Servo controlled solenoid valves
These solenoid valves are a combination of the pilot operated valves and the direct acting valves. The armature is mechanically connected to the diaphragm on which there is a pilot office. With minimal pressures the solenoid valve acts like a direct acting valve. Total opening as well as full flow do not occur at low pressures. With higher pressures it works as a pilot operated valve with full opening. Average response time 50 ÷ 500 ms.
Servo-controlled solenoid valves are mainly used for large orifice diameters starting from ½ inch. An overview of these valves can be found in our section solenoid valves for water.
- Servo controlled 3/4 "solenoid valves for steam
- Stainless steel solenoid valves servo-controlled
- Servo-controlled latching solenoid valves 1/4 "to 1/2"
Pilot operated solenoid valves
This solenoid valve uses the force of the fluid to operate the valve via a suitable integral pilot valve. The inlet pressure must always be at least the same as the minimum ΔP figure shown on the datasheets. Using the same coils as direct acting valves much higher fluid volumes and pressures can be controlled with this solenoid valve. Average response time 50 ÷ 500 ms.
Pilot operated solenoid valves offer the advantage of switching without differential pressure. These valves are available starting at 0 bar input pressure, with orifice diameters up to 1 inch. The standard brass valves are listed in the following categories:
Direct operated solenoid valves
When energized the coil electrically generates a magnetic force attracting the armature towards the fixed core. Inside the armature is a seal that acts upon the main orifice, either when the coil is de-energised (normally closed) or when the coil is energised (normally open). By revealing the orifice allows the fluid to pass. Average response time 5 ÷ 25 ms.
Direct operated solenoid valves are preferably used in automation and with 1/8 "and 1/4" connections. In addition to standard valves, we also offer solenoid valves made of stainless steel, for hot water and steam, high-pressure valves up to 200bar, latching solenoid valves and versions for ATEX.
Solenoid valves with closing damping
Pilot operated solenoid valves (only versions specified in each datasheet) can be supplied with a system that regulates the closing speed of the diaphragm in order to control waterhammer.
The seal closing speed is operated by the adjusting screw: by screwing it clockwise (in the "+" direction) when using liquid, the valve will close slower reducing any waterhammer effect that may occur in the solenoid valve and the upstream pipes. In the case of larger valves (1 1/4", 1 1/2" and 2"), please adjust the anti-waterhammer screw to ensure that that valve closes as slowly as possible in order to avoid causing any damage that may affect the functioning of the equipment and valve due to the waterhammer effect.