Session: MF-02-01 Materials for Hydrogen Service (Joint with CS-02 and HT-07) - Evaluating Component Life

Paper Number: 105972

105972 - Shell Experience in Repurposing Vintage Pipeline Materials to Hydrogen Service 

A study was performed on the suitability of an offshore vintage API 5L X60 grade pipeline material for conversion to gaseous hydrogen service. The study involved mechanical slow strain rate testing,  fracture toughness and fatigue crack growth testing on the representative material microstructures in two environments - gaseous hydrogen at several partial pressures of H₂ and wet sour environments at several partial pressures of H₂S at low pH to establish analogues with the sour service experience. The study found satisfactory mechanical and fracture properties for the material with consistent fatigue crack growth behaviours to those published by Sandia (Ref PVP2022-84757) for DK above 5 MPa√m and fracture toughness values in-line with expectations for hydrogen service. At DK values below 5 MPa√m the fatigue crack growth curve is above those predicted by Sandia National Laboratories (PVP2022-84757) or ASME B31.12 in certain cases, and is suspected to be driven by sustained cracking. The study explored the time dependent cracking phenomena which may develop under sustained crack tip loading above a certain maximum stress intensity factor value in gaseous hydrogen service. It was found that the cracking phenomena is dependent on the microstructure (seam weld versus parent metal) and the partial pressure of H₂. The study also examined the welding residual stresses in the seam weld of the pipe by a deep hole drilling method and further the residual stresses in the laboratory test sample were also obtained by a slitting method to contextualise the fracture measurements.

Presenting Author: Bostjan Bezensek Shell Global Solutions UK

Presenting Author Biography: PhD in fracture mechanics for structural integrity management from University of Glasgow, Scotland
20 years of experience with pressure vessel, piping and recently upstream pipelines in the Energy sector.

Lead of the Shell research programme on the performance of material in gaseous hydrogen service for transportation and storage.

Authors:

Bostjan Bezensek Shell Global Solutions UK
Sarah Hopkin Shell Global Solutions B.V.
Tom Martin Shell Global Solutions B.V.
Wim Guijt Shell Global Solutions B.V.