杨税务潜山超深超高温井安全优快钻井技术

为解决冀中地区廊固凹陷潜山构造带超深超高温潜山油气井在钻进过程中遇到漏、喷、卡、机械钻速低及轨迹控制困难等问题，在分析已完井钻井难点，调研国内超深井钻井提速技术基础上，采取了优化井身结构，简化井眼轨道，针对地层特点设计孕镶齿PDC钻头并优选钻具组合及钻井参数，研制220 ℃低固相抗高温钻井液，研发200 ℃全金属随钻测量井下脉冲发生器等措施。现场应用结果表明:优化后的井身结构与井眼轨道更易于井眼轨迹调整，使用高效PDC钻头与辅助提速、破岩工具相配合，平均机械钻速较之前提高了1~2倍，低固相抗高温钻井液在200 ℃性能稳定，满足安全施工需求，随钻测量全金属脉冲发生器在井温175 ℃条件下可持续工作超过200 h。该区块平均钻井周期较前期完井缩短了50%，最深完钻井深6 455 m、实测井底静止温度207 ℃。所采取的安全、优、快钻井技术可对后期超深、超高温井钻井提供借鉴与参考。

Optimized,safe and fast drilling technologies used in the ultra deep and high temperature wells in Yangshuiwu buried hill

In the drilling process of oil and gas wells in the ultra deep and ultra high temperature buried hill of buried-hill structural belt in Langgu sag of central Hebei, several problems are encountered, including leakage, blowout, sticking, low rate of penetration (ROP) and difficult trajectory control. In order to solve these problems, this paper firstly analyzed the drilling difficulties of drilled wells and investigated domestic ROP improvement technologies of ultra deep wells. Then, a series of measures were taken. For example, the casing program was optimized and the well track was simplified. Based on the stratigraphic characteristics, impregnated-tooth PDC bit was designed, and bottom hole assembly (BHA) and drilling parameters were optimized. In addition, low solid and high temperature (220 ℃) drilling fluid was prepared, and 200 ℃ all-metal downhole pulser for measurement while drilling was developed. The field application results show that the optimized casing program and well track are convenient for the adjustment of wellbore trajectory. Owing to the application of efficient PDC bit, combined with the supporting ROP improvement and rock breaking tools, the average ROP is increased by 1-2 times. The performance of low solid and high temperature drilling fluid is stable under the temperature of 200 ℃, which can meet the requirements of safe construction. The all-metal downhole pulser for measurement while drilling can work continuously for over 200 h under the well temperature of 175 ℃. The average drilling cycle is 50% shorter than that in the early stage, the maximum total well depth is 6 455 m and the measured bottom hole static temperature is 207 ℃ in this block. In conclusion, the optimized, safe and fast drilling technologies adopted here can provide references for the drilling of ultra deep and ultra high temperature wells in the late stage.