There are two distinctive designs of glandless pumps, one with dry stator windings (Canned Rotor Motor) and one with wet-stator windings (Wet Stator Motor).
With this design, there is no shaft seal between the pump and the motor. The pumped medium is used for cooling and lubricating the motor at the same time. Glandless pumps are considered to be particularly low-noise, which makes them ideal for use in living spaces. The omission of the shaft seal makes the system particularly low-maintenance and leakage-free. This also makes canned motor pumps interesting in process technology for applications where leakage-free pumping is important.
A disadvantage is the lower efficiency compared to pumps with shaft seals (glanded pumps), especially at higher outputs.
Typical applications for canned rotor pumps are as heating circulating pumps, process pumps for the chemical industry and process engineering and as nuclear reactor pumps. Wet stator pumps are mainly used as submersible pumps in wells and for circulating duties in conventional power plants.