ass日本风韵熟妇pics男人扒开女人屁屁桶到爽|扒开胸露出奶头亲吻视频|邻居少妇的诱惑|人人妻在线播放|日日摸夜夜摸狠狠摸婷婷|制服 丝袜 人妻|激情熟妇中文字幕|看黄色欧美特一级|日本av人妻系列|高潮对白av,丰满岳妇乱熟妇之荡,日本丰满熟妇乱又伦,日韩欧美一区二区三区在线

The traditional hydraulic system used a sliding spool to control the inlet and outlet oil ways of the hydraulic actuator at the same time, as a result that the system had high consumption, low efficiency, and was prone to cavitation under active load conditions. In order to prevent cavitation phenomenon of hydraulic cylinder under the active load condition, the anti-cavitation characteristics of four hydraulic systems were analyzed theoretically, including the traditional hydraulic system, the independent metering control system, the independent metering control system with inlet differential pressure compensation and the independent metering control system with outlet differential pressure compensation. The relationship between the opening ratio μ of inlet and outlet valves and parameters such as air separation pressure Pm and load force FL was obtained. Four hydraulic system simulation models were established, and the same load force FL, inlet valve opening K1 and other simulation parameters were set, the simulation results showed that in addition to the traditional hydraulic system, the other three independent metering control systems can avoid cavitation phenomenon by changing the opening ratio μ of inlet and outlet valves, and the independent metering control system with outlet differential pressure compensation did not need to test the load force FL. Finally, the feasibility of the simulation results was verified by the experiments.