Pump casing for sheet metal pump

A pump casing for a sheet metal pump, said sheet metal pump comprising:

• a motor, an impeller housed in the pump casing and driven by the motor, and a motor bracket fixedly engaging with the pump casing at one side thereof and the motor at another side thereof;
• improvements of said pump casing comprising:
• said pump casing including a pump body, a reinforced member and a seal ring that are being separately made and assembled together, the pump body being formed in a basin shape and having an inlet end plate remote from the motor bracket and an annular motor end plate;
• the reinforced member being housed in the pump body and having a water guide unit adjacent the inlet end plate and a flange unit adjacent the motor bracket, the water guide unit having a volute formed therein for housing the impeller;
• the seal ring being engaged with the water guide unit adjacent the inlet end plate and having an inner circumference adjacent the impeller around the inlet end plate;
• the flange unit having one side engaged with the pump body and another side thereof engaged with motor bracket, wherein the water guide unit and the flange unit are integrally made by a manufacturing method chosen from a group consisting of casting, CNC machining, and injection molding.