Minimising the Risk of Hydrogen Embrittlement HE and Hydrogen Assisted Stress Cracking HASC Within Steel Lifting Products Used in the Marine Environment

Abstract

Hydrogen Embrittlement (HE) and Hydrogen Assisted Stress Cracking (HASC) are processes that detrimentally affect certain steels. These processes are understood and well documented. In recent years there has been an accumulation of product failures involving steel lifting components in the offshore industry. These failures have individually been investigated and confirmed as the result of Hydrogen Embrittlement (HE) and Hydrogen Assisted Stress Cracking (HASC). There continues to be an assumption that steel lifting components that comply with international standards are suitable for use offshore, however the corrosive environment and effects of dynamic load amplification on lifting components in the offshore environment significantly increase their susceptibility to HE and HASC. Our intention is to provide the offshore industry with technical guidance on the correct material selection in steel lifting components, over and above the requirements of international standards, to mitigate the risk of failure caused by Hydrogen Embrittlement (HE) and Hydrogen Assisted Stress Cracking (HASC). Our research highlights that a high-grade steel's hardness and toughness is critical. The definition of toughness in metallurgy and lifting is the ability of the material to absorb energy and to plastically ‘deform’ without fracturing.