The Analysis In Dynamic Characteristics for Check Valve of Water Micro-Piston Pump

Micro-piston pumps are widely used in many aspect like quantitative transportation of petroleum, chemical industry, medicine, biology , water treatment , etc. This is especially for high pressure and small flow accurate transportation, valve ball lag closure has an important impact on flow accuracy. In this paper, the dynamic model of check ball valve for conveying water viscosity medium is established, the second-order non-linear equation is solved numerically, and the dynamic characteristics of the outlet valve are calculated for a piston pump driven by crank mechanism. The results show that the self-weight check ball valve converges at different crank speeds, but exists a certain closing lag. When the minimum critical spring force is 60% of the valve’s selfweight, the ball valves are closed without delay. The opening displacement of the valve ball fluctuates. There is a large acceleration impact on the opening of the valve ball. When the valve ball is close to closing, it has obvious acceleration. The rising acceleration with spring occurs ahead of time, which can avoid the closing lag. It is necessary to calculate the actual pump to ensure the accuracy of pump flow.