The bottom valve is a kind of energy-saving valve, which is generally installed at the bottom end of the underwater suction pipe of the water pump to restrict the liquid in the water pump pipe from returning to the water source, playing the function of only entering but not leaving. There are many water inlets and reinforcing ribs on the valve cover, which are not easy to be blocked, and are mainly used in pumping pipelines. The role of water channel and support. The caliber has single, double, and multi-lobe types, with flange connection and threaded connection. Other names: internal thread lifting bottom valve---bottom valve, suction valve, water filter valve, shower head; lifting bottom valve--flange bottom valve; swing bottom valve--flange swing well Bottom valve.