Views: 238 Author: Site Editor Publish Time: 2021-06-14 Origin: Site
Pneumatic valves are the most common fluid control equipment in industrial pipelines. They are mainly composed of pneumatic actuators and valves. The valves are driven by compressed clean air to control the flow and shut-off of pipeline media, and the execution is very fast, which is usually used for fast cutting off. Pneumatic valves are usually equipped with various valve actuator accessories, such as solenoid valves, air source treatment triples, limit switches, positioners, and control boxes to achieve local control and remote centralized control. For a two-position valve that only needs to be opened and closed, the solenoid valve is a necessary configuration. The solenoid valve can control the opening/closing of the pneumatic valve through excitation/demagnetization.
In the gas circuit (or liquid circuit), the two-position three-way electric ball valve has an air inlet (connected to the air source), an air outlet (provided to the air source of the target device), and an exhaust hole (usually installed with one muffler). The two-position five-way electric actuator valve has an air inlet (connected to the air source), a positive action outlet and a counteraction outlet (respectively provided to the target device with a positive and negative action air source), and a positive action exhaust hole and a counteracting exhaust hole (with muffler installed). For small automatic control equipment, the air pipe is generally 8-12mm industrial rubber air pipe.
In terms of electricity, the two-position three-way electric actuated valve is generally single-controlled (single coil), and the two-position five-way electrically operated valve is generally double-controlled (dual coil). The coil voltage level generally adopts DC24V, AC220V, etc. Two-position three-way solenoid valves are divided into two types: normally closed and normally open. Normally closing means that the air circuit is broken when the coil is not energized, and normally open means that the air circuit is open when the coil is not energized.
The Operation Principle of The Two-Position Three-Way Solenoid Valve
The normally closed two-position three-way solenoid valve energizes the coil and the gas circuit is connected. Once the coil is de-energized, the gas circuit will be disconnected, which is equivalent to "jog". The normally open type is just the opposite.
The Operation Principle of The Two-Position Five-Way Double Electronically Controlled Solenoid Valve
When the positive action coil is energized, the positive action air circuit is connected (the positive action air outlet has air). Even if the positive action coil is powered off, the positive action air circuit is still connected, and it will be maintained until the reaction coil is energized until. When the reaction coil is energized, the reaction gas circuit is connected (there is air in the reaction outlet), even if the reaction coil is powered off, the reaction gas circuit is still connected, and it will remain until the positive operation coil is energized. This is equivalent to "self-locking". Based on the characteristics of the two-position five-way dual electric actuated gate valve, when designing the electromechanical control circuit or programming the PLC program, the motor actuated valve coil can be operated for 1 to 2 seconds, so as to protect the solenoid valve coil from damage.
The pneumatic actuator uses compressed air as the power source, converts the input control signal into a pneumatic signal, and adds it to the air actuator to drive the valve to achieve continuous adjustment or switching. The pneumatic control valve can be equipped with various accessories to achieve multiple control functions. to meet the various special requirements of the control system for pneumatic control valves. In other words, the accessories can make the function of the pneumatic control valve more perfect, more reasonable, and more complete.
