LABYRINTH-SCREW PUMP FOR HANDLING MOLTEN METAL Russian patent published in 2007 - IPC F04D3/02 

FIELD: liquid metal-cooling reactor plants.

SUBSTANCE: proposed labyrinth-screw pump for transfer of molten metal has housing accommodating gas-sealed shaft with drive installed in bearing unit, threaded bushing installed in housing below level of pumped medium, and screw secured on shaft coaxially with threaded bushing. Conical gauze forming radial clearance between upper base of cone and shaft of pump is installed over bushing with resting on bushing through base. Gas or gas mixture is delivered into ring chamber made in bushing and communicating with clearance between bushing and screw.

EFFECT: increased service life and improved reliability of pump owing to reduction of ingress of dispersed particles into clearance between working surfaces, passivating of these surfaces and recovering of admixtures of coolant oxides.

1 dwg