Contact
Construction type
Diaphragm valve
Piston valve
Nipple valve
Ball valve
Coaxial valve
Pinch valve
Control type
Pilot operated
Directly acting
Forced pilot operated
Externally controlled
Connection type
Thread connection
Flange connection PN16
Welding connection
Flange connection PN40

Diaphragm valves

Diaphragm valves with solenoid actuator are used to shut off gaseous and liquid media in pressurized pipelines.

The sealing element is a circular, bulging, rubber diaphragm with a special shape. The diaphragm is clamped between the valve cover and the fitting, whose flexibility enables the stroke movement.

We distinguish between 2 control types for diaphragm valves:

  • servo-controlled diaphragm valves: (see function video type 40) The stroke movement OPEN/CLOSE is solely effected by the existing pressure difference.
  • Force-controlled diaphragm valves: (see function video type 43) The stroke movement is,
  1. directly by the magnetic force if no pressure difference is present between the inlet and outlet,
  2. supported by any pressure difference present.

Features of diaphragm valves:

The entire interior, from the valve base to the solenoid armature, is surrounded by the operating medium. This means that when determining the valve, attention must be paid to the suitable materials, both the diaphragm quality and the metallic materials. The flow direction for diaphragm 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. This characteristic is also referred to as reverse flow open. Diaphragm valves are available in seat sizes from 13 mm to 50 mm in the form of threaded and flanged valves. Diaphragm valves are simple in design, maintenance-free and suitable for high switching cycles.

The choice of material combinations, both in terms of diaphragm quality and body material, means that a wide range of different operating media can be controlled. At temperatures between -30°C and +140°C, the operating medium can assume the aggregate state gaseous, liquid or vaporous.

Diaphragm valves are ** normally closed (NC valve)** as standard. Further options:

  • normally open (NO valve)
  • ATEX
  • Limit switch for detecting the OPEN or CLOSED end position
  • oil and grease-free
  • Emergency manual operation
  • Flood-proof IP68

A combination of these is also possible. All options can be easily and efficiently determined using the Valvescout selection tool.

Technical data and versions:

  • Electromagnetic actuators: 7 to 100 watts
  • Protection classes: IP65 - IP68
  • Duty cycle: 100%
  • Connection types: G-thread DIN ISO 228, NPT or flange connection PN16/40, ANSI, tongue/groove
  • Nominal sizes: DN13(15) to DN50
  • Operating pressure: max. 20 bar
  • Body materials: brass, stainless steel, gray cast iron, cast steel, ductile iron
  • Diaphragm materials: NBR, EPDM, FKM