RESOLUTION OF A COMPRESSOR VALVE FAILURE: A CASE STUDY
Dresser-Rand, Painted Post, NY, USA
The commissioning date of three critical path ethylene compressors at a Belgian chemical plant was in jeopardy because the original
compressor valves failed within hours of start-up on the final stage of compression. The valve supplier attempted to resolve the
failures twice, without success. The failed concentric ring valve design was evaluated by the compressor OEM and determined to
have marginal reliability characteristics. A different type of compressor valve, the ported plate valve, was proposed as a potential
solution. Although a slight decrease in compressor efficiency was expected with the alternative valve technology, the client deemed
this an acceptable compromise to meet his production schedule. The new valves were installed in April 1999 and continue to run
Valve problems are reported as the primary reason for reciprocating compressor shutdowns. The anecdotal evidence is confirmed
by a recent survey of hydrogen compressors, which finds that 36% of unscheduled downtime is due to valve failures.
Compressor valves fail for a variety of reasons, which can generally be divided into design factors and operational factors. Design
factors include application and selection errors. Operational factors are related to the process gas conditions and to how the
compressor is run and maintained.
Discovering root causes of failure depends on a full exchange of information between the valve manufacturer and his client. The
client must be willing to provide complete operational data and the valve manufacturer must be willing to review and modify his valve
design. Since each reciprocating compressor is unique in the way it is operated and serviced, the circumstances surrounding each
case of valve failure and its resolution are also unique.
This case study illustrates how a valve failure can be attributed both to valve design considerations and to opera