文献类型：期刊文献

英文题名：Experimental and analytical studies on the pullout strength of round thread casing connections

作者：Gao, Lianxin[1];Shi, Jiaoqi[2]

机构：[1]E China Univ Sci & Technol, Minist Educ, Key Lab Pressure Syst & Safety, Shanghai 200237, Peoples R China;[2]China Natl Petr Corp, Tubular Goods Res Inst, Xian 710065, Shaanxi, Peoples R China

年份：2013

卷号：20

期号：6

起止页码：497

外文期刊名：INDIAN JOURNAL OF ENGINEERING AND MATERIALS SCIENCES

收录：;EI(收录号：20140517244522);WOS:【SCI-EXPANDED(收录号:WOS:000332438000007)】；

基金：This study was supported by Tubular Goods Research Centre of CNPC. The authors would like to thank Dr. Junren Xie, Senior Engineer, C-FER Technologies Canada, for improving the paper.

语种：英文

外文关键词：Round thread casing; Pullout strength; Full-scale test; Finite element analysis

摘要：Pullout failure is one of the primary failure modes of API round thread casing connections. Make-up torque and thread tolerances are the two most important factors that can affect the pullout strength. In this paper, the pull-Out failure process and mechanism are studied using the finite element analysis (FEA) method. In addition, the effects of make-up torque and thread tolerances on the pullout strength of API round thread connections are analyzed. The FEA results are validated through tension tests on a total of 34 pins and 17 couplings. The results show that pull-out failure initially occurs at the first and second teeth near the coupling end. At the same time, thread tolerances especially unmatched taper have notable effect on pullout strength. The tests show that higher make-up torque levels are beneficial to the pullout strength. Make-up torque 15-20% higher than the maximum API limit is recommended when round thread casing connections are used in oilfield.