为有效避免低压易漏长裸眼段固井漏失,提高固井质量,从井眼准备、水泥浆体系、固井工艺和注替技术四方面进行综合治理。实施固井防漏工艺的前提是分析薄弱层位,掌握漏点位置,确定地层"四压力"数据,尤其是漏失压力。通过提高地层承压能力、使用分级或尾管悬挂等固井工艺,开发高强低密度水泥浆体系,优化浆柱结构,减小尾浆附加量,合理设计注、替浆排量,控制施工泵压,使得环空动液柱压力小于地层漏失压力,是低压易漏井防止固井漏失和提高固井质量的主要工艺技术。
To guarantee leak resistance of cementing and cementing quality improvement in low pressure and easy-to-loss wells,borehole preparation,formation lithology and pressure feature,cementing slurry,cementing technologies and displacement techniques must be put into consideration. The basis for carrying out leak resistance techniques is to grasp the formation leak point and to obtain the pressure data,especially the leakage pressure. The main technologies and technique for leak resistance of low pressure,easy-to-loss and long open-hole well are: enhancing formation pressure-bearing,using two-stage cementing and liner hanging cementing techniques,developing high strengthlow density cementing slurry,decreasing additional amount of tailing slurry,optimizing rational slurry column structure,designing flow rate of cement grouting and cementing displacement and controlling pump pressure.