What did GE's analytics software find?
On September 28, the GE SmartSignal solution detected a falling pressure ratio on the first stage of a reciprocating compressor. The suction pressure increased to values as high as 80 psi, while the model estimate remained at 52 psi. The discharge pressure decreased to 119 psi, with a model prediction of 132 psi. GE’s Industrial Performance & Reliability Center (IPRC) added these items to the weekly report for discussion with the customer.
What was the underlying cause?
Upon investigation, the customer found cracks in the suction and discharge pressure valves on the first stage of the reciprocating compressor. Several transmitters also were deemed to be faulty and subsequently were replaced.
What was the value to the customer?
After making the necessary repairs, the IPRC was able to help the customer confirm that the maintenance actions were successful by showing that the actual pressure ratio returned to the model predicted value. Continued operation with the cracked valves would have severely reduced the operating efficiency of the compressor. The early notification from the IPRC allowed the customer to plan maintenance while not affecting day-to-day operation of the plant, thus saving unnecessary downtime.
Suction pressure slowly increased from 54 psi to 75 psi before shutting down on Oct 15 to make valve replacements. Suction pressure continued to rise to as high as 84 psi before shutting down again on Oct 21 to replace the pressure transmitter. Upon restart, suction pressure returned to normal.