DEVICE FOR HYDRAULIC PROTECTION OF ELECTRICALLY DRIVEN BOREHOLE MOTOR FOR, MAINLY, ROTARY PUMP (VERSIONS) Russian patent published in 2014 - IPC F04D13/10 

FIELD: engines and pumps.

SUBSTANCE: proposed device is composed of protector arranged between motor and pump, housing, tube aligned with said housing and drive shaft, nipples, ring piston to reciprocate in ring chamber formed by said housing and said tube and to divide the chamber into two parts. Said parts are filled with dielectric and formation fluids. This device comprises separator of said fluids fitted in ring chamber on the side of ring piston end in contact with formation fluid and facing the second nipple for displacement independently of the piston. Said separator is composed of an integral part consisting of two tube lengths fitted one in the other and rigidly jointed by common bottom on ring piston side. Piston and separator are arranged in ring chamber to fit with clearance in housing inner surface and tube outer surface. Space of said clearance is sealed and filled with protective medium of hydro-oleophobic properties.

EFFECT: higher efficiency of protection, longer life.

30 cl, 12 dwg