scope:

This standard test method establishes two recommended methods for measuring the relative carburization resistance of alloys for tubes intended for service in ethylene cracking furnaces, or for assessing the performance of these tubes after service. Application procedures for the two methods are defined in detail. The combustion analysis method is preferred because it is quantitative. The chemical etching method is simpler and less expensive, but is only semiquantitative. Other methods considered and the reasons they are not recommended are discussed in Appendix A.

This standard is intended to assist designers, operators, producers, fabricators, users, and testing laboratories in the measurement of the carburization of alloys used for ethylene cracking furnace tubes.

This standard was originally prepared in 1998 by Task Group T-5B-11, a component of Unit Committee T-5B on High-Temperature Materials Performance. It was reaffirmed in 2002 by Specific Technology Group (STG) 37 on Process Industry - High Temperature. It is issued by NACE International under the auspices of STG 37.