The 3 main types of solenoid valves are direct-acting, indirect-acting, and forced-lift valves. The major difference is the working style of these valves and their utilization at the various places of the circuit. The direct solenoid valve does require no differential pressure(inside and outside pressure) as compared to the indirect valves.
The indirect solenoid operated pinch valve does require a differential pressure to work and these are dimensional valves. The forced-lift pistons are placed in a position where higher pressure can be exerted. These valves can resist the higher pressure of the liquid where neither the above valves can’t work.
The short description of all the 3 types of the proportional solenoid valve is described below and their applications:
Direct-Acting Solenoid Valves:
The Direct-acting solenoid pinch valve does require no differential pressure to remain in its resting position. The Direct-acting solenoid valve is commonly used in the process line and also in simple isolation for safety purposes. The valves are only going to open/close by the movement of the armature by command or instruction.
There is no effect of the differential pressure on the direct valves and only the electrical pulses are used to open or close the valves. This is the main reason, you are calling these valves direct-acting valves. The direct-acting valves are directly open or closed by giving instructions as the differential pressure has no effect on their working.
In-Direct-Acting Solenoid Valves:
The indirect-acting proportional solenoid valve is affected by the differential pressure (inside and outside pressure). These valves open and close due to the differential pressure of the liquids and uses less energy as compared to the direct-acting valves. The indirect valves are one dimension and are used to keep the pressure within a certain limit.
These valves going to open after a certain pressure, to keep the pressure at a certain proportion. When you need to maintain a certain pressure limit of the liquid inside the reaction chamber, you are going to use the indirect-acting valves.
You can maintain the desired level of pressure inside and outside of the reaction chamber. The indirect-acting pinch pneumatic valve is going to open or close after a certain pressure or temperature.
Force-Lift Solenoid Valves:
The Force-lift solenoid valves are utilized where high pressure is expected. These valves are heavy-duty valves and are used at the main inlet or outlet pipes. The force-lifted valves are used to handle extreme pressure, and inside of them, a powerful coil is embedded. The valve orifice(opening) can handle extreme pressure due to its heavy-duty quality.
The Force-lift proportional valves are specially designed to endure high pressure. The coil of these valves is dually coiled for the electromagnetic force, and these valves are available according to your requirements of power.
Conclusion:
The three types of proportional solenoid valves are installed relative to their functionality. If you need direct functionality and control of the valves then the direct-acting valves are used. If you require one-dimensional valves, then the indirect-acting values should be installed. On the other hand, if you need heavy-duty inlet or outlet valves, the force-lifted solenoid valves should be utilized.
