Canned motor and pump employing such canned motor

A pump comprising:

• a canned motor unit comprising a stator, an outer frame casing disposed around said stator and having a pair of axial open ends, a pair of side frame members welded to said open ends, respectively, of the outer frame casing, a can fitted in said stator and joined to said side frame members, a shaft rotatably disposed in said stator, a rotor mounted on said shaft and disposed in said can, and an outer cylinder of sheet metal disposed around said outer frame casing with an annular space defined therebetween, said outer cylinder being welded to said outer frame casing, said outer cylinder having a pair of flanges disposed respectively on axially spaced open ends thereof for attachment to components of a pump assembly and holding a fluid being handled within said outer cylinder, said outer cylinder having a hole defined in an outer circumferential wall thereof for passing leads for connection to a power supply;
• a plurality of pump units each having at least one impeller and a pump casing housing said impeller;
• and
• a casing unit having a casing with a discharge port defined therein, said canned motor unit being connectable to said pump units and to said casing unit to form a pump;
• wherein the pump casing of each of said pump units may be connected to one of said flanges of the outer cylinder with said impeller fixedly mounted on an end of said shaft, and wherein one of the group consisting of said pump units and said casing unit may be connected to an other of said flanges of the outer cylinder to form said pump.