J. Zhong, Guanghui Zhao, Litong Wang, Yi He, Siou-Han Hu
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引用次数: 0
Abstract
Coiled tubing (CT) is a joint-less long oil pipe that is wound around a reel and can be run and pulled continuously. Due to the particularity of the operating process, low-cycle fatigue (LCF) failure of the CT constitutes the main production cost. Aiming at the characteristics of small diameter and thin wall of CT, a single-edge-notched (SEN) arc specimen was designed and machined. LCF tests were conducted with force-controlled mode. Cyclic softening of the CT steel was presented and crack growing rates were measured. Meanwhile, finite element simulation was carried out to obtain the relationships among J-integral, crack size and load. Based on the experimental and numerical results, the speed of the LCF crack growth of the CT steel is expressed as an explicit function of the J-integral. It provides a basis for predicting the LCF life of the CT under working conditions from the perspective of crack propagation.
期刊介绍:
The journal is publishing scientific papers dealing with the following problems:
Mechanics of Solid Bodies;
Mechanics of Fluids and Gases;
Dynamics of Mechanical Systems;
Design and Optimization of Mechanical Systems;
Mechanical Technologies.