HOW INFERIOR UT PROCEDURES AND PRACTICES ON PRESSURE VESSELS COST $1 MILLION IN TURNAROUND REPAIRS: CASE STUDY 2 OF２

摘要

This is Part 2 of a two-part case study discussing the costly repairs that were needed on newly fabricated pressure vessels. During the fabrication process, all of the Category "D" nozzle welds required ultrasonic examination per the requirements of Appendix 12 of the Section VIII, Div.1 ASME code. Upon delivery to the job site, the receipt inspection revealed seven of the eight vessels contained poor workmanship and rejectable defects in the Category "D" nozzle welds. A total of 57 nozzle repairs were needed prior to placing the vessels into service. The discrepant areas identified in this case study are as follows: 1. Inadequately written UT procedures; 2. Improper and poor implementation of the UT procedures; 3. Inadequate UT reporting; 4. Poorly trained UT examiners.