia plant in northeast Pakistan consists of a Steam Turbine driving three barrel compressors; i.e. the Low Pressure (LP) Compressor, the Intermediate Pressure (IP) Compressor, and the High Pressure / Recycle (HP) Compressor. Dating back to the summer of 2001, the IP Compressor had experienced intermittent, cyclical vibration amplitudes in excess of 3 mil pp. In 2001, the coupling between the Steam Turbine and the IP Compressor was upgraded from the original, lubricated, gear type coupling to a non-lubricated, disk pack coupling. In 2001 and 2002 the IP Compressor was overhauled by the OEM on site. Additionally, the coupling between the Steam Turbine and IP Compressor was field balanced by plant personnel. However, after both of these outages and subsequent startup of the syn gas compressor train, the intermittent, cyclical vibration was still present in the IP Compressor.

In 2004 and May 2006 plant personnel engaged the services of other outside consultants at which time the bearings and seals were inspected and the Steam Turbine / IP Compressor coupling was again field balanced by plant personnel. After the startup of the syn gas compressor train after the May 2006 outage, the intermittent, cyclical vibration was still present in the IP Compressor.

1. Construct a combined rotor model of the Steam Turbine and the IP Compressor rotors in order to evaluate the affect of changing from the gear type coupling to a disc pack coupling.
2. Acquire and analyze pre-outage vibration response and process data (steady state, shutdown, and startup) in order to identify root cause for the sinusoidal vibration.
3. Consult on the disassembly and inspection of the IP Compressor bearing and oil seal assemblies.
4. Determine root cause for the intermittent, cyclical vibration occurring in the IP Compressor.
5. From the rotor model evaluate the allowable Steam Turbine / IP Compressor coupling unbalance in order to keep the vibration amplitude at the coupling below 1 mil pp.
6. Document the post outage results in a formal report and presentation to executive management.

This presentation discusses the results of this project.

Richard Thomas, P.E.

Richard has held the position of Manager Global Services for RoMaDynSM Corporation in Minden, NV since January 2003

Prior to his current position, his work experience included 11 years as a rotating equipment engineer in the petrochemical industry and 17 years in the Engineering Services Department of Bently Nevada Corporation where he held various field and management positions. Richard received his Bachelor of Science degree in Mechanical Engineering from Louisiana Tech University in 1975 and is registered as a Professional Engineer in the states of Nevada and Louisiana. He has published several papers relating to machinery diagnostics and machinery management. He is a member of ASME, as well as Tau Beta Pi and Pi Tau Sigma Engineering Honor Societies.