KXS203井口设备偏磨原因分析

KXS203井在钻井过程中井架底座基础非均匀下沉，套管头和防磨套严重偏磨，随后套管柱试压发生了泄漏。为了搞清该井井口设备偏磨原因，防止此类事故再次发生，对该井井口设备和钻杆磨损情况进行了研究，对井架基础下沉造成的井口偏心程度进行了分析计算，并从钻杆接头与井口设备尺寸匹配、井口偏心、防磨套及顶丝性能、钻柱旋转和起下钻、钻柱转速等方面对井口设备偏磨影响因素进行了分析。认为井口设备与井架基础下沉、钻杆接头与井口设备尺寸匹配、井口偏心、防磨套及顶丝性能、钻柱旋转和起下钻、钻柱转速等对井口设备偏磨等有关，但该井井口设备偏磨主要原因与井口偏心和防磨套失效有关。提出了防止井口设备偏磨的建议。

Causes analysis of wellhead equipment eccentric wear in Well KXS203

Due to the derrick substructure non-uniform subsidence of Well KXS203, casing head and wear bushing of this well were severely worn during drilling, and then casing string leaked later in pressure testing. In order to figure out the cause of wellhead equipment worn, and to prevent this kind of accident from happening again, the paper gives an investigation on the wearing condition of wellhead equipment and drill pipe, and calculates the eccentric wellhead degree due to derrick foundation settlement, and analyzes the influence of dimension match between drill pipe tool joint and wellhead equipment, wellhead eccentricity, performance of wear bushing and jacking screw, rotation of the drill string, drilling trip, and rotational speed of the drill string on wellhead equipment eccentric wear. It is considered that the wellhead worn is related to all above aspects, but the wear of wellhead in this well is mainly because of the wellhead eccentricity and wearing bush failure. Some measures are suggested to prevent well head equipment from wear.