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We have at power plant 16 units (GE 7E). Sometimes we faced problem in hydraulic system in some unit (4 or 5 units) such as:
- gas hydraulic pressure low
- Gas fuel hydraulic pressure low
- 88 HQ running
During annual maintenance we did the following inspections:
1- main hydraulic
2- replace main hydraulic coupling
3- auxiliary hydraulic pump (88HQ)
4- 88HQ motor and breaker
5- relief valves for main and auxiliary hydraulic pump
6- hydraulic filters
7- 20FG solenoid
8- 63HG1 -63HG2
9- oil leak inside pipes (lube oil tank)
10- check valves for main and auxiliary hydraulic pump
After annual maintenance we start the unit. At full speed no load 3600 RPM, we adjust hydraulic at 1500 PSI to make sure the main hydraulic pump work Correctly, give the desired hydraulic pressure, and be the auxiliary hydraulic pump standby. We succeeded in some units.
After one or two months later, the auxiliary hydraulic pump running again! And some units tripped by Gas fuel hydraulic pressure low or 88HQ overload!
Note: accumulator did not work 10 years ago. But strange in this subject, some units of the same frame work without problems for six consecutive months (peak season)
Note: type of fuel, Gas
- gas hydraulic pressure low
- Gas fuel hydraulic pressure low
- 88 HQ running
During annual maintenance we did the following inspections:
1- main hydraulic
2- replace main hydraulic coupling
3- auxiliary hydraulic pump (88HQ)
4- 88HQ motor and breaker
5- relief valves for main and auxiliary hydraulic pump
6- hydraulic filters
7- 20FG solenoid
8- 63HG1 -63HG2
9- oil leak inside pipes (lube oil tank)
10- check valves for main and auxiliary hydraulic pump
After annual maintenance we start the unit. At full speed no load 3600 RPM, we adjust hydraulic at 1500 PSI to make sure the main hydraulic pump work Correctly, give the desired hydraulic pressure, and be the auxiliary hydraulic pump standby. We succeeded in some units.
After one or two months later, the auxiliary hydraulic pump running again! And some units tripped by Gas fuel hydraulic pressure low or 88HQ overload!
Note: accumulator did not work 10 years ago. But strange in this subject, some units of the same frame work without problems for six consecutive months (peak season)
Note: type of fuel, Gas