1、Lessons Learned Entry: 0315Lesson Info:a71 Lesson Number: 0315a71 Lesson Date: 1993-10-20a71 Submitting Organization: MSFCa71 Submitted by: White, MargoSubject: Pressure Systems, Galvanic Corrosion, Rupture, Explosion Description of Driving Event: An explosion occurred at the test stand complex 500
2、at MSFC. The explosion was a result of a massive GH2 leak, which occurred in an underground 3.5 inch OD x 0.6 inch thickness wall schedule XX ASTM A106 grade B carbon steel line. This failure was the result of galvanic corrosion over a prolonged period of time and the application of high pressure ga
3、s to a resultant thin pipe membrane.Lesson(s) Learned: Pressure systems buried in the earth are subject to corrosion due to galvanic action or inadequate protection from galvanic or stray current; in time the strength of the system and the pressure retaining capability will be reduced to the degree
4、that rupture or explosion may occur.Recommendation(s): Consider installing pressure systems above ground; if not feasible, then assure the integrity of the pressure system coating at the time of installation and locate system such that it is not in proximity to sources of stray electrical current. P
5、erform periodic proof pressure tests on pressure systems.Evidence of Recurrence Control Effectiveness: Proof pressure testing has been utilized for many years to recertify pressure systems, both ground and flight, and has proven to be effective. It is self-evident that avoiding stray electrical curr
6、ent and assuring adequate system coating would reduce the probability of catastrophic events.Documents Related to Lesson: Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-N/AMission Directorate(s): N/AAdditional Key Phrase(s): a71 Energetic Materials
7、- Explosive/Propellant/Pyrotechnica71 Facilitiesa71 Pressure VesselsAdditional Info: Approval Info: a71 Approval Date: 1994-08-17a71 Approval Name: White, Margoa71 Approval Organization: EH44a71 Approval Phone Number: 205-544-4182Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
