库车前陆盆地超深井全井筒提速技术  

Whole well ROP enhancement technology for super-deep wells in kuqa foreland basin

作　　者：滕学清[1,2] 陈勉[1] 杨沛[2] 李宁[2] 周波[2] 

机构地区：[1]中国石油大学(北京)石油与天然气工程学院 [2]中国石油塔里木油田公司油气工程研究院

出　　处：《中国石油勘探》2016年第1期76-88,共13页China Petroleum Exploration

摘　　要：库车前陆盆地90％油气资源集中在深层和超深层，但该区块地质条件复杂，油气埋藏深（5000～8000m）、温度高（100～178℃）、压力大（100～140MPa）。上部地层为高陡构造，普遍发育巨厚砾石层，防斜打快矛盾突出；中下部大段复合盐膏层、高压盐水层（2．4～2．6g／cm2）和低压漏失层并存，压力系统多变，作业风险高；储层岩石研磨性高，带来了机械钻速低等一系列技术难题。针对上部高陡构造钻井问题，引进垂直钻井系统，改进控制系统原件，建立了垂直钻井标准作业程序，同时基于岩石可钻性分析和垂直钻井系统受力特点，建立砾石层钻头优选原则：（1）在整个保径部分上必须镶有侧向切削齿，并且保径部分越短，越适合造斜和降斜；（2）外锥部位越短（并且有侧向切削能力），越适合造斜和降斜；（3）内锥的形态越浅，越适合造斜和降斜。针对复合盐膏岩地层问题，通过室内实验优化油基钻井液水油配比，将油水比从引进时的95：5降低至80：20，大幅降低成本，同时建立油基钻井液中转处理站，配套废弃物处理技术，对油基钻井液进行回收利用，一方面降低成本，另一方面保证废弃物达到环保要求。针对储层地层研磨性强、可钻性差的特点，引进国外涡轮钻具和ONYX360钻头并开展现场试验，孕镶金刚石钻头来对抗岩石的高研磨性，ONYX360钻头是在普通金刚石钻头研磨性要求高的地方安装可以旋转的金刚石复合片，保证钻头的切削能力。在以上关键技术的组合下，最终形成库车前陆盆地超深井全井筒提速技术，克深一大北区块钻井周期由2011年的456．6天（平均井深6690m）降到2014年的267天（平均井深6485m）。Around 90% of hydrocarbon resources of the Kuqa foreland basin are mainly distributed in deep and ultra-deep layers, but this area has very complex geologic conditions, very deep buried hydrocarbon reservoirs （5000-8000 m）, high reservoir temperatures （100-178 C ） and high formation pressures （100-140 MPa）. The upper strata is a high-steep structure, generally developing a widespread and thick gravel layer, with apparent prominent contradiction in controlling deviation and increasing ROP （Rate of Penetration）. The middle-lower strata have coexisting thick composite salt-gypsum layer, high-pressure saline layer （2.4-2.6 g/cm3） and low-pressure leakage layer, with variable pressure systems and high operation risk. The reservoir rocks have high abrasiveness, leading to a series of technical issues （such as low ROP performance, etc.）. Aiming at the drilling issues in the upper high-steep structure, Tarim Oilfield Company imported the vertical drilling system, improved components of the controlling system, and established standard operating procedures for vertical drilling in this oilfield; moreover, based on the analysis of rock drillability and characteristics of vertical drilling system＇s forced state, Tarim Oilfield Company set up the principle for optimizing drill bits in gravel layers： （1） Lateral cutting teeth must be inlaid in the whole diameter part, and the shorter is the gauge portion, the more suitable for deflecting and drop angle; （2） The shorter is the outer cone part （with lateral cutting ability）, the more suitable for deflecting and drop angle; （3） The shallower is the cone form, the easier to meet the demand of increasing deviation and dropping angle. Aiming at the drilling issues in salt-gypsum layers, Tarim Oilfield Company greatly reduced the cost by optimizing oil-water ratio ofoil base mud （reduced the oil-water ratio from 95 ： 5 to 80 ： 20）, simultaneously building up oil base mud recycling and waste treatment system,forming oil base drilling

关 键 词：库车前陆盆地 超深井 高陡构造 提速 垂直钻井 油基钻井液 

分 类 号：TE242[石油与天然气工程—油气井工程]