| Solenoid Valve, TORK | | Solenoid valves are electrically operated devices to control the on/off, flow of the fluid like air, water, gas, light oil, steam, natural gas, LPG, gasoline, hot water, acid, potable water and filtered clean flowing media. | | Solenoid valves consist of main elements such as valve body, coil, diaphragm, tube and plunger. | | Working Principle of Solenoid Valves: | | a) Direct Operated: | When a solenoid valve is energized by an electrical signal, plunger of solenoid is pulled up thus it opens
or closes orifice of solenoid valve and provides the valve on-off or directional control of fluid.
Direct operated valves of actuation do not require any operating of differantial pressure for on-off function.
The sealing element is directly connected to the plunger (core) sealing of direct operated solenoid valves closed position, the sealing core is pressed on to the valve seat by the power of the spring.
When the solenoid is energised with electrical signal; the plunger is drawn in and valve opens. Orifice sizes are from 1,8mm up to 9mm. therefore max. operating pressure can be 40 bar. Working pressure changes in accordance with orifice sizes. | | b) Pilot Operated: |
TORK pilot operated solenoid valves are sealed by diaphragm on the orifice seat and plunger is pressed on the pilot seat. When coil of valve is energized; plunger is drawn thus it opens pilot orifice seat.
The upstream pressure is equal to the downstream pressure in the diaphragm before the normally closed valve is energized.
After opening pilot seat, pressure values of each side is changed hence diaphragm is moved up to bonnet of valve body. The diaphragm allows the fluid to pass the media outlet port of valve. Minimum operating pressure difference between inlet port outlet port must be 0,5 bar in order to work.
Solenoid valve shuld not be used as a check valve. If a pressure occured outlet of the solenoid valve the fluid will go back to reverse direction. If necessary; a check valve should be used after solenoid valve. | | Minimum Operated Pressure Differential: | This is the lowest differential presure, between inlet and outlet pressure values, at which the valve can reliably work.
Direct operated valves do not require a min. operated pressure.
Pilot operated valves' min. operated pressure specified in catalogue sheets is required as 0,5 bar.
Tork valves work with the following Δp presure values. | | 1.) Δp pressure value: 0,5 bar, diaphragm pilot operated types of TORK valves | | 2.) Δp pressure value: 0,3 bar, diaphragm pilot operated types of TORK valves | | 3.) Δp pressure value: 0 bar, direct acting valve, diaphragm pilot operated types of TORK valves |
Maximum Operating Pressure Difference: | | The max. operating pressure difference between inlet and outlet of the solenoid valve. The solenoid can safely operate the valve below a pressure difference vale. | Nominal Pressure of a Solenoid Valve is the pressure PN in bar, max. static head that can be applied to solenoid valve to check the mechanical resistance of meterials, the fluid pressure must be below the highest nominal pressure value in order to avoid of damaging internal parts seals, diaphragm, cores etc.
| | Selection of Solenoid Valves: | There are some parameters for selecting the solenoid valves: Type of Media
Position of valve(normally closed, normally opened).
Pressure of media
Min. and max. pressure fall Temperature of media
Valve pipe size
Viscosity of media
Coil voltage and coil safety class
Suitable for your application. | | Application Safety: | Media must be protected from small particules.
Suitable voltage application to the electrical system.
Inlet side pressure fall is suitable.
Using a filter before the solenoid valve is recommended.
Connection of valve must be suitable for inlet-outlet of the pipe.
Valves can be mounted at any position. Horizontal position is recommended. Vertical position is not recommended.
Solenoid valves must have connection with ground . |
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