长南工区钻井提速难点认识与实践

Understanding of Difficulties in Drilling Speed Increasing in Changnan Work Area

摘要:

长南工区属于鄂尔多斯盆地中部、南部，主要分布在安塞、延安、志丹、高家沟等地区，地质构造属于鄂尔多斯盆地伊陕斜坡构造。该区地表开始为新生界第四系黄土层，黄土高原丘陵沟壑区，表层具有节理发育、结构松散、渗透性强等特点，有垂直方向的空洞，漏失不易控制且破坏地层的胶结强度，促进漏失加剧。以下地层从中生界到古生界，地层古老，富含砂砾岩和石英砂岩，研磨性强，可钻性差，区域差异较大。针对该工区钻井技术难点，制定了详细对策，表层抑制井漏和堵漏、优选钻井液体系提高机械钻速，优选钻头系列，预防减少钻具失效等。通过应用实施，取得了明显效果，区块钻井速度大幅提高，初步形成了一套适合该区的钻井综合提速技术。

Abstract:

According to the drilling difficulties of surface joint development, loose structure and strong permeability; rich sandy conglomerate and quartz sandstone, good abrasiveness and weak drillability as well as regional difference, the detailed countermeasures were made to control seepage, optimize drilling fluid system and bit system, improve penetration rate and prevent the failure of bottom hole assembly. The block drilling speed is largely improved in the application and implementation, and a set of comprehensive drilling speed increasing technique suitable to Changnan block preliminarily formed.