CHALLENGES IN KIH TESTING USING WOL SAMPLES FOR PIPELINE APPLICATIONS

Gaseous Hydrogen can have detrimental effects on the mechanical performance of carbon steels, and those effects need to be taken into account for the proper design of pipelines for H-2 transportation systems. ASTM E1681 is the standard test method used to evaluate fracture toughness in an H-2 environment and presents the possibility of testing under constant loading or under constant displacement conditions. Given the comparative simplicity of testing self-loaded specimens in constant displacement, this type of test has become a "standard" for the industry. However, satisfying the different validity checks required by the testing standard presents several challenges that seems to be very difficult to solve. The present paper explores the limits in terms of dimensional requirements and stress intensity factor solutions using finite element simulations and experimental testing.