Electromagnetic valve's classification
Electromagnetic valve from principle is divided into three categories, namely: straight moving type, distribution straight moving type, pilot operated.
1) distribution direct-acting electromagnetic valve
It is a direct acting and pilot operated theory combined, when the inlet and outlet no pressure difference, after electrify, electric magnetic direct pilot small valve and the main valve closing member in turn upward mention, the valve open; When the inlet and outlet to startup pressure difference, after electrify, electric magnetic direct pilot small valve and the main valve closed software in turn upward mention, the valve open; When the inlet and outlet to start differential pressure, electricity, electric magnetic pilot small valve, the main valve inferior vena pressure rise, cavity pressure drop, and then the use of differential pressure the main valve upward push, power off, pilot valve use spring force or medium pressure promote close parts, move, valve closes. Its characteristic is in the zero differential pressure or vacuum and high pressure can also be reliable action, but power is larger, requirements must be installed horizontally.
(2) pilot operated electromagnetic valve
Electricity, electromagnetic force the pilot hole open, chamber pressure drops rapidly, in a closed around on the formation of low high differential pressure, fluid pressure promote shut down a move up and with the valve open; When power disconnected, the spring force the pilot hole closed, population pressure through the bypass hole quickly chamber in close valve a low forms around the high differential pressure, flow
Body pressure promote shut down a move, close the valve. Its characteristic is fluid pressure range limit is higher, can be arbitrary installation (need to customize) but must satisfy the fluid pressure differential conditions.
(3) direct-acting electromagnetic valve
Electricity, electromagnetic coil produce electromagnetic force the closing member from a seat, the valve open; When power disconnected, the electric magnetic disappear, spring to close a pressure in the seat. The valve closed. Its characteristic is in vacuum, negative pressure, zero pressure can work normally; But size generally not more than 25 ram.
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