压裂泵泵头体裂纹原因分析及应对措施

Cause analysis and counter measure of fracturing pump head crack

材质为38CrNi2MoVA钢的压裂泵泵头体,在使用仅30 h即出现裂纹。通过金相、宏观断口、化学成分分析、力学性能测试、扫描电镜分析等理化试验,对该泵头体裂纹原因进行了分析。结果表明,该38CrNi2MoVA钢泵头体化学成分中的C、Ni及强度和冲击韧性均低于技术要求,且泵头体内盐酸的强腐蚀作用,导致泵头体发生腐蚀疲劳裂纹。对泵头体内壁进行表面防腐渗氮处理及严控生产工艺,可预防裂纹的发生。

There was a crack in 38CrNi2MoVA steel fracturing pump head after used for only 30 h.The crack reason was analyzed by metallographic , macroscope fractographic and chemical composition analyses , mechanical properties test , scanning electronic microscope (SEM) inspection and so forth.The results show that the content of C and Ni , strength and toughness of the 38CrNi2MoVA steel fracturing pump head are lower than the the technical requirements , and pump head corroded by hydrochloric acid , all that lead to corrosion fatigue cracks of the pump head .Surface nitriding for in side wall of pump head and strict control of production proces can prevent the pump head from cracking .