Each rotating pump has a drive shaft that has to be sealed in some way. Sealing can be performed through a magnetic coupling, a stuffing box packing, a viscoseal with reverse conveyance threads, a single or double mechanical seal, a multiple lip seal or through combinations of the previously named systems.
Depending on the chemical pump type and place of use, different systems may be used. The limitation of the selected width of the seal types is defined by the process parameters. Pressure, temperature and viscosity are decisive factors that influence or limit the selection of the seal.