Miniaturized pressure compensation seals for the latest Baumer pressure sensor generation

High-performance diaphragm solution for pressure measurement technology

The autoclavable PBMG pressure transmitters by the Baumer Group are a perfect field of application for the mini pressure compensation seals (PCS) by Schreiner ProTech. The pressure transducers meet the hygienic requirements of the food and pharmaceutical industries, are particularly rugged and resist high process temperatures of up to 140 degrees centigrade. Due to the compact dimensions of the cylindrical housing with a diameter of 22 mm they can be installed even in small pipes and vessels. The mini PCS with a diameter of 3 mm and a vent hole of 1.2 mm can be accommodated even in these constrained installation conditions.

Electronic pressure transducers have to meet very high demands particularly in the food and pharmaceutical industries. The fully autoclavable Baumer PBHM pressure transmitter resists the commonly used sterilization processes and delivers convincing temperature performance. With the protection cap installed the devices withstand an ambient pressure of 3500 mbar.

“An opening in the sensor assures that the pressure inside the sensor is the same as the ambient pressure,” explains Stefan Brönnimann, head of development at Baumer. To prevent the intrusion of water, this opening is closed with a pressure compensation seal. Due to the very compact design of the latest product generation the size of the PCS had to be adjusted as well. The mini PCS with a diameter of 3 mm and a diaphragm opening with a 1.2 mm diameter were successfully tested and are now in use. “Despite the very small size of this functional component all the technical requirements to assure permanent protection of the sensor electronics are met,” says Michael Spörl, the responsible product manager at Schreiner ProTech. The diaphragm of the PCS provides the required pressure compensation due to its air permeability while protecting the electronics from the intrusion of water. The venting solution is adhesion-bonded to stainless steel type 1.4404 and meets IP67 requirements, thus easily resisting long-term service temperatures from -10 to 85 degrees centigrade.