Working principle and function of solenoid valve
Solenoid valve is a kind of industrial equipment controlled by electromagnetism, which is particularly common in industrial machine control and industrial valve. It can control the direction, flow, speed and other parameters of the medium, so as to control the valve switch.
1、Direct acting solenoid valve
Principle: When the normally closed type is energized, the solenoid coil generates electromagnetic force to lift the open part from the valve seat, and the valve opens; When the power is cut off, the electromagnetic force disappears, the spring presses the open part on the valve seat, and the valve opens.
Features: It can work normally under vacuum, negative pressure and zero pressure, and the diameter generally does not exceed 25mm.
2、Step-by-step direct-acting solenoid valve
Principle: when the inlet and outlet reach the starting pressure difference, the electromagnetic force pilot small valve, the lower chamber pressure of the main valve rises, the upper chamber pressure drops, and the main valve is pushed upward by the pressure difference; When the power is cut off, the pilot valve uses spring force or medium pressure to push the closing part and move downward to close the valve.
Features: It can also operate at zero differential pressure, vacuum and high pressure, but the power is large and must be installed horizontally.
3、Indirect pilot solenoid valve
Principe : lorsqu'elle est alimentée, la force électromagnétique ouvre le trou pilote et la pression dans la chambre supérieure chute rapidement, formant une différence de pression haute et basse autour de la partie ouverte. La pression du fluide pousse la partie ouverte vers le haut et la vanne s'ouvre ; Lorsque l'alimentation est coupée, la force du ressort ouvre le trou pilote et la pression d'entrée forme rapidement une différence de pression inférieure et supérieure autour des pièces de fermeture de la vanne à travers le trou de dérivation. La pression du fluide pousse les parties ouvertes vers le bas pour ouvrir la vanne.
Caractéristiques: petit volume, faible puissance, limite supérieure élevée de la plage de pression du fluide, peut être installé à volonté, mais doit respecter les conditions de différence de pression du fluide.
