The sealing element is a metal piston or flat plate with an annular seat seal. The piston is guided in the valve cover by special piston guide bands and grooved rings. This type of valve is robust, suitable for high pressures and, through the use of a wide variety of sealing materials, suitable for a wide range of applications. Due to the shape of the piston, the valves are usually higher than diaphragm valves. Piston valves are more sensitive to contamination than diaphragm valves due to the relatively large piston surface area.
We distinguish between 2 types of piston valves:
- Servo-controlled piston valves: The OPEN/CLOSED stroke movement is effected by the existing pressure difference.
- Force-controlled piston valves: The stroke movement is:
- directly by the solenoid force if no pressure difference is present between inlet and outlet,
- assisted by any pressure difference that may be present.
Features Piston valves:
The complete valve is surrounded by the medium inside.
This means that when determining the valve, attention must be paid to suitable materials. The direction of flow for piston valves is fixed. The valve closes, supported by the spring force, under pressure in the direction of the arrow. Pressure against the direction of the arrow and the valve opens. We refer to this characteristic as reverse flow open. Piston valves are available in nominal seat width from 13 mm to 150 mm in the form of threaded and flanged valves.
Due to the choice of material combinations, a variety of different operating media can be safely shut off. The operating medium can assume the aggregate state gaseous, liquid or vapour at temperatures between -200°C and +300°C.
Piston valves are normally closed (NC valve) as standard. Further options and possible combinations:
- normally open (NO valve)
- Limit switch for detection of end position OPEN and/or CLOSED
- oil and grease-free
- Emergency manual override
- Low temperature version
- Hot steam version
- Underwater installation IP68
All options can be easily and efficiently determined using the ValveScout https://www.buschjostventile.de/en/ventil_scout tool from Buschjost Magnetventile GmbH & Co. KG can be determined easily and efficiently.
- Body choice 1.4305, 1.4571, brass
- Variety of seals PTFE, FKM, EPDM, PTFE, Peek
- large selection of options
- Wide temperature range -200°C to +300°C
- application range vacuum to high pressure
- as solenoid valve and electro-pneumatic valve
Technical data and versions:
- Body materials: brass, stainless steel, grey cast iron, cast steel
- Seal materials: PTFE, PEEK, special materials
- Electric solenoid actuators: 7 to 100 watts
- Protection classes: IP65 - IP68
- Duty cycle: 100%
- Connection types: G-thread DIN EN 228, NPT or flange connection PN16/40, ANSI, groove/spring
- Nominal sizes: DN13(15) to DN150
- Operating pressures: 16 bar, 25 bar, 40 bar, 70 bar ... 450 bar
Series, solenoid valve/piston/servo-controlled
Series, solenoid valve/piston/forced pilot operated
Series, solenoid valve/piston/externally controlled