Corrosion crack's propagation analysis and fatigue life prediction of the cylinder of 6000HP hydraulic fracturing pump

The fracturing pump, the key equipment for hydrofracturing operation, is characterized by its short and uncertain service life. Firstly, the crack propagation cause on the crossbore of the fluid cylinder was analyzed macroscopically and microscopically. Then, the fatigue crack expansion rate of 17-4PH steel in corrosion was measured experimentally and applied to finite element modeling analysis. It is shown that the crack growth rate of the fluid cylinder is 6.39 times faster in corrosion than that in air. The shape and direction of the crack initiation mainly affect the stress intensity factor range of the crack front during the early crack propagation of the fracturing pump fluid cylinder. The fatigue life of the fluid cylinder is greatly affected by the cyclic alternating load. This manuscript helps to gain insight into the crack propagation mechanism and predict the crack propagation fatigue life of the fracturing pump after crack initiation.