液压系统中污染和气穴现象是两个最重要的问题。在压力油箱上安装一个价格低廉的压力真空阀(P—V),污染和气穴现象就可以减少到最低程度。压力真空阀由压力卸荷阀芯、真空降压阀门、空气滤清器、滤口盖和滤油阀组成。当压力油箱油位下降时,真空降压阀门开启,空气经滤清器进入油箱。进入的空气使气泡体积发生变化,油位得以调节。当油箱内压力大于额定值时(通常为5—10磅/英寸~2),压力卸荷阀芯高起,把空气排放到大气中。 Pollution and cavitation in hydraulic systems are two of the most important issues. Installing a low-cost pressure vacuum valve (P-V) on the pressure tank minimizes pollution and cavitation. Pressure vacuum valve by the pressure unloading spool, vacuum pressure relief valve, air filter, filter cover and filter valve. When the pressure tank level drops, the vacuum pressure relief valve opens, the air enters the tank through the filter. Air enters the bubble volume changes, the oil level can be adjusted. When the pressure in the fuel tank is higher than the rated value (usually 5-10 lbs / in2), the pressure unloading spool rises to release the air into the atmosphere.