摘要
目前国内外常用巴西劈裂抗拉强度作为评价储气库水泥环封隔完整性的关键指标之一,但其测试过程中受加载点应力集中的影响导致测值偏低,进而无法设计、优选出满足储气库封隔完整性要求的水泥浆体系。文章根据储气库注气过程中水泥环受周向拉伸应力的特点,研制了水泥石拉伸抗拉强度测试装置并提出了相应的测试方法,测试并分析了不同体系水泥石拉伸抗拉强度、巴西劈裂抗拉强度和抗压强度三者之间的关系,优选了满足XX储气库生产运行要求的水泥浆体系。研究结果表明:评价水泥环封隔完整性、优选水泥浆体系应采用拉伸抗拉强度作为关键指标之一,拉伸法解决了巴西劈裂法应力集中导致抗拉强度测值偏低的问题,其测得的抗拉强度比巴西劈裂法测得的要大40%,拉伸法拉压比为0.054~0.076,巴西劈裂法拉压比为0.038~0.055。该成果应用于XX储气库水泥浆体系优选研究,优选出10%胶乳水泥浆体系更能保证水泥环的封隔完整性,对储气库水泥浆体系优选研究和油气田“降本增效”具有重要借鉴意义。
At present,Brazilian splitting tensile strength is commonly used as one of the key indexes to evaluate the sealing integrity of cement sheath for gas storage.However,due to the stress concentration at the loading point in the testing process,the measured value is low,so it is impossible to design and optimize the cement slurry system that meets the sealing integrity requirements of gas storage.According to the characteristics of cement sheath subjected to circumferential tensile stress during gas injection in gas storage,a test device for the tensile strength of cement stone was developed and the corresponding test method was proposed.The relationship among the tensile strength,Brazilian splitting tensile strength and compressive strength of cement stone of different systems was tested and analyzed,and the cement slurry system meeting the production and operation requirements of XX gas storage was selected.The results show that:The tensile strength of cement should be used as one of the key indexes to evaluate the sealing integrity of cement sheath and optimize the cement slurry system.The tensile strength measured by the tensile method solves the problem of low tensile strength measured by the Brazilian test due to stress concentration.The measured tensile strength is about 40%higher than that measured by the Brazilian test,with a tensile farad compression ratio of 0.054~0.076 and a Brazilian splitting farad compression ratio of 0.038~0.055.This achievement has been applied to the optimization research of cement slurry system for XX gas storage well,and the 10%latex cement slurry system has been selected to better ensure the sealing integrity of the cement sheath.It has important reference significance for the optimization research of cement slurry system for gas storage well and the"cost reduction and efficiency increase"of oil and gas fields.
作者
方仲旗
谭元铭
严俊涛
王新强
侯凡
朱贵攀
廖世钊
FANG Zhongqi;TAN Yuanming;YAN Juntao;WANG Xinqiang;HOU Fan;ZHU Guipan;LIAO Shizhao(Cementing Company,Sinopec Southwest Petroleum Engineering Co.,Ltd.,Deyang,Sichuan 618000,China;Chongqing Shale Gas Exploration and Development Co.,Ltd.,Chongqing 401120,China;Downhole Operation Company of PetroChina Qinghai Oilfield Company,Mangya,Qinghai 816499,China;Xi′an Shiyou University,Xi′an,Shaanxi,710065,China)
出处
《钻采工艺》
CAS
北大核心
2023年第3期128-134,共7页
Drilling & Production Technology
基金
中石化西南石油工程有限公司固井分公司科研项目“油气井弹韧性水泥浆体系研究与应用”(编号:XNGJ20220906-2)。
关键词
储气库
水泥石
抗拉强度
拉伸断裂
巴西劈裂
拉压比
体系优选
gas storage
cement stone
tensile strength
tensile fracture
Brazilian split
tension-compression ratio
system optimization
