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[MW:36088] Request for Technical Opinion – Leakage in SS 316L Schedule 10S Line After 4 Months of Service

By Materials & Welding

Dear All,

We would appreciate your technical opinion regarding a leakage issue observed in stainless steel piping after several months of operation.

Background:

  • Line sizes: 2" and 6" 361L Stainless Steel (Schedule 10S)
  • NDT coverage: 10% completed as per project requirements
  • Hydrostatic test: Successfully passed without any leakage
  • Records related to line preservation after reinstatement are not available, as the system was under the control of the Pre-Commissioning and Commissioning teams
  • The line has been in service for approximately 4 months

Issue:
Leakage has recently been observed at several locations, including:

  1. Weld joints
  2. Pipe body/base material
  Considering that the line successfully passed hydrotesting and has been operating for several months before the leakage occurred ,  

 Could you please share your views on the potential reasons

Thank you in advance for your valuable inputs.

Best Regards,
Karuppasamy

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