压裂泵阀箱疲劳寿命影响因素的研究

对国产某型号140 MPa压裂泵阀箱裂纹的断口进行分析,研究表明阀箱裂纹断口呈解理断裂形貌特征,疲劳辉纹在解理面上以脆性方式扩展,阀箱工作时较高的周向应力是引起疲劳开裂的主要原因。在此基础上,运用有限元软件开展了自增强技术、表面加工精度、表面强化处理工艺以及材料选择对阀箱疲劳寿命的影响规律研究。研究结果表明,以上方法均可以延长阀箱的疲劳寿命,但自增强技术是延长阀箱疲劳寿命最有效和最经济的方法,可有效延长疲劳寿命最长达7倍左右,在实施工艺上可选用静液压法和炮轰法,炮轰法工艺程序简单,建议采用该法进行自增强处理。

Research on the Influencing Factors of Fatigue Life of Fracture Pump Valve Chamber

An analysis of the crack fracture of the valve chamber of a certain type of 140 MPa fracture pump was conducted.The research findings show that the crack fracture is characterized by a kind of cleavage fracture morphology.The fatigue striations expand on the cleavage surface in the mode of brittleness.The relatively high circumferential stress of the valve chamber in operation is the main reason for fatigue cracking.On the basis of this the finite element software was used to conduct the research on the autofrettage technology,the technology of surface processing precision and surface reinforcing treatment and the law of the effect of material selection on the fatigue life of valve chamber.The research findings show that the above methods can improve the life of valve chamber.But the autofrettage technology is the most effective and economic method.It can improve the fatigue life of valve chamber by a minimum of seven times.The hydrostatic method and the explosive method can be selected in the technological implementation.The process of the explosive method is simple,which is recommended to be adopted to conduct the autofrettage.