“垂直钻井工具+等壁厚螺杆”提速钻具组合先导性试验

为有效解决库车山前井因高陡构造、高含砾石及地层各向异性导致的井斜控制难、钻头涡动及钻具黏滑问题，塔里木油田在克深A井盐上高含砾石地层康村组、吉迪克组应用了“垂直钻井工具+等壁厚螺杆”提速钻具组合。优选了适用于库车山前地区的输出功率高、性能稳定、处理复杂能力强的螺杆钻具，并通过钻柱力学及水力学优化设计解决了与垂直钻井工具的配套问题，实钻过程可用钻压高、扭矩平稳、机械钻速快，能够有效控制井斜并改善钻头涡动、钻具黏滑等非正常钻进状态，达到了解放钻压、保护钻头和提高破岩效率的目的，相比邻井同层位同井段机械钻速、单趟钻进尺分别有75%~262%、51%~134%的提高。验证了“垂直钻井工具+等壁厚螺杆”钻具组合在库车山前高陡含砾地层的提速应用可行性，可在库车山前井盐上地层规模推广使用。

Pilot test on the ROP-improvement BHA of vertical drilling tool & screw rod with equal wall thickness: A case study on Well Keshen A in the high-steep structure of Kuqa piedmont area

The wells in Kuqa piedmont area suffer the problems of difficult hole deviation control, bit swirling and drilling tool stick-slip caused by high-steep structure, high conglomerate content and formation anisotropy. In order to solve these problems effectively, Tarim Oilfield applies the bottom hole assembly (BHA) of “vertical drilling tool + screw rod with equal wall thickness” for rate of penetration (ROP) improvement in Kangcun Formation and Jidike Formation of supra-salt formation with high conglomerate content in Well A of Keshen . The positive displacement drill with high output power, stable performance and strong complex situation treatment ability suitable for Kuqa piedmont area is selected, and its matching problem with the vertical drilling tool is solved based on the optimization design of drill string mechanics and hydromechanics. In the process of actual drilling, the available weight on bit (WOB) is high, the torque is stable and the ROP is high, so hole deviation is controlled effectively and abnormal drilling states are improved, such as bit swirling and drilling tool stick-slip, so as to reach the target of WOB liberation, bit protection and rock breaking efficiency improvement. Compared with the same hole section in the same horizon of its neighboring well, its ROP and single-trip drilling footage are increased by 75%-262% and 51%-134%, respectively. It is verified that the BHA of “vertical drilling tool + screw rod with equal wall thickness” is feasible to the ROP improvement in high-steep conglomeratic formation of Kuqa piedmont area, so it can be applied and popularized in the supra-salt formation in the wells of Kuqa piedmont area in a large scale.