梨树断陷页岩气水平井钻井关键技术

为解决部署在梨树断陷的首口页岩气水平井梨页1HF井存在的井壁失稳风险高、机械钻速低、固井施工难度大、井眼轨迹控制难度大等技术难题。在梨页1HF井施工过程中,通过综合应用油基钻井液、旋转导向地质导向、双凝双密度水泥浆等技术,并进行了钻头优选和钻具组合优化。施工结果表明井眼稳定,井眼轨迹平滑,水平段共完成进尺1 020 m,储层钻遇率92.7%,固井质量优秀。该井实现了安全、高效钻进,实际钻井周期22.56 d,较设计钻井周期缩短了14.94 d,平均机械钻速7.98 m/h,较设计提高了82.19%。该井良好的施工效果,可见对后续梨树断陷页岩气水平井施工具有积极的指导和借鉴作用。

Key Drilling Techniques for Shale Gas Horizontal Wellin Lishu Faulted Depression

The first shale gas horizontal well Liye 1HF deployed in the Lishu faulted depression has technical problems such as high risk of wellbore instability, low rate of penetration, difficult in cementing construction, and difficulty in wellbore trajectory control. In the construction process of the Liye 1HF well, the oil-based drilling fluid, rotary-steering geo-steering, double-condensation double-density cement slurry and other technologies were comprehensively applied, and the optimization of the drill bit and the drilling tool combination optimization were carried out. During the construction process, the wellbore was stable and the wellbore trajectory was smooth. The horizontal section had a total footage of 1020m, the reservoir drilling rate was 92.7%, and the cementing quality was excellent. The well achieves safe and efficient drilling. The actual drilling cycle is 22.56 days, which is shortened by 14.94 days compared with the designed drilling cycle, and the average rate of penetration is 7.98m/h, which is 82.19% higher than the design. The good construction effect of the well has positive guidance and reference for the subsequent construction of shale gas horizontal wells in the Lishu faulted depression.