哈山3井火成岩地层快速钻井技术

Fast Drilling Technique through Igneous Rocks in Well Hashan 3

为解决准噶尔盆地火成岩地层岩石坚硬、可钻性差、井斜问题突出等技术难点,进行了火成岩地层"PDC钻头+扭转冲击工具"复合钻井技术研究。针对火成岩地层岩性特点和钻井技术难点,通过研制具有较强耐磨性的311.1mm PK6245MJD型PDC钻头,与适合PDC钻头机械剪切破岩机理的SLTIT型扭转冲击工具配合形成了"高效PDC钻头+SLTIT型扭转冲击工具"复合钻井技术,并在哈山3井火成岩地层取得了较好的应用效果。现场应用发现,"311.1mm PK6245MJD型PDC钻头+SLTIT型扭转冲击工具"一次入井连续工作649h,单趟钻进尺457.50m,平均机械钻速1.0m/h,行程钻速0.7m/h,与相邻上部火成岩井段相比,至少节约了11趟起下钻的时间与钻头费用;同时井斜角由入井前的4.2°(井深2 882.00m)降至1.2°(井深3 310.00m),纠斜效果明显。现场应用表明,"311.1mm PK6245MJD型PDC钻头+SLTIT型扭转冲击工具"复合钻井技术是实现准噶尔盆地火成岩地层优快钻井的一种有效技术手段。

A drilling technique combining PDC bit and torsional impact tool has been developed and applied in drilling through the igneous rocks of Junggar Basin w hich solves the technical difficulties such as high hard-ness ,poor drillability and serious well deviation ,etc in drilling through igneous rock formation .In view of the li-thologic characteristics and technical difficulties of igneous rocks ,PK6245MJD PDC bit for φ311.1 mm diame-ter borehole with strong wear resistance was developed ,which combined with SLTIT type torsional impact tool suitable for PDC’ s rock shear breaking mechanism ,forming a composite drilling technique .The technique showed effective performance in drilling igneous rocks in Well Hashan 3 .In field application ,φ311.1 mm PK6245MJD PDC bit and SLTIT type torsional impact tool reached a continuous working time of 649 h with 457.50 m of drilling footage in one trip .The ROP was 1.0 m/h ,and its roundtrip ROP was 0.7 m/h .Com-pared with the drilling situation of adjacent upper igneous rocks ,at least 11 trip times and bit cost were saved . At the same time well deviation dropped from 4.2＆#176; at 2 882 m down to 1.2＆#176; at 3 310 m .So the composite drilling technique with φ311.1 mm PK6245MJD PDC bit and SLTIT type torsional impact tool is an effective way to realize optimal and fast drilling in igneous rock formations of Junggar Basin .