川东天东区块侏罗系地层高压喷射钻井技术

针对川东天东区块上部侏罗系砂泥岩地层机械钻速不高的钻井难题,开展了高压喷射钻井现场试验。选择侏罗系为主要试验地层,三叠系须家河组为探索试验地层,应用HJT537GK、HJT617G型钻头,配备全新钻铤和钻杆,采用三强结构聚合物无固相钻井液体系,强化钻井参数,分为第一、第二阶段主要试验和第三阶段探索试验,在天东区块进行了高压喷射钻井试验。试验中最高泵压达到31 MPa,平均机械钻速7.45 m/h,与应用常规钻井技术的邻井相比,相同地层钻速提高80%,钻井周期平均缩短3~4 d。 

High-Pressure Jet Drilling Technology in Jurassic Formation in Eastern Sichuan

As the ROP is not high when penetrating into the Jurassic in Eastern Sichuan Field,the high-pressure jet drilling test was carried out.The Jurassic was the main experiment formation and Xujiahe Formation of Triassic is the pilot experiment formation.The bits with Model HJT537GK and HJT617G and new drill collar as well as drill pipe were used.Solid free drilling fluid system of "three-strengths" structure was adopted to intensify the drilling parameters.Main experiments were conducted in stage 1 and stage 2 and exploring experiment in stage 3.The high pressure jet drilling experiment was conducted in TD Block,the highest pump pressure during the experiment was 31 MPa and the average ROP was 7.45 m/h,80% higher than conventional drilling in offset wells in same formation.The average drilling time was shortened by 3 to 4 days.High pressure jet drilling experiment has been successful for raising drilling rate,and reached the expected goal.