Air valve

The gas valve is a part of the compressor used to control the gas in and out of the cylinder. It is mainly composed of valve seat, valve disc, spring and lift limiter. The lift height or closure between the valve plate and the valve seat determines the size and airtightness of the gas passage. The spring is mainly used to push the valve plate to close, and it can also reduce the impact of the valve plate with the lift limiter when the valve plate is opened. The lift limiter can limit the lift of the valve plate and can hold the spring; the opening and closing of the valve plate is controlled by the pressure difference between the inside and outside of the cylinder and the spring force, without other driving mechanisms, so it is called an automatic valve.

The air valve is an important part of the reciprocating piston compressor, and it is also one of the easily damaged parts. Its quality directly affects the compressor's displacement, power consumption and operation reliability. When the compressor is developing towards high speed, one of the key problems that limit the increase in speed is the valve. Piston compressors generally use "automatic valves", that is, the opening and closing of the valve is realized by the pressure difference between the two sides of the valve plate, and there is no other driving mechanism.

Both the valve seat and the lift limiter are subjected to shock loads, and the valve seat also bears the gas pressure difference on both sides of the valve. The material is required to be impact resistant and have sufficient strength. The material of the valve seat and the lift limiter can be selected according to the different gas properties and the pressure difference.

The valve disc material should have the properties of high strength and good toughness. Air valve springs are generally made of carbon spring steel, alloy spring steel and stainless steel. In addition to ring valves, compressor air valves also include mesh valves, butterfly valves, orifice valves, and direct-flow valves. Its principle of action is roughly the same as that of the ring valve, but each has different characteristics.