平衡阀流量饱和特性研究与应用

Flow Saturation Characteristic of Counterbalance Valve and Application

平衡阀是一种的重要控制元件。对汽车起重机变幅平衡阀进行动力学分析,并用Matlab进行数值仿真,得到了平衡阀的流量-压差曲线族,分析不同参数对平衡阀流量饱和特性的影响,仿真结果表明,平衡阀的确存在流量饱和特性,且流量饱和特性与节流槽数量和控制压力等有关。在节流槽参数不变的情况下,节流槽数量越多,流量饱和点越大,达到饱和的压差越小。另外,流量饱和点随着控制压力的增大而增大,而达到饱和时的压差则逐渐减小。通过对平衡阀的台架试验验证了理论和仿真分析的正确性。利用研究结果改进某型起重机变幅平衡阀和变幅系统,并进行试验测试。测试结果显示,改进后的落幅流量差减少了约61%,全程落幅时间缩短了约38%,证明了研究具有工程应用价值。

Counterbalance valve is a kind of important control components. The dynamic analysis of the counterbalance valve with truck crane is researched. The flow-differential pressure curves of counterbalance valves are derived and the simulation study is performed to demonstrate the existence of the flow saturation characteristic. The impact of parameters is analyzed. The simulation results show that the flow saturation characteristic is related to the number of notches and the control pressure. The flow saturation point is larger with more number of notches. But the corresponding differential pressure at the flow saturation point is lower. In addition, the flow saturation points are directly proportional to the control pressures. While the differential pressures of the counterbalance valve at the flow saturation points are inversely proportional to the control pressures. The validity of study is verified through bench experiments. At last, a class of counterbalance valves of truck crane and corresponding system are improved based on the research and a test is finished. Test results show that the flow of boom falling decreases about 61% and entire falling time shortens 38% which prove the research results have the value of engineering application.