R omain Chantalat

Abstract

In the current offshore perspectives, the energy transition initiative is involved in the expansion of knowledge and the development of new systems, thus appealing expanded use of Flexible Pipes to integrate renewable energy with hydrogen applications. Within this context, subsea pipelines are needed to transport gaseous hydrogen, a non-usual gas within standard offshore Oil & Gas sector and well known for its ability to cause steel embrittlement. For these reasons, caution must be taken, and suited qualification testing needs to be conducted to propose a reliable transportation solution. Therefore, to better understand the influence of H2 on carbon steel armour wires used in unbounded flexible pipes, mechanical tests, such as fatigue, toughness and crack propagation tests have to be performed. This study seeks to correlate the bending behaviour in air and in H2 environment in order to identify possible mechanical property changes due to the hydrogen environment.

The work presented here focuses on the characterisation of two carbon steel grades tested in air and H2. The impact of H2 on the toughness, the crack growth and performance in fatigue will be addressed. The data allows to select materials compliant with the hydrogen transport application and to acquire the data needed to perform the detailed engineering of the flexible pipe.

Session