高压压裂泵排出管汇振动特性与减振分析OA

The fracturing technology has characteristics of multiple repetitions of fracturing,large liquid-injection volume and high operating pressure.The discharge manifolds of high-pressure fracturing pumps are prone to fatigue failure under the flow pulsation excitation induced by internal fracturing fluid.To clarify the vibration law of the discharge manifold in the high-pressure fracturing pump and develop vibration reduction schemes,the velocity inlet boundary condition was defined based on the instantaneous velocity equation of discharged fracturing fluid for a five-cylinder fracturing pump,and the fluid-structure coupling simulation of the discharge manifold was completed.For the discharge manifold in the states of no support,surface-A support,surface-B support,and dual-surface support of A and B,the pre-stressed modal simulation analysis was carried out first,followed by field vibration tests under actual fracturing conditions to verify the simulation results.The results showed that:applying surface-A support could significantly improve the pre-stressed modal natural frequencies of the discharge manifold,effectively avoiding the excitation frequency of fracturing operation and eliminating resonance risk.Compared with surface-B support and dual-surface support of A and B,the surface-A support featured convenient disassembly,assembly and maintenance,and it could significantly reduce the vibration amplitude of the discharge manifold,thereby lowering the fatigue failure risk.The double elbow area experienced intense vibration responses due to the combined effect of fluid turning and flow pulsation.Additionally,due to insufficient constraints and low structural stiffness,this area became a failure-prone weak position of the discharge manifold.It was recommended to add local support structures.The research results can provide theoretical support and practical reference for the vibration reduction optimization of discharge manifolds of high-pressure fracturing pumps in oil fields.