Defect Condemnation for Submarine Pressure Hull Welds
Abstract
The British standards for submarine pressure hulls indicates that the presence of any lack of fusion defects in the weld is cause for rejection. However, depending upon the size and location of the defect, certain amounts of lack of fusion may be acceptable. Six explosion bulge test panels were welded to have lack of fusion flaws; two panels had root flaws and the other four had cap flaws. Explosion bulge tests were performed to determine if the welds could resist crack propagation beyond the limits of the bulge apex. Prior to testing, the welds were examined with manual ultrasonics and computer aided ultrasonics. They were also radiographed at plus and minus 20 degrees to normal (standard radiography would be shot at normal). The NDT was conducted to relate performance back to NDT (as opposed to just defect size and location). Following explosion testing, the welds were sectioned and opened to determine the true defect extent. Defect size and location was found to be less of a determining factor in the quality of the weld than the base properties of the weld and steel. It was found that condemnation criteria should be based on these base properties as well as on the size and location of defects.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1998
- Accession Number
- ADA354387
Entities
People
- J. F. Porter
- J. R. Matthews
- T. Macadam