CENTRIFUGAL PUMP FOR PUMPING HIGH-VISCOUS HOT FLUIDS Russian patent published in 1994 - IPC

FIELD: pump engineering. SUBSTANCE: pump has case 1, shaft 2 with working wheel 3, face seal 5 with cooling buffer chamber 6 interposed between them, and heat exchanger 8 with hot and cold zones 9,10 received in a bore of case 1. Heat exchanger is made of inner and outer cylindrical bushings 10,11 provided with spacers 13. The bushing form space 14 which is sealed with respect to case 1 by flexible sealing rings 15. Face seal 5 has internal hydraulic loading. Cooling buffer chamber 6 is sealed from the pump space. Face 16 of heat exchanger 8 from the side of cold zone 9 has ports 17. Separating members 13 are made of longitudinal ribs 18 in hot and cold zones 9,10 alternatively. Multi-entering screw cutting 21, whose direction is opposite to direction of rotation of shaft 2, is provided on inner surface 20 of inner bushing 11 which faces shaft 2. EFFECT: simplified design, enhanced reliability and longevity. 3 dwg