Piston instead of diaphragm: KD 21 piston type chemical seal

The new AFRISO KD21 piston type chemical seal, an extremely robust unit, can be used to measure the pressure of abrasive media in conjunction with a Bourdon tube pressure gauge, a pressure transducer or a pressure switch. The KD21 piston type chemical seal operates under the most adverse conditions, for example drilling platforms, mining, tunnel construction, systems for removal of excavated material, concrete pumps, mortar spraying machines or for processing ceramic materials. KD 21 features a 6 mm thick stainless steel piston; conventional diaphragms of chemical seals wear too fast as a result of permanent contact with abrasive solids in such applications. The measuring system (chemical seal, mounting, measuring instrument) is highly reliable since the chemical seal and the measuring instrument are welded together to form an inseparable, shock- and vibration-resistant unit. The KD 21 chemical seal is filled with biologically non-hazardous paraffin oil (FM 9); it is designed for media temperatures of -10 °C to 80 °C and available for pressure ranges from 0/10 bar to 0/600 bar. The accuracy of the measuring result is not affected by a reduced thickness of the membrane occurring as a result of the process. Due to its compact design, the KD 21 chemical seal can be combined with a great variety of mechanical and electronic pressure measuring instruments. AFRISO supplies chemical seal options with different pressure transmission liquids and materials, with capillaries or cooling elements. In addition, pressure gauges are often equipped with rubber protectors for use in rough environments. This allows reliable operation of these measuring instruments even under extremely harsh conditions.