WIKA Diaphragm Seal with Flange Connection (990.45)

High-temperature version to 450 °C [842 °F], with internal diaphragm


  • For processes with particularly high medium temperatures from 360 °C [680 °F] to a maximum of 450 °C [842 °F]
  • For gaseous and liquid aggressive media that are not highly viscous or crystallising, also in aggressive environments
  • Process industry
  • Oil and gas industry, chemical and petrochemical industries

Special features

  • Common standards and nominal widths available
  • When special materials are selected, all wetted parts are made of the selected material
  • Version with integrated flushing connections available

Sales Contact (Wika.sales@asyatrafo.com)




Diaphragm seals are used for the protection of pressure measuring instruments in applications with difficult media. In diaphragm seal systems, the diaphragm of the diaphragm seal effects the separation of the instrument and the medium.
The pressure is transmitted to the measuring instrument via the system fill fluid which is inside the diaphragm seal system.

For the implementation of demanding customer applications, there is a wide variety of designs, materials and system fill fluids available.

For further technical information on diaphragm seals and diaphragm seal systems, see IN 00.06 “Application, operating principle, designs”.

Model 990.45 is a high-temperature version consisting of the upper and lower body of a diaphragm seal. The lower body of the diaphragm seal can optionally be designed with flushing connections.

These components have been developed explicitly for applications with very hot media. The process connection is available in the established dimensions in line with the usual standards for this market.

Mounting of the diaphragm seal to a measuring instrument is usually made via a flexible capillary.