高效切割一体多刀水力割刀研究

海上油田修井作业时需要使用水力割刀对防砂管柱进行多次切割打捞作业。切割作业时常规水力割刀只能切割一次,需要多次起下管柱更换割刀,作业效率低。针对此问题,分析了传统水力割刀结构、工作原理以及提高割刀切割能力方法,采用增加割刀数量方法,研制了一种一体多刀水力割刀,并对其结构和工作原理进行了介绍。结合割刀换向原理,建立了换向机构几何模型,分析计算其节流压力符合作业要求。试验井测试结果表明:一体多刀水力割刀可根据泥浆循环流量,选择性张开割刀,割刀张开所需流量稳定,割刀张开顺序有序;单趟钻可至少切割防砂管柱三次,降低了切割防砂管柱时起下钻次数,提高了切割效率。研究结果可为水力割刀研究提供新的设计思路。

Research on highly efficient hydraulic cutter with multi-cutter

During workover operation in offshore oilfield,hydraulic cutter was required to cut and fish sand control string several times.In cutting operation,the conventional hydraulic cutter could only cut once,and the cutter was needed to be replaced by tripping the pipe string several times,so the operation efficiency was low.Aiming at this problem,the structure and working principle of the conventional hydraulic cutter and the methods to improve the cutting ability of the cutter was analyzed.By increasing the number of cutters,a type of hydraulic cutter with multi-cutter was developed,and its structure and working principle was introduced.Based on the principle of cutter reversing,the geometric model of reversing mechanism was established.The throttle pressure was analyzed and calculated to meet the operation requirements.The test of test wells shows that based on slurry circulation rate,the cutter of hydraulic cutter with multi-cutter could spread out selectively.The press of cutter spreading out is steady.The hydraulic cutter with multi-cutter could cut off the sand control string three times in one-trip at least,therefore decreasing the times of trip-out and going down and improving the cutting efficiency.The research can provide one new design idea to study and design the hydraulic cutter.