ZXG6-1井88.9 mm特殊螺纹接头油管脱扣原因分析

摘要

对ZXG6-1井在试油期间88.9 mm特殊螺纹接头油管座封打压作业过程中发生的脱扣事故进行了调查研究，对脱扣接箍几何尺寸和螺纹接头参数进行了测量和分析，认为在座封打压作业过程中油管柱承受内压和震动等载荷后，油管柱从油管接头薄弱环节首先发生松动，最终发生了脱扣。油管脱扣原因是其接头工厂端上扣扭矩不足。对该批油管工厂上扣扭矩统计分析发现，该批油管中有少量油管上扣扭矩不足。为防止油管在使用过程中再次发生脱扣事故，对如何改进油管上扣质量提出了改进建议，对如何使用该批油管提出了具体措施。%This paper gives an investigation on pullout accident of 88. 9mm tubing with premium connection in the packer and seat sealing down assignments in ZXG6-1 Well, and gages and analyses on the dimension and thread parameter of the pulled out coupling. It is consid-ered that the tubing string joint was pulled out because of the joint being loosed from weak position due to internal pressure and vibration load borne on the tubing string during packer and seat sealing down assignments. The cause of tubing joint being pulled out is that its make-up torque was not enough. There were a few tubing with not enough make-up torque in this batch of tubing per statistical analysis on the tub-ing make-up torque record in the mill. In order to prevent tubing from being pulled out, it is suggested that the tubing make-up quality should be improved, and some measures are put forward for using this batch of tubing.