淮北煤层气井井斜控制技术

WELL DEVIATION CONTROL TECHNOLOGY IN THE COALBED METHANE WELL IN HUAIBEI

淮北SN区块 4口煤层气井所处地层造斜力强 ,在这种地层钻直井 ,用常规防斜钻具和纠斜方法难以达到设计要求。采用井下动力钻具定向防斜纠斜 ,达到了最大井斜角小于等于 5°的要求。介绍了SN - 3井反方向调整井斜方位的工艺方法 ,6次调整钻具组合 ,由常规的满眼、钟摆钻具调整为动力钻具 ,并更换 1.5°弯接头和 0 .75°单弯螺杆 ,使井斜角控制在 3.5° ,方位角控制在 2 6 0°的设计指标。其它 3口井改变钻具组合后 ,机械钻速明显提高 ,由SN - 3井的 5 .36m/h提高到 11.95～ 13.46m/h ,纯钻时间由SN - 3井的 75h减少到 37.

Formation deflection tendency is distinctive in block SN of Huaibei area, and the conventional deviation control drilling assemblies and correction methods are inefficient in vertical drilling of this formation. Downhole motors are used for deviation control and correction, and it meets the requirement of maintaining the maximum inclination within 5°. Reverse direction adjustment in well SN-3 is described, which involves six drilling assembly adjustments. Pack-hole and pendulum assemblies are replaced with downhole motors, and 1.5° bent subs and 0.75° single bent screws are also changed. After adjustment, the inclination and direction are controlled within 3.5° and 260° respectively. Drilling assemblies adjustments in other three wells increase penetration rate from 5.36 m/h to 11.95 ～ 13.46 m/h, and drilling time is reduced to 37.81 h over the 75h used in well SN-3.