A submersible oil pump unit with downhole driving conversion device

Abstract

A submersible oil well pump unit with a downhole drive conversion device, including a control cabinet with the function of automatic phase change by setting the load value according to the set frequency, a reciprocating oil well pump, and an asynchronous pump with a protector located in the downhole casing. Start the permanent magnet synchronous rotary submersible motor, and the reciprocating load-balanced downhole drive conversion device arranged between the submersible motor and the oil well pump. The invention does not need long rod transmission, and can adapt to well conditions such as multiple inflection points, high inclination, high head and the like which are not suitable for long rod drive. Compared with the linear submersible motor, the submersible motor of the present invention has higher output power and higher efficiency; it has better starting performance and higher power energy index than the traditional rotary submersible motor or permanent magnet motor; the compression springs arranged at both ends of the downhole drive conversion device can Improve operation reliability; the setting of oil storage capsules at both ends can ensure the reliability of the sealing performance of the inner cavity of the drive conversion device. The device can adapt to the needs of most oil wells for different lifts and displacements, and can operate reliably for a long time.

Description

technical field [0001] The invention relates to a submerged oil well pump unit, in particular to a submerged oil well pump unit with an underground driving conversion device. Background technique [0002] In the past, one of the main oil production facilities used in various oilfields at home and abroad was the ground-driven oil well pump unit. The rotary power generated by the rotary motor is converted into linear reciprocating power to adapt to the linear reciprocating operation mode of the downhole oil well pump. Its structural size is basically not limited by space, and its operating environment is suitable in the air. Therefore, its structure is firm, simple, and easy to maintain. It has always occupied the first place among many oil production facilities for more than a hundred years. Its defect is that it must rely on a very long sucker rod to transmit the linear reciprocating power output by the surface driving device to the downhole pump, so there is a large stroke...

AI Technical Summary

Problems solved by technology

Its defect is that it must rely on a very long sucker rod to transmit the linear reciprocating power output by the surface driving device to the downhole pump, so there is a large stroke loss, low mechanical efficiency, high energy consumption, and it is difficult to adapt to many inflection points, large slopes, Disadvantages such as high head well conditions, short maintenance period, large surface area on the well, and difficult management

[0003] For this reason, in recent years, some people have studied a linear submersible motor, which can output linear reciprocating power and directly drive the oil well pump downhole, thereby avoiding the defects caused by long sucker rods; however, this kind of motor is located in the oil well casing. , limited by the diameter, it is difficult to increase the power and output axial force, it can only adapt to the well conditions of low lift and small displacement, and the service life is short, so it is difficult to popularize

There are also a variety of creative ideas that use rotary submersible motors as power and drive oil well pumps through various drive conversion devices. So far, there have been no reports about such products.

The general defects of this kind of concept are as follows: traditional submersible motors (squirrel cage asynchronous motors) or permanent magnet motors have poor starting performance, and are not suitable for long-term frequent commutation startup; electrical system commutation needs to be controlled by signals from downhole sensors. Poor reliability; mechanical transmission device sealing system is not ideal, which affects the existence of defects such as operating life

Images