RU2283969C1 - Sucker-rod pump drive - Google Patents

Abstract

FIELD: oil extraction industry; lifting oil from boreholes.

SUBSTANCE: proposed sucker-rod pump drive has motor and reduction unit both mounted on baseframe common with housing. The latter accommodates mechanism that functions for rotary-to-reciprocating motion conversion and has driving and top sprockets with closed chain around them which is coupled with carriage connected to counterpoise. The latter is U-section structure mounted in housing guides with chain disposed in its open cavity; counterpoise is coupled through flexible link with rod suspension assembly. Vertical symmetry axes of conversion mechanism, counterpoise, and flexible link are disposed in immediate proximity of one vertical plane. Top sprocket is mounted within housing for rotation and restricted movement along conversion mechanism axis for adjusting chain tension. Lubricating oil bowl is provided in bottom part of housing. Reduction unit is provided in addition with manual off-operation drive for setting driving sprocket in rotary motion. Top sprocket is designed for restricted axial displacement and locking. Counterpoise is provided in addition with removable locks designed for counterpoise suspension relative to housing in any desired position and with two dippers installed at bottom of counterpoise sideways of closed chain; they have bottom holes in side wall facing the closed chain. Dippers are mounted for immersion in lubricating oil bowl in bottom position of counterpoise; dipper size ensures lubricating oil outflow to chain during counterpoise reciprocation. Manual off-operation drive is mounted on withdrawable support frame and is made in the form of self-braking worm pair whose worm gear is mounted on reduction unit shaft; worm is installed in revolution supports of withdrawable support and is coupled with revolution drive handle. Frame mounts revolution support with shaft that couples reduction unit drive shaft and driven sprocket for torque transfer.

EFFECT: enhanced reliability and service life, facilitated maintenance.

3 cl, 9 dwg

Description

The invention relates to the oil industry, in particular to technical means for lifting liquids from wells, and can be used to extract oil from wells using rod pumps.

The well-known "Drive sucker rod pump" (see US Pat. RU No. 2150607, F 04 B 47/02, publ. 06/10/2000; Bull. No. 16), containing mounted on the basis of a single frame engine, gearbox, rotary converting mechanism reciprocating movement, including the driving and driven sprockets, covered by a closed chain connected to a carriage connected to a counterweight made in a U-shape in cross section and installed in the guides of the housing with the chain in its open cavity and connected through a flexible link with suspension unit Tang, wherein the axis of the converting mechanism, the counterweight and the flexible link are in the same vertical plane, the upper sprocket mounted in the housing rotatably and axially limited movement converting mechanism for adjusting the chain tension.

Also known is the "Drive of a sucker-rod pump" (see US Pat. RU No. 2200876, F 04 B 47/02, publ. March 20, 2003; Bull. No. 8), containing a motor mounted on the base and placed on it, a mechanism that converts rotational movement into a reciprocating movement, including a driving pulley and a curved guide element with a constant radius of curvature, covered by a continuous flexible link connected to the carriage connected to the counterweight, which is installed in the guides and connected through a flexible link with the rod string, while the counterweight is made prefabricated, and the main counterweight normalizes the operation of the pump drive, equipped with rods of minimal cross section and lowered to the minimum depth of the well, and additional counterweights are made with the possibility of placing their mass symmetrically relative to the axis of symmetry of the plane of the continuous flexible link on the main counterweight, while the total center of gravity is located in the immediate proximity to this plane, and the flexible link connecting the counterweight to the rod string is placed with the formation of an even number of parallel tvey, and the connection nodes of the branches of the flexible link with the counterweight are placed pairwise symmetrically with respect to the axis of symmetry of the flexible link outside its contour, while the connection nodes of the flexible link with the counterweight and the suspension node of the rods are made to ensure the same tension of all branches of the flexible link, the frame with wheels and additional drive installed on the base, with guides and stops, with the possibility of forced limited limited stops stops moving in a horizontal plane and in a conical angle relative tionary vertical axis, also frame is fixable relative to the base in any position, wherein the wheels are capable of cooperating with the guides.

A common disadvantage of these analogues is the low reliability and durability due to the lack of a closed circuit lubrication system.

Closest to the technical nature of the proposed drive is a "Drive sucker rod pump" (see Patent US No. 4916959, Int. Cl. 4 V 66 V 5/26), containing installed on the basis of a single frame with the body of the motor, gearbox, placed in the case, a mechanism that converts rotational motion into reciprocating, including the driving and driven sprockets, enclosed by a closed chain connected to a carriage connected to a counterweight made in a U-shape in cross section and installed in the guides of the housing with a size chain in its open cavity and connected through a flexible link with the node of the suspension rods, and the axis of the converting mechanism, the counterweight and the flexible link are close to one vertical plane, the upper sprocket is mounted in the housing with the possibility of rotation and limited movement along the axis of the converting mechanism to regulate the chain tension , and in the lower part of the housing is a container for lubricating oil. In this drive, the oil level in the bath must reach the lower sprocket to ensure chain lubrication.

