PROTECTION DEVICE FOR HYDRAULIC PROTECTION OF SUBMERSIBLE OIL-FILLED ELECTRIC MOTOR Russian patent published in 2004 - IPC

FIELD: oil producing industry.

SUBSTANCE: invention is designed for protection of submersible oil-filled electric motors used to drive submersible pumps from formation fluid. Proposed hydraulic protection device of electric motor contains housing, shaft with lower and upper end seals, flexible diaphragm secured on supports and enclosing shaft in zone under lower end seal, nipples between which pivot unit is arranged, upper and lower heads with flanges for connection, respectively, with pump and electric motor, valve, casing installed by means of flange on upper end seal, and baffle. Baffle is rigidly secured on shaft higher than upper end seal. Protection device is furnished with shaft extension and additional flexible diaphragm installed on shaped support and hermetically enclosing shaft extension in zone over upper end seal. Baffle is made in form of bushing installed on shaft extension over additional flexible diaphragm. Radial is installed from side of outer surface of bushing. Radial seal is made in form of cup arranged in upper head enclosing the bushing. Ring grooves are made in cup eccentrically relative to each other. Rings made of antifriction material and rubber rings with round cross section enclosing antifriction material rings are fitted on bushing and placed in ring grooves. Adjacent ring grooves are displaced in pairs relative to each other through 0.2-0.5 mm in diametrically opposite direction, and said pairs of ring grooves are turned relative to adjacent pairs in definite manner. Number of ring grooves is even, being not less than 6. Antifriction rings are pressed to each other along axis by spring-loaded ring, and additional flexible diaphragm is installed to form inner space communicating with ambient medium through air discharge valve, and from side of outer surface to form space communicating protection device with ambient medium.

EFFECT: provision of reliable protection of electric motor from formation fluid, increased service life o protection device.

2 dwg