Many tools and facilities are required in expensive cement plug placement. Cement plug placement in deep and high temperature wells is of high safety risk. To minimize this risk and address the problems associated with cement plug placement, a high strength temporary plugging agent is required. The temporary plugging agent should have such properties as high strength, simplicity in preparing and convenience in pumping. Laboratory experiments have been conducted to select the core materials such as gelling agent and suspending agent, and to develop the required activator. Based on literature survey and laboratory experiments, a high strength temporary plugging agent GQ-1 was developed. GQ-1 has a wide density range (1.50 - 1.90 g/cm3) and stable properties. The mobility, flow index and consistency of GQ-1 are all in reasonable ranges. GQ-1 is compatible with commonly used drilling fluids, and the plug formed by GQ-1 has high strength. GQ-1 can be mixed with mud circulation and mixing systems, and pumped with drilling pumps. GQ-1 has been applied on two wells (Well Yangdu-H2, for instance) with great success. Pressure test on the plugs formed by GQ-1 in the two wells showed 63.3 MPa and 64.3 MPa, which were qualified. Success of the application on the two wells provided a technical support for the spreading of GQ-1.%注水泥塞施工设备多、成本高,深井、高温井注水泥塞安全风险较为突出,因此研究一种强度高、配制简单、泵送方便、风险较小的高强度成塞暂堵剂具有较大的价值.开展了高效成塞暂堵剂核心材料胶凝剂、悬浮剂的优选和活性剂研制,通过对文献查阅研究,进行了大量室内实验,研究形成了高强度成塞暂堵剂GQ-1体系.该体系密度可调节范围大(1.50～1.90 g/cm3)、浆体稳定性好,流动度、流性指数、稠度均在合理范围内,与钻井液相容性好,成塞强度高.该体系可用钻井液循环系统、加重装置配制,钻井液泵注替.研究成果在洋渡-H2等2井次进行了试验,施工顺利,试验井回接固井后分别试压63.3、64.3 MPa合格.试验的成功为该体系推广应用提供了技术支撑.
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