The disadvantage of the closest analogue is the large required volume of the bath and lubricating oil, since in the lower position of the counterweight the carriage is immersed in the oil bath at least half the height. Under certain operating conditions of the drive, characterized by a large load on the chain at a low speed and a long stroke, lubrication of the chain by dipping a small section of the chain into the oil bath may not be enough, which reduces the durability of the drive.

Common disadvantages of all the analogues are:

- low reliability and durability due to the lack of a closed-circuit lubrication system;

- the inability to adjust the position of the driven sprocket in relation to the leading makes it difficult to install them in one plane, which also reduces the durability of the transforming drive mechanism;

- the complexity and complexity of the connection (and disconnection) of the suspension unit of the actuator rods with the wellhead rod transmitting movement from the actuator to the rod string, since after the descent of the sucker rod pump into the well, the wellhead rod is in the lower position and it is also necessary to lower the suspension unit to connect it , for which it is necessary to raise the counterweight to the upper position, which is not possible using your own drive motor (the weight of the counterweight is chosen equal to the weight of the rod string plus half the weight of the raised column liquid, and the power of the drive engine - based on the lifting of half the weight of the liquid column, because during operation of the drive, when the counterweight and the rod string are connected by a flexible link, only this part of the load remains unbalanced);

- low maintainability due to the lack of the possibility of fixing the counterweight in the case, if necessary, temporarily disconnecting the chain, the flexible link, the carriage parts and other nodes for their revision and replacement. The installation of the drive sprocket in the known drive directly on the output shaft of the gearbox also reduces the maintainability of the drive, since it is impossible to dismantle the gearbox without disconnecting the drive sprocket from the closed circuit of the conversion mechanism, in addition, this design requires the use of a special gearbox with an increased length of the output shaft, designed to increase load, because in addition to the torque, it has a cantilever load equal to the traction of the closed circuit .

The technical task of the invention is to increase the reliability and durability of the drive due to the guaranteed lubrication of the entire chain and the sprockets interacting with it at any speed and length of its movement, as well as to simplify its maintenance due to the possibility of fixing the counterweight in the case if necessary, temporary disconnection from chain, simplifying the connection (and disconnection) of the suspension unit of the actuator rods with the wellhead rod, the ability to adjust the position of the driven sprocket in relation to the leading makes it difficult and unit in a single plane.

The specified technical problem is solved by the proposed borehole sucker-rod pump drive, comprising an engine, a gearbox mounted on the base on a single frame with the casing, a mechanism placed in the casing, converting rotational motion into reciprocating and including a drive and upper sprockets covered by a closed chain connected to the carriage, connected to a counterweight, which is made in a U-shape in cross section and installed in the guides of the housing with the placement of the chain in its open cavity and connected through a flexible link with a rod suspension unit, the vertical axis of symmetry of the conversion mechanism, the counterweight and the flexible link are located in the immediate vicinity of one vertical plane, the upper sprocket is mounted in the housing with the possibility of rotation and limited movement along the axis of the conversion mechanism to regulate the chain tension, and in the lower part of the housing is a container for lubricating oil.

What is new is that the gearbox is additionally equipped with a switchable manual drive for rotating the drive sprocket, and the upper sprocket is made with the possibility of limited axial movement and fixing, while the counterweight is additionally equipped with removable latches made to suspend the counterweight relative to the housing at any desired location, and two buckets mounted below the counterweight on the sides of the closed chain and made with holes from the bottom in the side wall directed to the closed chain, and the buckets are installed with the possibility of immersion in the tank for lubricating oil at the lower position of the counterweight, and the dimensions of the bucket ensure the flow of lubricating oil from it onto the chain during the reciprocating stroke of the counterweight.

Also new is that the switchable manual drive is mounted on a frame with a retractable support and is made in the form of a self-braking worm pair, the worm wheel of which is mounted on the high-speed shaft of the gearbox, and the worm is installed in the rotation supports of the removed support and is connected to the drive handle for rotation.

Also new is the fact that the support is mounted on the frame with a shaft connecting the gearbox output shaft to the drive sprocket with the possibility of transmitting torque.

Figure 1 shows a side view of the drive of a downhole sucker rod pump.

Figure 2 shows a front view of the drive downhole sucker rod pump.

Figure 3 shows a cross-section EE counterweight.

Figure 4 shows the lower part of the drive borehole sucker rod pump when the counterweight is located below, front view.

Figure 5 shows a section DD.

Figure 6 shows a bucket with a cross section in the area of the hole.

Figure 7 shows a view of B.

On Fig depicts a view of B.

Figure 9 shows a section aa.

