This innovative design for a submerged electric motor pump is implemented for transferring aggressive refrigerated liquids (like ammonia). Several unique design features are incorporated since most of these liquids are known for their challenging chemical characteristics such as corrosiveness to copper.
The motor is encased in a sealed housing that has nitrogen gas flowing into it from the top of the tank or suction vessel to keep the motor dry and inert, thereby providing a safe environment. The enclosed motor is cooled by the pumped liquid surrounding the motor housing and by fan blades fitted to the motor rotor. The motor rotor is supported by two deep groove bearings lubricated with low temperature grease.
The hydraulic (wet) end with the impeller(s) and inducer is driven by a magnetic coupling located between the motor and wet end upper shaft. The motor side half of the magnetic coupling is housed inside the sealed motor housing adjacent to the stainless steel membrane. This allows the wet end to be driven while keeping the fluid out of the motor.
The ACC/ACR type can be installed inside a suction vessel much like an ECC pump, or into a storage tank in the same fashion as an ECR pump. It can also be installed inside the cargo tanks for chemical tankers.