DRY-TYPE SEALED SUBMERSIBLE MOTOR FOR WELL PUMP Russian patent published in 1997 - IPC

FIELD: submersible motor-pump units for evacuating liquids from wells. SUBSTANCE: chamber 12 of magnetic-liquid sealing arrangement formed by pole pieces 8 and 9, magnet 7, and shaft extension 11 communicates with annular chamber 14 in upper end shield 5 through channel 13 in lower pole piece 9; chamber 14 communicates with atmosphere through hole 15. Chambers 12 and 14 their communicating channel 13 are filled with inert liquid 22. Corrugated flexible pressurizer 19 and its stops 16, 18 are made in the form of semi-spheres. That of pressurizer 19 is located in lower stop 18. Inner space of upper stop 16 communicates with motor interior through channel 17 and lower stop 19, with atmosphere through hole 20. EFFECT: improved design. 3 cl, 3 dwg