Centrifugal pump where rotor shaft also drives gear pump - esp. to achieve optimum conditions when drying oil in transformers

摘要

The pump body contains a driven shaft (6) carrying a rotor and one or more balded wheels forming the first pumping stage or stages. Downstream of the stage(s), shaft (6) carries a gear wheel meshing with pinions to form a gear pump. The pump is used esp. to control appts. employed for the sepn., degassing, or dehydration of liqs., partic. transformer oils or other dielectric liqs., where the pump motor is controlled via solenoid valves and is provided with a by-pass. The advantage is that the gear pump provides a constant flow while maintaining a constant suction (NPSH).