GE gas turbine bearing cooling fan inlet screen large differential pressure automatic load reduction exception events

GE gas turbine bearing cooling fan inlet screen large differential pressure automatic load reduction exception events - 2020 12 - 18 Chen Haifu 1, the occurrence of the incident on October 6, 2014, any operation personnel supervisor found # 5 combustion engine bearing cooling fan inlet differential pressure switch alarm, lian kai fan fan automatically shut down after the no. 1, no. 2 the entrance to the differential pressure switch alarm, still again united fan automatically shut down after the rev 1 2 fan, differential pressure switch alarm again, rate of gas turbine began after a predetermined time delay 15 s automatic load down. Immediately clear installation personnel fan inlet screen. Cleaned up, switch back to normal. 2, root cause analysis ( 1) Logic design is not reasonable, logical Settings now allows only one bearing cooling fan operation, when the filter differential pressure big, will cause two fan frequent start-stop, unit output reduction. （ 2) Mesh set unreasonable, the two share a set of mesh turbines. 3, preventive measures, 1) Optimization of logic, when filter differential pressure big, interlock start another fan, fan running at the same time, maintain two people determine whether to stop another fan. （ 2) Suggest add one set of mesh, one shipment.