1、Lessons Learned Entry: 0026Lesson Info:a71 Lesson Number: 0026a71 Lesson Date: 1992-09-04a71 Submitting Organization: KSCa71 Submitted by: Lisa L.MusgraveSubject: Critical Gaseous Helium (GHE) Purge Operations Description of Driving Event: The launch operations area fuel cell servicing system (FCSS)
2、 LH2/GH2 system provides for the loading of LH2/GH2 to the orbiter at pads A and B. The LH2 FCSS low pressure sample panel and the fixed service structure FCSS GN2/GHe service panel are utilized for the helium sweep flow purge to the FCSS hydrogen vent stack. Three critical items are in the GN2/GHE
3、service panel and two are located in the low pressure sample panel. Failure of a critical item will disable the sweep flow purge to the vent stack, which is performed prior to initiating hydrogen steady state venting from the dewar.Lesson(s) Learned: Failure/corrosion/clogging of critical hardware i
4、n fuel cell servicing service system panels may cause ineffective purge and/or explosion.Recommendation(s): Redesign purge system to modify purge path and relocate interface with vent system to provide adequate purge capability.Evidence of Recurrence Control Effectiveness: N/AProvided by IHSNot for
5、ResaleNo reproduction or networking permitted without license from IHS-,-,-Documents Related to Lesson: N/AMission Directorate(s): a71 Space Operationsa71 Exploration SystemsAdditional Key Phrase(s): a71 Energetic Materials - Explosive/Propellant/Pyrotechnica71 Facilitiesa71 Ground Operationsa71 Gro
6、und Equipmenta71 Hardwarea71 Pressure VesselsAdditional Info: Approval Info: a71 Approval Date: 1994-06-01a71 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-,-,-
