RU2309511C2 - Device for hydraulic protection of immersed electric motor of a supercharger - Google Patents

Abstract

FIELD: electro-mechanical engineering, possible use in immersed electric motors for actuating supercharger and, in particular, screw propeller.

SUBSTANCE: hydraulic protection device consists of penetrable and hermetic chambers, which are divided by immovable hermetic screen. In each chamber, concentrically positioned magnetic semi-screens. Additional pump is made reverse and positioned in the space between external surface of hydraulic protection device and internal surface of supercharger body, and filters are installed at input and output of cooling and oiling channels.

EFFECT: increased reliability of operation and increased durability of immersed electric motors.

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Description

The invention relates to the field of electrical engineering and can be used in submersible motors to drive a supercharger and, in particular, a propeller.

A device for protecting a submersible pump motor containing mechanical contact seals located along the shaft, and a reservoir for compensating leaks through seals [1].

This device does not provide high reliability of the electric motor, since mechanical contact seals always have leaks; the device also does not provide high durability of the electric motor, since the duration of its operation is determined by the dielectric reserve for leakage compensation.

A device for hydraulic protection of a submersible electric motor is also known, in which the sealing along the motor shaft is carried out by means of a fixed hermetic shell (screen) separating the leading magnetic coupling located in the sealed volume and mechanically connected to the motor shaft from the pump located in the volume with liquid and mechanically connected with the pump shaft driven magnetic coupling half. The heat is removed from the magnets and the screen, as well as the lubrication and cooling of the sliding bearings of the driven magnetic coupling half is carried out by forced running of the surrounding fluid using an additional low-power pump [2]. However, the use of a known device for sealing a submersible electric motor of a propeller drive is difficult due to the location of the supercharger outside the motor housing and the reversible (rotation in both directions) operation of the supercharger, while the well pump operates in one direction.

This invention is the closest in technical essence to the proposed invention.

The purpose of the invention is the expansion of the scope and increase the reliability and durability of the electric motor.

The drawing shows the proposed device as part of an electric motor for driving a supercharger (propeller).

A hydraulic protection device is installed between the electric motor 1 and the supercharger 2. The hydraulic protection of the fixed connections of the electric motor and the device is made in the usual way - using o-rings and gaskets.

The device consists of a permeable 3 and sealed 4 chambers, which are separated by a fixed sealed screen 5. The chamber 4 is a sealed volume formed by the housing 6 and the screen 5, and communicates with the internal sealed cavity of the electric motor 1. In each of the chambers there are concentrically located magnetic coupling halves separated by a non-magnetic screen 5. In the chamber 4, a leading coupling half 7 is fixed to the shaft of the electric motor 1, a shaft 8 passes through the chamber 3, on which the driven coupling half is fixed 9. The shaft is 8 is shielded in radial bearings 10 of the bearing shields 11, 12. The axial movements of the shaft 8 are limited by the thrust bearings 13. The bearing shield 11 has through holes 14 for communicating the permeable chamber 3 with the volume between the housing 15 of the blower 2 and the housing 6 of the hydroprotection device, in which the reversible pump is built 16, which pumps in the forward or reverse direction (depending on the direction of rotation of the supercharger) the surrounding fluid through filters 17, 18 along the screen 5, through axial 13 and radial 10 bearings, through axial 14 and radial 19 holes through the axial channel 20 of the shaft 8.

The device hydraulic protection of the submersible motor of the supercharger operates as follows.

When the electric propeller installation is immersed in the working fluid, the chamber 3 is filled with it, the sealing rings, gaskets, and the screen 5 impede the penetration of the working fluid into the chamber 4 and into the internal cavity of the electric motor 1.

During the operation of the installation, the leading 7 and driven 9 magnetic half-couplings rotate synchronously, transmitting torque from the electric motor 1 to the supercharger 2, rigidly connected by its body 15 to the shaft 8 of the driven half-coupling 9. In this case, an additional built-in pump 16 in volume between the housing 15 of the supercharger 2 and the housing Hydroprotection 6 pumps part of the working fluid through the filters 17, 18 into the hydraulic protection device in a parallel-serial circuit, removing heat from the screen 5 and cooling and lubricating the bearings 10, 13. The pump 16 is reversed When changing the direction of rotation of the supercharger 2, it changes the direction of flow of the coolant, thereby ensuring self-cleaning of the filters 17, 18, which increases the reliability and durability of the filters and the entire device.

Thanks to the proposed design of the hydraulic protection device, leakage of the pumped liquid into the cavity of the electric motor is completely eliminated, which makes it possible to design submersible electric motors on rolling bearings, with reduced thermal loads, using materials used in general industrial electric motors (for example, stator winding wires with thin insulation) , and consequently, with increased energy indicators and reduced values of vibration, while increasing n reliability and durability of submersible electric motors.

When the device is operating at depths of hundreds of meters, the electric motor can be filled with air; at large immersion depths, when difficulties arise in ensuring the mechanical strength of the screen as a vessel loaded with internal pressure, it is preferable to fill the sealed chamber of the device and the free volume of the electric motor with a liquid dielectric. By means of a liquid dielectric and a pressure compensator, for example a bellows type, external pressure is created on the screen, while its mechanical strength does not depend on the immersion depth.

Literature

1. A.S. 843107 USSR, MKI N02K 5/12. Device for protecting the electric motor of a submersible pump / V.V. Rodkin, V.V. Petrova / Opening. Inventions 1984. No. 27.

2. The device of hydraulic protection of the electric motor of a submersible pump. Patent for the invention of the Russian Federation No. 22010160 from 08/10/2003

Claims (1)

A device for hydraulic protection of a submersible electric motor, comprising a fixed sealed enclosure, leading and driven magnetic coupling halves, filters and a pump for cooling and lubricating hydraulic protection by forcing the ambient fluid through cooling channels and lubricating devices, characterized in that the pump for cooling and lubricating hydraulic protection is reversible and located in the volume between the outer surface of the casing of the hydraulic protection device and the inner surface of the compressor housing, len at the inlet and outlet of the cooling channels of the device.