Heavy oil anti-blocking device for electric submersible pump protector

Abstract

The invention discloses a heavy oil anti-blocking device for an electric submersible pump protector. The heavy oil anti-blocking device comprises an upper joint, a capsule shell, a capsule, and a shaft, the upper joint is fixedly connected with the capsule shell, the upper end of the shaft penetrates through an axial through hole of the upper joint from the capsule shell and is then connected withan oil-gas separator shaft through a spline sleeve, and a mechanical seal assembly is installed between the shaft and the upper joint; an axial breathing hole of the upper joint communicates with aninner cavity of the capsule shell and an inner cavity of the upper joint; a stirring wheel and a sieve plate assembly are fixedly installed on the shaft located in the inner cavity of the upper jointfrom top to bottom; the upper joint is provided with two radial through holes which are formed in the position above the stirring wheel, and a liquid-outlet check valve and a liquid-inlet check valveare fixedly installed in the radial through holes correspondingly; and a heating device sleeves the outer side of the upper joint. The situation that the breathing hole of the protector is blocked byheavy oil can be reduced or eliminated, the service life of the protector is prolonged, the heavy oil anti-blocking device is better suitable for oil well exploitation of heavy oil, super heavy oil and extra heavy oil, and thus the service life of an electric submersible pump unit is prolonged.

Description

technical field [0001] The invention relates to a protector for an electric submersible pump of oil pumping equipment for oil and gas development, in particular to a heavy oil anti-blocking device for the protector for an electric submersible pump. Background technique [0002] The submersible electric pump downhole unit is mainly composed of a multi-stage centrifugal pump, an oil-gas separator, a protector, and a submersible motor connected from top to bottom. The shells are connected with flange screws, and the shafts Connect with spline sleeve. [0003] The function of the protector is to compensate the loss of lubricating oil in the motor, balance the internal and external pressure of the motor, prevent the well fluid from entering the motor and bear the axial load of the pump. The main types of protectors are connected type, precipitation type and capsule type. The advantages of the capsule protector: the capsule is used to isolate the well fluid and the motor lubrica...

AI Technical Summary

Problems solved by technology

[0004] Heavy oil (crude oil with an underground viscosity greater than 50Pa·s) has the characteristics of high asphaltene and colloid content, high viscosity and poor fluidity. During the lifting and mining process using submersible electric pump units, the breathing holes are often blocked by heavy oil blocks , making the protector not breathe well, or even unable to breathe, causing the protector to lose its basic function of free replacement of the internal motor oil with the external well fluid according to the temperature change of the submersible electric pump unit, and maintaining the internal and external pressure balance of the submersible motor

Due to the failure of the protector in a short period of time, the well fluid enters the submersible motor, and eventually the submersible motor has no insulation and burns out, which causes the submersible electric pump unit to stop and lie down in the well, causing huge economic losses and resulting in heavy oil production. high cost

Images