配流气蚀对高压柱塞泵容积效率影响的试验研究

Experimental Study on the Effect of Distribution Cavitation on Volumetric Efficiency of High Pressure Piston Pump

为减小配流冲击,高压柱塞泵的柱塞腔在过渡过程中必须通过机械闭死压缩、膨胀和减振槽引油共同作用来实现预升压和预卸压。此过程中,减振槽的两端均作用较大变化的压差,槽中的油液产生较大速度的压差流,导致出现低压区,形成气穴,气泡破裂时产生气蚀,破坏配流盘和缸体表面,大幅降低泵的容积效率。进行耐久性试验,研究配流气蚀破坏的特征和容积效率的变化。结果表明:在现有配流结构下,配流气蚀严重,耐久性试验仅开展了600 h,缸体表面已出现严重的气蚀破坏,导致泵的容积效率大幅下降。为提高泵的耐久性和提高容积效率,必须研究抗气蚀配流结构以减小配流副表面的配流气蚀破坏。

In order to reduce the impact of flow distribution,the piston cavity of high-pressure piston pump must realize pre-pressure rise and pre-pressure release through the joint action of mechanical closed compression,expansion and oil introduction of damping groove in the transition process.In this process,the two ends of the damping groove are acted on a large varying differential pressure,and the oil in the groove produces a high-speed differential pressure flow,the low-pressure areas are generated,the cavitation is formed,and the cavitation is occured when the bubble is broken,the surfaces of the valve plate and cylinder block are destroyed,and the volume efficiency of the pump is greatly reduced.The durability test was conducted,the characteristics of distribution cavitation damage and the change of volumetric efficiency were studied.The results show that under the existing distribution structure,the distribution cavitation is serious,durability test only carries out 600 h,the surface of the cylinder has appeares serious gas erosion damage,the pump volume efficiency droppes significantly.To improve the pump durability and volume efficiency,gas corrosion resistance structure must be studied to reduce the current gas erosion damage of the current subsurface.