Temperature Control Element Bellow (TWB)

Temperature based volume expansion of the charge results in a displacement of the bellow. This can be used as a constant control or as switching function in connection with electronic or electro mechanical components. In many cases it is used as a direct mechanical actuator.


  • Function not requiring any auxiliary energy
  • Charge: fluid, wax, gas, adsorption charge, mixed phases, refrigerant
  • Expansion from 0.05 up to 0.6 mm/K
  • Applicable for temperatures from -35°C up to +380°C
  • Linear characteristic
  • Low hysteresis
  • Pressure or displacement limitation (only gas, refrigerant and mixed phases charges)

Copper, bronze (bellow only), brass or stainless steel, plating on demand.

Application field:
Building / industrial services, faucets, air conditioning devices, solar systems,
food and beverage industry, radiator thermostats (fixed head, remote sensors, remote and central controller), gas switches, discharge safety devices, industrial water mixers, hot water boilers.

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