Solenoid Valves are used to lock and to dosage fluid and gasous medias as well as steams. They are multiple used for example in hydraulic, pneumatic, drink water supplies, petrochemical, heating circuits, fueling units, water preparation and many other applications in general machine and fitting industry. Hydraulic valves are especially used for strat, stop and direction changes of fluid in hydraulic systems.
Basically you can find four different types of control for electro-magnetic valves.
- Directly acting electro-magnetic valves:The anchor of the electro magnet moves directly the seat and generates a stroke. This valves do not need any differential pressure to switch.
- Indirectly acting solenoid valves respectively servo controlled valves: A directly acting solenoid valve is integrated as a pilot valve (so called servo valve). The valve stroke is realized by the medium pressure. A low differential pressure is needed. The minimal needed pressure is listed as minimal pressure. High pressures can be controlled with this type of control with small magnets.
- Positively controlled electro-magnetic valves: A directly acting electro-magnetic valve is integrated as pilot valve. Additionally the anchor is mechanically coupled to the diaphragm. The stroke of valve is realized by the medium pressure and the anchoring force. Valves of this type switch from 0 bar on. Also in this case higher pressure and higher nominal width can be realized with small magnets.
- Pneumatic acting valves: The Stroke of valve is realized by a pneumatic drive. The activation is started by an extrenal pilot valve. With this type valves high temperatures, high pressures, polluted medias and aggressive operating fluids etc. can be controlled.
Furthermore solenoid valves can be differed in their type duties they can have 2, 3, 4, 5 and more ways (connections).
- 2/2-Way solenoid valves have 2 controlled connection and 2 change overs (open and closed).
- 3/2-Way solenoid valves have 3 controlled connectiosn and 2 change overs. They are used to activate single acting cylinders as signal transmitters and for the position monitoring of cylinders in penumatic controlled appliances.
- 4/2-Way solenoid valves have 4 controlled connections and 2 change overs to control double acting cylinders.
- 4/3-Way solenoid valves also have 4 connections and 2 change overs. They are additionally equipped with medium position.
- 5/2-Way solenoid valves are predominantly used to pilot double acting cylinders. These types of valves have 2 operating connections, an air supply connection and 2 exhaust air outlets.
- 5/3-Way solenoid valves are similar in their function to the 5/2-Way valves they are only additionally equiped with a medium position which can be defined by the user.