In the past 5 years, Conventional Non-Destructive Examination (NDE) for High-Temperature Hydrogen Attack (HTHA) has been improved with remarkable success. This technology, combined with emerging Fitness-for-Service (FFS) methodologies, has been used in the evaluation of equipment in HTHA service with a higher level of confidence. Some of these evaluations have led to a systematic approach to continued operation, limited service, or retirement decisions not possible just 5 years ago. This paper will highlight some of the ongoing advances of the HTHA Joint Industry Project (JIP) to date and provide a preview into upcoming developments in the NDE and FFS codes. Some case studies will be presented along with recent advances in laboratory methods for HTHA prediction.
Key words: High-Temperature Hydrogen Attack, HTHA, Nelson Curve, Carbon Steel, C-0.5Mo, API RP 941, decarburization, NDT, NDE, non-destructive examination