How to use pressure sensors for harsh environments

How to use Pressure sensors for harsh environments

Physical separation from hazardous media

A fluid-isolation barrier (see diagram below) can be implemented to prevent corrosive media coming into direct contact with the sensor diaphragm.

The fluid-isolation system (as shown above) is closed to allow accurate measurement, taking advantage of the incompressibility of the liquid. A suitable liquid must be chosen that will not mix with the pressure media, or present risk of contamination to the process being monitored. Heavy industrial oil is often used.

Temperature isolation can be implemented in a similar way, by inserting a standoff such as an uninsulated tube between the main vessel containing the media and the sensor –industrial pipework or a flask might be used, for example.

Heat is dissipated from the media in the tube (see diagram above), thus exposing the sensor diaphragm to a safe temperature. The length of tubing needed is calculated according to the temperature of the media, thermal properties of the tubing, and the maximum temperature of the pressure sensor.