hi, we have Alstom steam turbine and the hydraulic power for CV and Stop valve is provided by a set of hydraulic pumps, via a trip block.
When the machine trips or shutdown the logic does not stop the hydraulic pump automatically and it should be manually stopped. My question is, what might be the reason that Alstom kept the pump running after trip or shutdown. infact, there is no auto-stop command for hydraulic pumps and only time they are stop in auto is when there is fire detection signal.
I checked with other stations using different manufacturers and in almost all of them, the hydraulic pump is left running after trip.
I recall similar logic with Ansaldo/Siemens ST, where automatic sequence doesn't stop the hydraulic pumps after trip and normal shutdown.
When the machine trips or shutdown the logic does not stop the hydraulic pump automatically and it should be manually stopped. My question is, what might be the reason that Alstom kept the pump running after trip or shutdown. infact, there is no auto-stop command for hydraulic pumps and only time they are stop in auto is when there is fire detection signal.
I checked with other stations using different manufacturers and in almost all of them, the hydraulic pump is left running after trip.
I recall similar logic with Ansaldo/Siemens ST, where automatic sequence doesn't stop the hydraulic pumps after trip and normal shutdown.