A chemical seal consists of a chamber filled with a transfer fluid (oil-based mixture), closed on one side by a pressure sensor and closed off from the process on the other by means of a diaphragm (stainless steel or plastic). The pressure bends the diaphragm and is transferred from the fluid to the pressure sensor.
Pressure transmitters are used if the process conditions no longer allow direct attachment of a pressure sensor (extreme temperatures, chemical resistance, hygiene requirements or media which form coatings or are very viscous ...). A wide range of process connections also allows use in special applications.
Principle of pressure transmitter