银参4井钻井设计与施工

Drilling Design and Construction of Well Yincan 4

摘要:

银参4井是中石化在银川地区的第一口参数井，设计井深为4300 m，完钻井深4124.23 m，钻探目的是了解银川盆地地层层序及清水营组烃源岩发育情况。针对该井在钻井过程中存在的上部地层胶结疏松易垮塌、干河沟组在砾石层易憋跳钻、清水营组地层流体侵入污染泥浆、钻遇到大段未预知的盐膏层、清水岩组泥岩存在裂缝导致钻井液漏失等复杂情况，在设计井身结构、优选水力参数时考虑了已经预知的潜在复杂因素，施工时全井大段采用直螺杆加防斜钻具组合大排量轻压吊打，有效防止了憋跳钻，避免了钻具事故，取得了较高的钻井速度，控制了良好的井身质量，探索了适用该区盐膏层段的钻井液体系，并且创造了该区块φ444.5 mm钻头机械钻速最高纪录（39.09 m/h）。

Abstract:

Well Yincan 4 is the first parameter well for Sinopec in Yinchuan District, the purpose of drilling is to investigate the stratigraphic sequence of Yinchuan basin and the development of Qingshuiying formation hydrocarbon source rock. According to the complicated conditions in drilling process, such as cementing, loose and collapsing in upper formation, bit bouncing in gravel layer of Ganhegou formation, mud pollution by intrusive fluid in Qingshuiying formation, drilling into a large section of unexpected salt gypsum layer and lost circulation of drilling fluid in mudstone fracture of Qingshuiying formation, which were considered in the design of wellbore structure and optimization of hydraulic parameters, straight screw drilling tool and inclining prevention BHA were used with large discharge and light pressure in the large section construction to effectively prevent bit bounce, high drilling speed and good well quality were achieved. The drilling fluid system suitable for the salt gypsum layer in this area is explored and the best ROP record of 39.09m/h is created with φ444.5mm bit.