SEAL PERFORMANCE ANALYSIS OF FRACTURING PUMP V-SHAPED COMBINATION PLUNGER BASED ON FLUID PRESSURE PENETRATION

The fracturing pump plunger seal pair is one of the components most prone to failure at the hydraulic end of the fracturing pump due to its long-term operation under variable load，reciprocal friction and high pressure, and acidic fracturing fluid. To study the influence of interference magnitude, medium pressure, etc.on the sealing performance of V-shaped sealing ring, the assembly process of V-shaped sealing ring was simulated by using automatic shrinkage fit, the actual fluid pressure action condition of the V-shaped sealing ring was simulated based on fluid pressure penetration, and the finite element model of V-shaped sealing ring was established. Under quasi-static and dynamic sealing, the maximum Mises stress and the variation law of contact pressure of the V-shaped sealing ring were analyzed. A two-stage differential pressure plunger seal structure was proposed, and the sealing performance analysis of the structure was carried out.The results show that the maximum contact pressure of the seals all appear in the V-shaped sealing ring near the high-pressure fluid side, and the maximum stress is mainly in the lip and shoulder of the V-shaped sealing ring in contact with the support ring and press ring, the V-shaped sealing ring is more likely to fail on the side in contact with the plunger. The use of two-stage differential pressure plunger seal can effectively reduce the Mises stress, shear stress, and friction between the V-shaped sealing ring and the plunger, which can extend the working life of the fracturing pump plunger seal and improve the reliability and economy of the fracturing operation.