The circum-Mahu depression of Junggar is a complex pressure system; its regional pressure changes greatly; conglomer-ates have grown at base of Badaowan Formation with a thicknes of 100-350 m and poor drillability, leading to low ROP and long drilling period, which greatly hinders the exploration progress in circum-Mahu area. Since 2012, according to the drilling geological characteris-tics of this block, efforts have been made to tackle the technical difficulties in drilling acceleration, and a complete set of techniques have been developed for drilling acceleration through such measures as optimization of wellbore configuration and effective PDC drill bits, using lost circulation prevention drilling fluid system and using auxiliary accelerating tools. In 20 wells to which these techniques have been applied, the average rate of penetration was 6.29 m/h, up by 63.4%; drilling period was 72.29 d, shortened by 37.2%, and downhole trouble rate were 1.13%, down by 72.9%. Field application showed that the techniques for drilling acceleration have improved the ROP, shortened the drilling period and reduced the downhole troube rate. So, the above technical measures are worth promoting.%准噶尔盆地环玛湖凹陷压力系统复杂，区域压力变化大，漏失现象严重，八道湾组底部砾岩发育，厚度100~350 m 不等，可钻性差，导致机械钻速低，钻井周期长，严重制约了环玛湖地区的勘探进程。根据该区块钻井地质特点，有针对性地开展了钻井提速技术攻关。通过优化井身结构，优选高效 PDC 钻头，优选防漏堵漏钻井液体系，运用提速辅助工具，逐步形成了适合环玛湖地区的钻井提速配套技术。现场应用的20口攻关井中，平均机械钻速达到6.29 m/h，较攻关前提高63.4%，钻井周期为72.29 d，较攻关前缩短37.2%，复杂时率为1.13%，较攻关前降低72.9%。现场应用情况表明，环玛湖地区的钻井提速配套技术提高了机械钻速，缩短了钻井周期，降低了复杂时率，可进一步推广应用。
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