API TR 934-F Part 2

This technical report documents a critical assessment of the existing literature on IHAC of V-modified Cr-Mo steels for use in interpreting the results of the present laboratory work, so as to establish a definitive characterization of the H cracking resistance of this steel class.

Since these modern Cr-Mo-V steels are of relatively high purity, and thus retain a low FATT after laboratory simulation of in-service temper embrittlement, the data base for 2¼Cr-1Mo shown in Figure 1 provides a context for assessment of the IHAC performance of V-modified grades. Hydrogen cracking of less-pure V-modified Cr-Mo steels was not considered in this review.

The content of this technical report is chronologically organized into initial and more modern works, as justified by improvement in test execution, data analysis, and reporting, as well as the evolution from laboratory to commercial scale heats of Cr-Mo-V.