1、Lessons Learned Entry: 0129Lesson Info:a71 Lesson Number: 0129a71 Lesson Date: 1992-08-24a71 Submitting Organization: KSCa71 Submitted by: Lisa L. MusgraveSubject: The Oxygen Vent System. Description of Driving Event: The vacuum servicing units provide the capability to evacuate the PRSD tanks and t
2、he relief line. The unit consists of a skid mounted frame, electrical and fluid control panels and an electric motor driven vacuum pump. If the vacuum servicing unit is left connected to the suction line, inadvertent opening of manual valve A81992 could subject the pump to 935 psig from the cryo val
3、ve panel. This is beyond the units capability and could expel pump oil through the vent system.Lesson(s) Learned: Failure to protect the vacuum servicing unit from inadvertent actuations of the 935 psig cryo valve panel could result in damage to flight hardware.Recommendation(s): Install a pressure
4、actuated check valve to prevent the high cryo pressure from affecting the vacuum servicing unit.Evidence of Recurrence Control Effectiveness: N/ADocuments Related to Lesson: Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-N/AMission Directorate(s): N
5、/AAdditional Key Phrase(s): a71 Ground Operationsa71 Ground Equipmenta71 HardwareAdditional Info: Approval Info: a71 Approval Date: 1994-06-03a71 Approval Name: James G. Klinea71 Approval Organization: KSC/HEIa71 Approval Phone Number: 407-867-7614Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
