抽油杆局部阻力偏磨机理及防治

Side Attrition Mechanism and Prevention of Local Resistance of Pumping Rods

抽油杆偏磨的因素很多,如油井结蜡、出砂、井斜、套管变形和管杆腐蚀等,但对于不同的油田、不同的区块,导致抽油杆偏磨的原因不尽相同。通过调查杏十二～十三区抽油杆偏磨情况,该区抽油杆偏磨井主要因素集中在低沉没度、高含水,抽汲参数相对较高的正常抽油机井,下冲程一般存在较强的振动载荷,其偏磨井段深度一般大于800m。在分析杏十二～十三区偏磨井历年生产数据和作业数据基础上,结合抽油杆局部阻力理论计算和现场液击试验得出杏十二～十三区抽油杆偏磨主要是因高含水、低沉没度导致抽油杆柱下行的局部阻力增加造成的。根据该原因制定并实施调整抽没参数,保证抽油机井合理的沉没度预防该区抽油杆偏磨的措施,实践证明措施有效。

There are lots of factors of pumping rod side attrition, for example, wax deposit, sanding, well deflection, casing deformation, and tube and rod corrosion, etc. , but there are the different factors to different oilfields. Through researching the side attrition of pumping rods in Xing12-13 area, the main factors of the area are low submergence depth, high water-cut; the normal pumping wells that the swabbing parameters are relative higher, the low stroke commonly exist the stronger vibration loads, the side attrition depth is commonly more deeper than 800 m. On the basis of analyzing the producing and operating data of side attrition wells of Xingl2-13 area, combining with theoretical calculation and on-the-spot liquid-sroke testing of local resistance of pumping rods, it is obtained that the main factor of side attrition of pumping rods in Xingl2-13 area is local resistance increasing of pumping rods going down of causing by high water-cut and lower submergence depth. According to this factor, the swabbing parameters were adjusted to guareatee reasonable submergence depth for preventing pumping rods from side attrition, the practice verifies that the measures are effective.