SUBMERSIBLE PUMPING UNIT FOR SANDY FILTERLESS WATER WELLS Russian patent published in 2003 - IPC

FIELD: hydraulic machine building. SUBSTANCE: invention relates to water supply systems and is designed for pumping out water from filterless wells with unchecked sand production in concentration exceeding normal value for pump and complicating operation of water supply system. Proposed submersible pumping unit has induction motor, centrifugal pump, water intake port, heating pipe, cylindrical strainer, cylindrical sand collector, overstrainer funnel, ejector on delivery pipe, drain-and-wash duct, device to eject sand outside, automated drive of motor, detectors of limit water levels in well and pumping unit mode setter block, including water cleaning system regeneration setter. Housing of sand collector is gauze type, bottom of sand collector is conical, and suction hole of ejector is made in form of ring clearance. Ejector is furnished with filter-strainer on its pressure inlet. Regeneration setter comprises device to form steplessly changeable reciprocating movement of water in system. Invention is aimed at creating hydraulic conditions for pulp forming in sand collector of pumping unit before evacuation of sand from collector and improving cleaning of sand collector from settled grains, reducing head losses across ejector, improving cleaning of strainer, precluding penetration of sand into pump through ejector at reverse flow of water and shutdown of motor and reducing sand production. EFFECT: enhanced reliability in operation. 1 dwg