Technical basis for ASME section VIII code case 2235 on ultrasonic examination of welds in lieu of radiography

摘要

In 1996, Code Case 2235, which allows ultrasonic examination of welds in lieu of radiography for ASME section VIII Division 1 and Division 2 vessels, was approved by the ASME B&PV Code Committee. This Code Case has been revised to incorporate: (1) a reduction in minimum usable thickness from 4" (107.6 mm) to 0.5" (12.7 mm) and, (2) flaw acceptance criteria including rules on multiple flaws. A linear elastic fracture mechanics procedure has bene used in developing the flaw acceptance criteria. This paper presents the technical basis for Code Case 2235.