Session: MF-01-01 Application of Fracture Mechanics in Failure Assessment

Paper Number: 123037

123037 - Ductile Fracture Criterion Parameter Calibration and Analysis:x80 Pipe Steel 

High-strength pipeline steel is widely used in oil and gas transmission, and the types of failure caused by its complex operating environment are also the focus of scholarly research, of which ductile fracture is one of the causes that cannot be ignored, in order to explore the fracture mechanical properties of high steel grade pipes, the ductile fracture criterion is applied to the fracture failure evaluation of pipeline steel. This paper takes X80 high steel grade pipe as the research object, designs four types of six different stress concentration coefficients of tensile specimens to obtain the basic mechanical property parameters and fracture strains of the material. The Ramberg-Osgood model is used to represent the hardening effect of the material, the ABAQUS software display module is used to construct a symmetric finite element model of the specimen, and then the experimental-simulation hybrid method is used to extract the stress triaxiality and the Lode parameter, which are difficult to obtain in experiments. Three of the specimen data were selected to calibrate the fracture parameters for the three fracture criteria. A comparative analysis of the predictions of the different criteria using the remaining three specimen data and the construction of the material fracture trajectory diagram. The study shows that: the data extraction of specimens with different stress concentrations by the experimental-simulation hybrid method can be used to calibrate the parameters of the fracture criterion; both the Oyane and DF2014 ductile fracture criteria can predict the ductile fracture of X80 high-strength pipe steel in uniaxial tension, in-plane tension and shear stress, while the DF2014 ductile fracture criterion provides the most accurate and flexible characterization of the fracture behaviour under different stresses, and its damage evaluation model can be used to predict the ductile fracture of high-strength pipe steel. The research can be used to inform the evaluation of ductile fracture failure of high steel grade pipes by the ductile fracture criterion.

Presenting Author: Xueming Zhu China University of Petroleum-Beijing

Presenting Author Biography: I am currently pursuing my PhD at China University of Petroleum (Beijing). My major is safety science and engineering, and my research interests are pipeline integrity management and equipment reliability.

Authors:

Xueming Zhu China University of Petroleum-Beijing
Zhiyang Lv China University of Petroleum-Beijing
Jian Shuai China University of Petroleum-Beijing
Lei Shi Sinopec (Dalian) Research Institute of Petroleum and Petrochemicals Co., Ltd
Shengyang Yu China National Oil and Gas Exploration and Development Co
Gang Xia China National Oil and Gas Exploration and Development Co