Diaphragm seal systems should be used if the process media and the device should be separated.
Diaphragm seal systems offer clear advantages in the following instances:
• In the case of high process temperatures
• In the case of process media that crystallise
• In the case of corrosive or highly various process media or process media with solids content
• In the case of heterogeneous and fibrous process media
• If good and rapid measuring point cleaning is necessary
• The measuring point is exposed to vibration (e.g. better view of display).
Design and Operation Mode
Diaphragm seals are separating equipment between the measuring system and the process medium.
A diaphragm seal system consists of:
• A diaphragm seal in a one-sided system, e.g. FMD 630 or two diaphragm seals, in a two-sided system, e.g. FMD 633
• Capillary tube
• Fill fluid and
• A differential pressure transmitter.
The process pressure acts via the diaphragm seal membrane on the liquid-filled system, which transfers the process pressure via the capillary tube onto the sensor of the differential pressure transmitter.
Endress+Hauser delivers all diaphragm seal systems as welded versions. The system is hermetically sealed, which ensures the highest reliability.