Sealing drive shafts of mixing tools against housing of mixing container, for mixing powdered, grit-like and/or granulate-like materials, involves impinging sealing lip of shaft seal with cooled compressed air

摘要

Process for sealing the drive shafts (1) of mixing tools against the housing (7) of a mixing container for mixing powdered, grit-like and/or granulate-like materials involves impinging a sealing lip of the shaft seal (10) with cooled compressed air so that the air does not reach the container. An independent claim is also included for a shaft seal for carrying out the process. Preferred Features: The cooled compressed air is introduced from a connection via passages into feed lines (13) rotating with the housing. The compressed air is cooled to -30[deg] C before being introduced into the housing.