Diaphragm seals

Diaphragm seals are used for pressure measurement when the medium must not come into contact with the pressure-bearing parts of the pressure measuring instrument. A diaphragm seal is a process connection with a separating diaphragm that separates the medium from the measuring instrument with a robust, elastic diaphragm. The interior space between the diaphragm and the pressure measuring instrument is filled with a pressure transmission fluid. If pressure is generated by the medium, it is transmitted via the elastic diaphragm to the liquid and further to the measuring instrument.

Optimal diaphragm seal designs, materials and filling media are available for every application. Diaphragm seals are manufactured with screw, flange, clamp connections and milk pipe screw connections with union nut or threaded connection. The dead-space-free diaphragm seals with flush diaphragms are particularly popular in the food and pharmaceutical sectors, as they ensure a hygienic and sterile process. Measuring units with diaphragm seals can be easily dismantled for cleaning or calibration.

If measuring instruments are connected to the process via a diaphragm seal, the most difficult measuring tasks can be realised. The diverse combinations enable pressure ranges of 600 mbar...1,000 bar even at extreme temperatures of -90 °C...+400 °C, aggressive, corrosive, abrasive, highly viscous, heterogeneous, toxic or aseptic media. Accurate pressure measurements are possible under demanding conditions, even at very low pressures of 600 mbar. To protect against corrosion in aggressive media, the diaphragm can be coated or made of special materials.