1、Lessons Learned Entry: 0241Lesson Info:a71 Lesson Number: 0241a71 Lesson Date: 1993-07-15a71 Submitting Organization: LERCa71 Submitted by: S. PapellSubject: High Pressure Steel Pipes Description of Driving Event: A 125 pound per square inch pressure air line in a ground trench, used to supply test
2、facilities, failed by splitting along the longitudinal weld. The 10 inch diameter steel pipe ruptured for a distance of about 15 feet. As a result of this failure, four manhole covers were blown into the air.The air line that failed was in a covered ground trench and had been in place for about 15 y
3、ears. During this time, moisture was present from surface water leakage and considerable corrosion had taken place on the pipe outside diameter. Inspection of the failed pipe revealed that the original thickness of 1/4 inch was reduced to almost zero in some places as a result of the corrosion. The
4、failure was due to the corroded pipe no longer being able to withstand the internal working pressure.Lesson(s) Learned: Unprotected steel pipes in below ground trenches, when under pressure, are subject to catastrophic failure due to corrosion.Recommendation(s): Install seamless wrought iron piping
5、with a bituminous coating protected by magnesium anodes for corrosion resistance.Evidence of Recurrence Control Effectiveness: N/AProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Documents Related to Lesson: N/AMission Directorate(s): N/AAdditional Ke
6、y Phrase(s): a71 Pressure VesselsAdditional Info: Approval Info: a71 Approval Date: 1994-06-15a71 Approval Name: Maria Havenhilla71 Approval Organization: LERC/EBASa71 Approval Phone Number: 216-977-1483Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
