石油勘探地下套管损坏载荷强度设计研究  

Research on Load Strength Design of Casing Damage in Oil Exploration

作　　者：练章华[1] 罗泽利 牟凤英 丁建东[3] LIAN Zhang - hua LUO Ze - li MOU Feng - ying DING Jian - dong(Southwest Petroleum University, Chengdu Sichuan 610500, China Quality Inspection Center of Petro China Tarim Oilfield Company, Korla Xinjiang 841000, China Oil Production Engineering Research Institute of Huabei Oilfield Company, Renqiu Hebei 062552, China)

机构地区：[1]西南石油大学,四川成都610500 [2]中石油塔里木油田公司质量检测中心,新疆库尔勒841000 [3]华北油田分公司采油工程研究院,河北任丘062552

出　　处：《计算机仿真》2017年第6期98-103,380,共7页Computer Simulation

基　　金：国家自然科学基金项目(51574198);国家教育部博士点基金项目(20135121110005)

摘　　要：套管在地层中多处于非均匀载荷之下,而非均匀载荷对套损影响甚大,在开采过程中,套管所受的非均匀载荷随着开采的进行而改变,设计的套管强度可能无法满足要求。针对上述问题,以弹塑性力学和现场数据为基础,建立了套管-水泥环-地层有限元模型,研究在不同的非均匀载荷、壁厚、钢级下套管的应力分布、变形大小、剩余强度等,从而研究非均匀地层载荷下套损的防控措施。研究表明:套管的最大应力随非均匀程度的增加而增大,且最大应力在最小水平主应力方向;在非均匀载荷作用下套管发生了(0.4-1)mm的椭圆变形,削弱了套管的抗挤能力;采用N80钢级的套管在不同的非均匀载荷下,最小剩余强度为(-9.0-75)MPa,而采用P110钢级套管其最小剩余强度为(175-282)MPa,因此提高钢级能有效防控非均匀地层的套损。A finite element model of casing - cement - formation is established based on elastic - plastic mechanics theory and the data of oilfield, the casing stress distribution, deformation and residual intensity under the condition of different non - uniform load, wall thickness and steel grade are analyzed, and the measures of prevention and control under non - uniform load are studied. The resuhs show that the maximum stress of casing rises with the increase of degree of loading＇s non - uniform and it is in the minimum horizontal principal stress direction. Furthermore, it generates （0. 4 - 1 ） mm elliptical deformation in the non - uniform load, which weakens collapsing strength of casing. At last, there is （ - 9. 0 - 75 ） MPa minimum residual intensity of N80 casing in the non - uniform load, but minimum residual intensity of P110 casing is （ 175 - 282 ） MPa in the same condition. It is the most effective measure of prevention and control casing damage of the non - uniform load.

关 键 词：非均匀载荷 套损 有限元法 防控措施 

分 类 号：TE25[石油与天然气工程—油气井工程]