scope:

The overall goal of the research program reported in this WRC Bulletin was to demonstrate the ability to characterize and monitor various aspects of crack propagation in pressurized process equipment exposed to wet H2S environments.The specific factors examined were

(1) the mechanical/environmental effects such as internal pressure, pressure cycling, and environmental severity;

(2) active cracking sites in pressurized equipment;

(3) results obtained by ultrasonic and acoustic emission and wet fluorescent magnetic particle NDE techniques compared to those obtained by destructive examination, including mechanical testing and metallography; and

(4) the ability of fabrication and repair techniques to reduce or prevent wet H2S cracking and any procedures that might increase susceptibility to cracking. The results of this study validated test methods for wet H2S cracking developed previously and showed applicability to refinery service environments. The work presented in this document - WRC Bulletin 396 - was sponsored by the Materials Properties Council, Inc., and the American Petroleum Institute under the direction of the Task Group on Materials and Corrosion Research of the API Subcommittee on Corrosion and Materials. This work is also reported as API Publication 939