基于触变水泥浆的套漏井不留塞封堵技术

套漏井不留塞封堵工艺要求封堵剂在地层里能驻留、井筒里能冲洗出来,油田常用的G级油井水泥性能难以满足要求。针对水泥浆封堵剂不留塞封堵工艺的要求,开展触变水泥浆配制和性能评价。在室内不同温度下对触变水泥浆的流变性、静切力、静置增稠和剪切稀释特性、稠化性能和水泥石的抗压强度等进行了测试,分析了触变水泥浆作为不留塞封堵剂比G级油井水泥的优势。根据不留塞封堵施工过程封堵剂的状态,采用常压稠化仪模拟了封堵套漏井的施工过程;了解触变水泥浆在施工过程稠度变化规律,为优化封堵施工各道工序完成时间提供依据,尤其是确定反冲洗时间这一关键参数,为不留塞封堵施工成功和确保施工安全提供了参考。现场采用触变水泥浆实施不留塞封堵施工获得成功。

Plugging technique without jam using thixotropic cement slurry

The plugging technology of casing leaking well without jam is required to be able to stay in the stratum and to flush out in the wellbore, and the performance of G-class oil well cement used in oilfield is difficult to meet the requirements. In the workover requirement of plugging technology of cement plugging agent without jam, the research on the characteristics of thixotropic cement is carried out, and the rheological properties, static shear force, thickening while stay and shearing dilution characteristics, thickening curve and compressive strength of cement rock are tested and evaluated in the laboratory. Analyzes the advantages of thixotropic cement agent than G-class oil well cement. According to the state of plugging agent in workover process, the workover process of plugging casing leaking well is simulated by thickening instrument. Understanding the regularity of the variation of the consistency of the thixotropic cement slurry in the workover process can provide reference for optimizing the process completion time of the plugging, especially determining the key parameter of the flushing time, which provides a guide for the success of plugging and ensuring the workover safety. The application of Thixotropic cement to the site workover is successful.