1.1 This Test Method describes procedures for evaluating the resistance of pipeline steels to stepwise cracking induced by hydrogen absorption from aqueous sulfide corrosion. The test is applicable to line pipe with wall thicknesses of 5 to 30 mm.

1.2 The test procedure consists of exposing unstressed coupons to a solution of synthetic seawater saturated with hydrogen sulfide at ambient temperature and pressure at a pH in the range of 4.8 to 5.4. After a specified time the coupons are removed and evaluated.

1.3 The test is not intended to duplicate service conditions. It is intended to provide a procedure that will give a reproducible environment capable of distinguishing the susceptibility of different samples to stepwise cracking in a relatively short time.

NOTE: The length of the test may not be sufficient to develop maximum cracking in any given steel but has been found to be adequate for the purpose of this test.

1.4 This Test Method does not include acceptance or rejection criteria. The methods used for determining acceptance and rejection, for comparing different steels, for screening of steels, or for other purposes are beyond the scope of this Standard.

Historical Document 1984