水平井大规模压裂固井水泥石性能设计方法

Design Method of Cement Stone Performance for Large Scale Fracturing in Horizontal Wells

尹虎 赵修文 李黔 钟守明 李维轩

YINHu ZHAOXiuwen LIQian ZHONGShouming LIWeixuan

西南石油大学石油与天然气工程学院, 四川 成都 610500 中国石油新疆油田公司工程技术研究院, 新疆 克拉玛依 834000

Petroleum Engineering School, Southwest Petroleum University, Chengdu, Sichuan 610500, China Research Institute of Engineering Technology, Xinjiang Oilfield Company, Karamay, Xinjiang 834000, China

水平井大规模压裂对固井水泥石性能提出了更高的要求，不仅要求水泥石有一定的抗压强度，还需要具备一定变形能力。目前普遍采用的标准已不能满足水平井大规模压裂对水泥环密封性的要求。基于压裂工况条件下水泥环受力分析模型，综合考虑水泥环拉伸破坏和界面剥离破坏两种失效形式，提出了一种能满足大规模压裂密封要求的固井水泥石性能设计方法，建立了包含弹性模量、泊松比以及抗拉强度（或屈服强度）的固井水泥石性能指标控制图版，量化了水泥石的杨氏模量、泊松比、抗拉强度（或屈服强度）之间的关系。根据该指标控制图版进行水泥石性能设计，可以有效减少水泥环破坏的风险。建立了玛湖油田大规模压裂水平井固井指标控制图版，并根据该控制图版优选了弹韧性水泥浆体系，该体系现场应用10余口井，顺利完成了井口压力增量90 MPa的储层压裂改造，效果良好，达到了预期产量。

Large-scale fracturing of horizontal wells requires the higher performance of cement, which requires not only a certain compressive strength but also a certain deformation ability. The current commonly used standardisno longer meet the requirements of cement sheath sealing for horizontal well large-scale fracturing. Based on the stress analysis model of the cement sheath under fracturing conditions, a design method for cementing cement performance that can meet the requirements of largescale fracturing sealing is proposed with consideration of cement sheath tensile failure and interface failure. We established a cementing stone performance index control chart including elastic modulus, Poisson's ratio, and tensile strength (or yield strength), and quantified the Young's modulus, Poisson's ratio, and tensile strength (or yield strength) of the cement stone. The performance design of cement stone based on the index control chart can effectively reduce the risk of damage to the cement ring. A control board for the performance index of large-scale fracturing horizontal well cementing cement in the Mahu Oilfield was established. According to the requirements of the cement stone performance index control chart, the elastic-toughness cement slurry system was selected, and more than 10 wells were applied in the field. The reservoir fracturing reconstruction with a surface construction pressure of 90 MPa was successfully completed.

10.11885/j.issn.16745086.2021.04.28.09