等壁厚螺杆钻具研制与现场试验

Development and Field Experiment on PDM with Uniform Wall Thickness

等壁厚螺杆钻具是近年来研制成功的一种新型螺杆钻具,具有单级密封压力高、转速低、扭矩大、曲率半径小、使用寿命长、耐高温和使用更加安全可靠等技术优势,适合在常规生产井、深井、斜井和定向井中使用,但国内刚处于试验研究阶段。在介绍等壁厚螺杆钻具国内外发展现状、基本结构与设计要点的基础上,指出了等壁厚螺杆的技术特点及与常规螺杆的主要区别,并在2个区块、相同井型进行了2种不同形式螺杆钻具的应用试验。现场数据分析表明,等壁厚螺杆钻具在不维修情况下,累计下井使用时间平均193h,比常规螺杆提高40%以上,机械钻速提高22%。等壁厚螺杆钻具的使用寿命比常规螺杆钻具长,且能有效提高机械钻速、缩短建井周期,可以推广应用。

The positive displacement motor（PDM） with uniform wall thickness is a new drilling tool developed in recent years,with many technical advantages,such as single high pressure seal,low rotary speed,high torque,short radius of curvature,long service life,thermostable and safe to use,etc,suitable for conventional production well,deep well,inclined well and directional well.On the basis of current development,basic structure and designing principles of PDM at home and abroad,the paper points out the technical characteristics and its main differences compared with conventional PDM.The application and experiments in two blocks in same wells were conducted by two different PDM tools.The on-site data analysis indicates that,by using the PDM with the same wall thickness,the average downhole service time is 193 hours,and single downhole service time is 40% more than conventional PDM,the rate of penetration could be increased by 22%,and the build-up time shortened effectively.