Take an empty two-liter soda bottle, wash it out, fill it with water, screw the lid on tightly and set it into your toilet tank, as far away from the flapper valve as possible.

拿一个两升的空汽水瓶，洗干净，装满水，旋紧盖子，放进马桶的水箱里，离舌形阀越远越好。

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And single screw pump in the pump itself cannot set the relief valve, can only be set up in line, increase the investment of equipment cost and installation cost.

而单螺杆泵在泵本身不能设置安全阀，只能在管路中设置，提高了设备投入成本和安装成本。

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The main valve fittings with screw lid release, pressure release valve.

将主阀盖上的配管接头螺丝松开，释放阀内压力。

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These valves use a screw type valve instead of a simple flap, and they have a pressure regulating mechanism that will vent water to the ground if the intake pressure exceeds a set level.

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