双柱塞反馈抽油泵柱塞失效分析

双柱塞反馈式抽油泵是在改进常规抽油泵结构的基础上发展起来的一种适于高粘原油开采的特殊抽油泵。这种泵在使用中柱塞损坏相当严重，极大地影响了油井的正常生产。对失效柱塞进行了金相分析和表面形貌分析，探讨了柱塞的失效机理。指出柱塞失效的原因在于泵结构不合理、柱塞与泵筒配合间隙不合理、柱塞工作时产生偏磨以及柱塞镀铬层易脱落。认为镀铬层处理不合理是柱塞寿命低的主要原因，建议通过改进泵的结构，提高制造工艺水平及选择合理的涂层材料来提高柱塞寿命。

Failure analysis of plungers on hydraulic feedback subsurface pump

The hydraulic feedback subsurface pump with double plungers, which is developed on the basis of conventional subsurface pumps is a special pump for viscous oil recovery. The pump, plunger used to he damaged severely in operation,that influenced greatly the normal oil production . Metallographie , analysis and surface appearance analysis of the danmagedplunger are conducted, and the failure mechanism of the plungers is investigated . It is pointed out that the main causesof the plunger failule lie in the improper, structure of the pump , unreasonable clearance between the plunger and barrel,offset abrasion of plunger in operaion and chromium plating layer being apt to fall out, and the main reason of the servicelife of the plunger being low is unreasonahle processing of chromium plating layer . Sugestions for improving the scrvicelife of the plunger are put forward including reforming the structure of the pump improving the manufacturing technologyand selecting rational coating materials.