Assessment on failure pressure of high strength pipeline with corrosion defects

• A new prediction formula for high strength steel pipelines is proposed.
• Strain hardening behavior of material is considered.
• Ramberg–Osgood hardening stress–strain relation is adopted.
• Extensive FEA simulations (195 cases) are built.
• Seventy nine groups of burst tests data are collected to verify the reliability of formula.

An accurate prediction on the failure pressure of line pipe is very important in the engineering design and integrity assessment of oil and gas transmission pipelines. This paper analytically investigates the failure pressure of line pipes with or without corrosion defects, and focus on the high strength steels. Based on von Mises strength failure criterion, a classic strength failure criterion, the failure pressure of end-capped and defect-free pipe pM is theoretically deduced with the strain hardening material. In order to derive a general solution for corrosion defect assessment of high strength pipelines, an extensive series of finite element analyses on various elliptical corrosion defects was performed. Finally, a new formula for predicting the failure pressure of corroded pipe in the material of high strength steels is formulated, based on the FE models and pM, and is validated using 79 groups of full-scale burst test data, which contain the low, middle and high strength pipeline. The results indicated that the proposed formula for predicting the failure pressure is closely matches the experimental data for the high strength steels.