1、Lessons Learned Entry: 0102Lesson Info:a71 Lesson Number: 0102a71 Lesson Date: 1992-08-11a71 Submitting Organization: KSCa71 Submitted by: David PenningtonSubject: High Pressure Shutoff Valves; Vacuum Pump Isolation Valve Description of Driving Event: A vacuum pump isolation valve burst at the Pad B
2、 high pressure gas storage battery. The cause of the incident has been attributed to the seepage of pressure from the wheel valves after they were turned off as part of a safing operation. The wheel valve o-ring does not always seat properly. Normally this would not affect the remainder of the syste
3、m, the seepage pressure would be confined. However, when the vacuum pump was connected to the system, the seepage pressure (1500 psi) was greater than the design capacity of the vacuum pump isolation valve and thus overpressurization occurred.Lesson(s) Learned: 1. Failure to establish a preventative
4、 maintenance program for two 6000 psi shutoff valves resulted in a close call when they began leaking2. Failure to use valves capable of withstanding system pressures resulted in a “close call“ when a valve exploded.Recommendation(s): 1. Establish a preventative maintenance program for components in
5、stalled in critical high pressure systems.2. Ensure that any isolation valve used in a pressure system can withstand the highest pressure of the overall system.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Evidence of Recurrence Control Effectivene
6、ss: N/ADocuments Related to Lesson: N/AMission Directorate(s): a71 Exploration Systemsa71 Sciencea71 Space Operationsa71 Aeronautics ResearchAdditional Key Phrase(s): a71 Facilitiesa71 Ground Equipmenta71 Hardwarea71 Industrial Operationsa71 Pressure VesselsAdditional Info: Approval Info: a71 Approval Date: 1994-06-02a71 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-,-,-
