旋冲钻井技术在川西硬地层的应用

Application of rotary percussion drilling technology in hard formation of western Sichuan

川西地区深层天然气资源丰富,是中国石化增储上产的重点区块。沙溪庙组—须家河组岩石致密,可钻性差,机械钻速慢、钻井周期长是该地区深井钻井的首要难题。针对此问题,开展了旋冲钻井技术先导试验。通过现场应用和工具的改进、完善,在钻井液密度为2.25 g/cm3的条件下,旋冲钻井的平均机械钻速比同地层PDC钻头提高26%,成为川西硬地层钻井提速的又一重要手段。

The deep gas in western Sichuan is rich in resources and is the major block to increase production for SINOPEC.The Shaximiao Formation to Xujiahe Formation rocks are dense and have poor drillability.Slow drilling speed and long cycle are the primary problems of deep drilling in this area.To solve this problem,the pilot test for rotary percussion drilling is conducted.Through field application and tool improvement,and under the condition of drilling fluid density of 2.25 g/cm3,average penetration rate increases 26% compared with PDC drilling rate in the same formation,which becomes an important means for increasing the drilling speed of hard formation.