压裂泵泵头体失效分析

压裂作业技术是油气田稳定增产的重要措施,其对压裂泵的质量要求非常高。某油田作业的压裂泵发生多起泵头体交变腔开裂现象,为了研究其失效机理,采用宏观检验、力学性能测试、断口分析及有限元分析等方法对裂纹性质及萌生扩展机理进行分析。结果表明:起始断裂区位于吸入腔与柱塞腔的过渡圆弧处,在交变应力与腐蚀介质的作用下发生腐蚀疲劳开裂失效。对泵头体的设计加工等方面提出了改进建议,为预防同类压裂泵发生疲劳腐蚀提供了参考。

Failure Analysis on Head Body of Fracturing Pump

Fracturing operation technology is an important measure to increase yield of the gas field; fracturing pumps of high quality are needed. Cracks were found in the alternating cavity of some fracturing pumps which worked in the oil field. In order to find out the failure mechanism of the fracturing pump, macroscopic examination, mechanical property testing, fracture analysis and finite element analysis were carried out. The results indicate that the crack initiated at the transition arc of the cavity. The co-effect of alternate stress and corrosive media led to corrosion fatigue of the pump. At last, some suggestions about the design and processing of the pump head was put forward, providing some references for prevention of corrosion fatigue of similar fracturing pumps.