Both the pneumatic valve and the solenoid valve are widely used in various industrial areas to control medium flowing through or cutoff in pipelines. Are there any distinctions between them? Let's continue and look for some differences.
A pneumatic valve uses compressed air to control the diaphragm, bellows, or cylinder, and by controlling the diaphragm, bellows, or cylinder, the valve stem is pushed to close and open the valve core. The diaphragm pneumatic valve is a multi-port air intake valve. It uses a spring to reset and a diaphragm to move the valve stem, and the valve stem connects to the valve core to open or close the valve. The bellows pneumatic valve has a single air intake port. The cylinder-type pneumatic valve can have a single or double air intake port. The cylinder's push rod connects to the stem, and the stem connects to the spool to open or close it.
There are two types of pneumatic valves: air-closed and air-opened. Pneumatic valves are safer than solenoid valves in flammable and explosive environments because there is no risk of accidental ignition. Pneumatic valves that control higher fluid pressures or have a larger diameter typically have pilot valves inside that can amplify the force of the on-off valve.
A solenoid valve is a device that opens and closes liquid, gas, and steam valves by energizing and de-energizing the coil. The solenoid valve moves when the power is turned on. After the power is turned off, the spring or fluid pressure inside is used to reset. The direction of fluid is usually marked on the solenoid valve, and it cannot be installed backward. Solenoid valves are used in small diameter pipelines because they close and open quickly.
Solenoid valves are classified into two types: normally open (the valve closes when the power is turned on) and normally closed (the valve open when power on). This is primarily considered from a safety standpoint. When the power is suddenly cut off in some production processes, it is necessary to turn off the medium (such as gas), whereas in other control processes, it may be necessary to turn on after the power is suddenly cut off. It uses both AC and DC power(12vdc and 24vdc) supplies. Solenoid valves have a wide range of applications in industrial automation and household appliances (washing machines, air conditioners, water heaters, IC water meters).
Originally written by https://allaboutsolenoidvalve.blogspot.com/