Bürkert Proportional Valves

Proportional valves are electrically operated by a solenoid or motor and are used to control the flow rates of liquids or gases.

Proportional solenoid valves are electromagnetic piston valves. There are two opposing forces in the valve: the force of the spring and the force of the proportional solenoid. Without power, the spring pushes the piston directly onto the valve seat, which keeps the valve outlet closed. But when power is supplied to the solenoid, the piston rises, the valve opens, and the fluid passes.

All proportional solenoid valves are normally closed, can be used with fluids at temperatures between -10°C and +90°C and comply with IP65 protection class.


Motorized proportional valves contain a powerful and high precision power supply. The force of the motor is transformed into the actuating element of the valve – so, the valve can be opened step by step.

Our range consists of small, compact and cost-optimized valves and impresses with precision, high dynamics and long service life.


All motorized valves are equipped with a precise electric motor as an actuator. The more structured valves (brass or stainless steel) comply with IP50 or IP54 protection class, can be used with temperatures between 0°C and +70°C and are suitable for work cycles up to 100%.

The valves are available in standard version (ON / OFF or control valve), in positioner version (analog or digital) and with integrated process controller (analog or digital).


There are three different versions of motorized valves:

  • Standard version for analog signals with limit switch detection
  • Positioner version for Fieldbus communication with position sensor system
  • Process controller version based on positioner with additional signal input for sensors

All versions have integrated control electronics. Commissioning is considerably easier as it is not additional.

A decisive advantage of motorized valves over solenoid valves is that the motor only requires electrical power.

Once the valve has reached the required opening, the motor shuts down and consequently no longer consumes energy.

Our technical sales office is available to study the suitable solution for specific applications.