Meanwhile, the flap valve can be used to adjust weight, springtension and the bottom outlet valve flap valve opening size to determine the pressure and open and close time.
同时，可以利用调整阀瓣的自重、弹簧的弹力以及阀瓣的底孔大小来确定阀门的开启压力和启闭时间。
2
So less water means lower pressure. It does this by opening an internal valve based on the system pressure and the springtension set on the valve.