RU1808102C - Drive of sucker-rod screw pump - Google Patents

Abstract

SUMMARY OF THE INVENTION: A hollow drive shaft of a rod string is mounted vertically above the wellhead on bearings and is coupled to an output shaft of an electric motor. The output shaft is hollow and directly interfaced with the hollow shaft for joint rotation, which is equipped with an additional lower cantilever portion protruding beyond the bearings, provided at the end with means for sealing the gap between the inner surface of the shaft and the rod string. The body of reservoir fluid removal means is installed between the wellhead and the electric motor and covers the lower cantilever part of the drive shaft. The rod column has openings located between the gap sealing means for communicating the interior of the column with the gap cavity. The lower cantilever part of the drive shaft is provided with a portion of a perforated surface located in the area between the sealing units of the housing. Each wedge of the suspension string of the rods is made of two parts mounted with relative angular movement. 2 ill. Yo

Description

FIELD OF THE INVENTION This invention relates to equipment for oil production, designed to drive a sucker rod pump, and can be used in the operation of wells producing normal and especially high viscosity oil.

The purpose of the invention is to increase drive efficiency by simplifying the design and reducing the complexity of the process of adjusting the position of the rod string relative to the wellhead. FIG. 1 shows a kinematic diagram of a drive; in FIG. 2 is a top view of a wedge suspension.

The drive rod pump screw is arranged as follows.

At the wellhead 1, a drive motor is installed on the pedestal 2.

consisting of a stator 3 and a rotor 4 mounted on a hollow shaft 5. The hollow shaft 5 is mounted on two tapered bearings 6, 7, which receive radial and axial loads. The hollow shaft 5 of the electric motor is directly interfaced with the hollow hall 8 having cantilever sections protruding beyond the bearings 6. 7. In the boot shaft 8 there is a floor of the rods 9. is muffled in the upper part. It drives a screw pump and formation fluid rises through its internal cavity. (The column of the sucker rod pump is not shown in the drawing). In the hollow rod 9 there are holes 10 through which the plzst liquid from the internal cavity .ang enters the annular space between the hollow rod 9 and the hollow shaft 8, and then through the holes 11

into a conduit for draining formation fluid 12.

In the upper cantilever section of the shaft 8, there is a suspension wedge consisting of a housing 13, a main wedge 14, which moves in the axial (vertical) direction and accepts the axial load and the auxiliary wedge 15 installed in it. The latter has the possibility of angular movement relative to the main wedge 14 and transmits torque from the hollow shaft of the engine 5 and the hollow shaft 8 to the hollow rod 9.

The gap between the hollow rod 9 and the shaft 8 is sealed with seals 16 and 17.

In the lower cantilever portion of the hollow shaft 8, there are openings 11, on both sides of which wellhead seals 18 and 19 are located. They are installed in a single pedestal body 2. The cavity between the seals 18 and 19 is connected to the pipe for draining formation fluid 12.

The drive rod pump screw works as follows. When voltage is applied to the stator winding 3, the rotor 4 rotates together with the hollow shafts 5 and 8 and through the housing 13, the main wedge 14 and auxiliary wedges 15, the torque is transmitted to the hollow rod 9. From it through the column of hollow rods, the torque is transmitted to the screw pump (not shown in the drawing). The formation fluid pumped out by the pump rises along the rotating column of hollow rods. The axial load from the rod string and the liquid column is transmitted by the hollow rod 9, the main wedge 14 to the housing 13 and then the hollow shafts 8 and 5 and the bearing 7 through the pedestal 2 at the wellhead 1. The main wedge 14 is axially displaced in the housing 13. Auxiliary wedges 15 are disposed therein, which are mounted for angular movement relative to the main wedges 14. The auxiliary wedges 15 transmit torque. The formation fluid rising from the hollow rod 8 through the holes 10 enters the annular space between the hollow rod 8 and the hollow shaft 5. This space is sealed with seals 16 and 17, from which it is guided through the holes 11 into the cavity formed by the pedestal 2 and the seals mi 18 and 19, and further into the pipeline for draining the reservoir fluid 12.

The efficiency of the drive is due to the simplicity of the kinematic scheme, in which there are no any mechanical gears. At the same time, the complexity of the process of adjusting the position of the rod string relative to the wellhead is reduced. This operation is predetermined by the need to accurately install the pump screw relative to the cage (or the pump in

assembly relative to its seat nest). It is carried out after mounting the actuator on the mouth and consists in landing the column of hollow rods on the wedge 14. Moreover, with the main 14 and auxiliary 15

the wedges operate with one piece. The simplification of the operation of landing on the wedge also contributes to their location in the upper part of the drive. In the process of landing on the wedge, the column of hollow rods 8 can move up and down in a large range, due to the distance between the seals 16 and 17 - with the holes 10 being located between these seals.

The control of the drive operating mode — changing the number of revolutions — is carried out stepwise by switching the motor windings, or smoothly by using known systems for controlling the purity of rotation of the motor shaft.

Claims (1)

SUMMARY OF THE INVENTION comprising a wedge mounted vertically above the wellhead on bearing bearings and connected to the output shaft of the motor with a water shaft of the rod string, a wedge suspension including a wedge mounted with axial movement and contact with the outer surface of the column rods mounted concentrically inside the hollow drive shaft with the formation of a guaranteed, sealed in the upper part of the gap and with the possibility of joint the shaft of rotation of the outlet liquid pumped by the pump, including a housing with two opposed sealing assemblies between which a drain pipe is connected, so that and, in order to To simplify the design and reduce the complexity of the process of adjusting the position of the rod string relative to the axis of rotation of the hollow shaft, the output shaft of the electric motor is hollow and direct. it is interfaced with a hollow shaft for joint rotation, the latter is equipped with an additional lower cantilever portion protruding beyond the bearings, provided at the end with means of sealing the gap between the inner surface of the shaft and the rod string, the housing of the formation fluid removal means is installed between the wellhead and the motor and covers the lower cantilever part of the drive shaft, the rod string is provided with holes in its wall located between the gap sealing means for communicating the internal cavity of the column with the gap, and the lower cantilever part of the drive shaft is provided with a portion of a perforated surface located in the area between the sealing nodes of the body of the exhaust means, each wedge of the suspension of the rod string is made of two parts mounted with relative angular movement.