Magnetic Drive Pump for Slurry Applications (https://bungartz.de/pdfs/presse/WOPU0716Bungartz.pdf)

The benefit of magnetic driven pumps with regards to reducing Total Costs of Ownership has been widely accepted by endusers globally. Yet historically the usage of mag drives has been limited to application without any solids or small solid contents while using flushing systems to keep away solids from the magnetic drive. Such systems nonetheless limit the reliability of the pump by adding a system, that can′t be considered "inherent safe" due to instrumentation needed to safeguard operation of the pump. The same time it limits the ability of the pump to handle solids.

Unfortunately magnetic driven pumps are usually not able to run dry for prolonged period of time and often fail due to dry run related issues.

Processes that run at temperatures close to the Curie temperature of the magnets, where the magnet material irreversible looses its power, need cooling in order to assure the function of the magnetic drive. Conventional designs need fluid flushing by the pump fluid through the plain bearing to avoid overheating as the ceramic material utilized for the plain bearing displays a significant friction during dry running. As soon as the process fluid is close to Curie temperature the limitation is obvious.

The secret of a reliable magnetic pump operating under the above described condition though has been revealed long time ago by Bungartz from Germany.

Thanks to the unique design the pump fluid does not touch the bearing and in fact conventional ball bearings can be utilized instead of ceramic material plain bearings. The same time this pump is able to run continuously dry by design and can handle large amount of solids, both in vertical and horizontal design. Moreover as the pump fluid circulation is confined to the wet end of the pump - the casing and the impeller - any hot fluid can be handled without cooling up to 350C, while the temperature at the magnetic is still far away from the critical Curie temperature.

Happy exploring this proven technology !

PS While being at ease to talk about this technology I′m struggeling to format the temperature curve ;) If you want more details.... [email protected]