Incident Report

Subject:                         Hydro test failures

Date of Email reporting Incident:   Thu 31/10/2002 10:03

Report Detail:

There are risks and limits associated with cold water hydro tests! The pictures tell the story.
 
Water temperature is critical when hydro testing.  The latest edition of ASME Section VIII, Division 1, which is our rule book for new pressure vessel fabrication, RECOMMENDS that the metal temperature during hydrostatic or pneumatic pressure testing be maintained at least 30 degrees F. above the minimum design metal temperature, but need not exceed 120 degrees F., to minimize the risk of brittle fracture. The National Board of Boiler and Pressure Vessel Inspection Code, which is our rule book for repairing boilers and pressure vessels, REQUIRES that the metal temperature for the pressure test shall be in accordance with the original code of construction but not less than 60 degrees F. unless...toughness characteristic information...indicating acceptability of lower test temperatures is made available.  And again the max. metal temperature allowed is 120 degrees F

ABB Guidance (ETOL Procedures) can be found in EUT..299C Appendix E
Guidance on Hydrostatic Pressure Testing on Vessels.