Diaphragm seals are used to protect the pressure measuring instrument from aggressive, adhesive, crystallising, corrosive, environmentally hazardous or toxic media.
A diaphragm made of the appropriate material provides for the separation from the medium to be measured. Thus even the most difficult measuring requirements can be met by combining measuring instruments with diaphragm seals.
A fluid inside the system, which can be chosen to suit the particular application, hydraulically transmits the pressure to the measuring instrument.
Almost limitless application possibilities exist due to the large number of available variants, such as diaphragm seal designs or materials. The type of process connection (flange, threaded and sterile connection) and the basic method of manufacture are important design differentiation criteria.
For further technical information on diaphragm seals and diaphragm seal systems see IN 00.06 "Application, operating principle, designs".
Due to its design, the model 990.10 diaphragm seal with threaded connection can be used universally. A replacement of the lower body is possible (e.g. when changing the process connection) without having to carry out modifications on the diaphragm seal system.
Compared to the model 990.40 diaphragm seal, higher pressure ranges can be covered (smaller diameter of the diaphragm).
Assembly of the diaphragm seal and measuring instrument is made via a direct assembly as standard or optionally via a cooling element or a flexible capillary.
For the material selection WIKA offers a variety of solutions, in which the upper body, the diaphragm and the lower body can be made of identical or different materials. The diaphragm and the lower body can also be offered coated or covered with foils.
The model 990.10 WIKA diaphragm seal is particularly well suited for aggressive or hot media. This instrument is mainly geared to applications in the process industry.