A downhole sucker-rod pump drive comprising a housing 2 mounted on a base 1 (see FIG. 1) with a single frame 3 on which a motor 4 is mounted, a gearbox 5, a mechanism placed in the housing 2, which converts the rotational motion into reciprocating and including a driving 6 and the upper 7 sprockets covered by a closed chain 8 (see Figure 2), connected with the carriage 9, connected to the counterweight 10. The counterweight 10 is made in a U-shape (see Figure 3) in cross section and installed in the guides 11 of the housing 2 with the placement of chain 8 (see Figure 2) in its open cavity 12 (see Figure 3) and is connected through a flexible link 13 (see Figure 1) with the suspension node of the rods 14. Moreover, the vertical axis of symmetry 15, 16, 17 (see Figure 2), respectively, of the transforming mechanism, the counterweight 10 and flexible link 13 (see Figure 1) are located in close proximity to one vertical plane 18 (see Figure 2), the upper sprocket 7 is installed in the housing 2 with the possibility of rotation and limited movement along the axis 15 of the conversion mechanism for regulating the chain tension 8, and in the lower part of the housing 2 is made a tank 19 for lubricating oil. In this case, the gearbox 5 (see Figs. 1 and 7) is additionally equipped with a switchable manual drive 20 (see Fig. 7) for rotating the drive sprocket 6 (see Fig. 1). The upper sprocket 7 is configured to have limited axial movement and fixation. The counterweight 10 (see Figure 5) is additionally equipped with removable latches 21, made with the possibility of hanging the counterweight 10 relative to the housing 2 (see Figure 1) in any desired place, and two buckets 22 (see Figure 4) installed from the bottom counterweight 10 on the sides of the closed chain 8 and made with holes 23 (see Fig.6) below in the side wall, directed to the closed chain 8 (see Fig.4). The buckets 22 are installed with the possibility of immersion in the tank 19 for lubricating oil with the lower position of the counterweight 10, and the dimensions of the bucket 22 ensure the flow of lubricating oil from it onto the chain during the reciprocating stroke of the counterweight 10. To ensure this, the dimensions of the bucket can be determined by the following mathematical formulas:

where d is the diameter of the hole 23 in the side wall of the bucket 22, m;

D _i - dividing the diameter of the drive sprocket 6, m;

S - stroke length, m;

ν is the kinematic viscosity of the lubricating oil, m ² / s;

ρ is the density of the lubricating oil, kg / m ³ ;

g is the acceleration of gravity, m ² / s;

n is the number of swings, min ^-1 ;

V is the volume of the bucket cavity above the hole in the side wall, m ³ ;

N - bucket height above the hole in the side wall (distance from the top edge of the bucket to the hole), m

From the formula (1) we derive the formula for determining the height of the bucket above the hole in the side wall (distance from the top edge of the bucket to the hole):

Switchable manual drive 20 (see Fig. 7) is mounted on a frame 3 with a retractable support 24 and is made in the form of a self-braking worm pair, the worm wheel 25 of which is mounted on the high-speed shaft 26 of the gearbox 5, and the worm 27 is installed in the rotation supports 28 of the removed support 24 and connected to the drive handle 29 for rotation.

A support 30 of rotation is mounted on the frame 3 with a shaft 31 connecting the output shaft 32 of the gearbox 5 with the drive sprocket 6 with the possibility of transmitting torque.

On the sides of the counterweight 10 (see FIG. 2) wheels 33 are mounted to reduce friction, which are mounted to interact with the guides 11. On the frame 3 (see FIG. 9) wheels 34 are provided, the eccentric axes 35 of which are located in the bushings 36 installed in frame 3 with the possibility of limited rotation of the eccentric axes 35.

The upper sprocket 7 (see Fig. 8) is made with the possibility of limited axial movement and fixation using guides 37 and fixing bolts 38.

The drive well pump operates as follows.

The drive assembly is installed on the base 1 (see Figure 1) at the wellhead (not shown).

After that, the drive is tuned.

The eccentric axes 35 (see Fig. 9) in the bushings 36 are rotated so that the frame 3 is raised on the wheels 34 above the support 1. Next, the frame 3 is moved on the wheels 34 relative to the support 1 so that the rod suspension assembly 14 (see Fig. 1 ) is installed above the wellhead (not shown) connected in the well (not shown) with a rod string (not shown), the eccentric axes are turned so that the wheels 34 are out of interaction with the base 1, while the frame 3 completely rests on the base 1. Then, the upper sprocket 7 is adjusted (see Fig. 8), for this fixing bolts 38 weaken, shift the axis of the upper sprocket 7 up or down along the axis 15 of the converting mechanism, achieving optimal tension of the chain 11 (see Figure 2), and left or right along the guides 37 (see Figure 8) relative to the axis of the upper sprocket 7, achieving a minimum deviation of the plane of the chain 8 (see Figure 2) from the planes of rotation of the upper 7 and the leading 6 sprockets. Then the fixing bolts 38 (see Fig. 8) are tightened.

Next, prepare the drive to work.

The retractable support 24 (see Fig. 7) is mounted on the frame 3 so that the worm 27 engages with the worm wheel 25, which is mounted on the high-speed shaft 26 of the gearbox 5 after the engine 4. As a result, the disconnected manual drive 20 is ready for operation. Then, by turning the screw handle 29 on the worm 27 in the rotation supports 28 of the retractable support 24, the worm wheel 25 of the high-speed shaft 26 of the gearbox 5 is rotated, as a result of which the counterweight 10 (see FIG. 2) is raised to the upper position and, therefore, lowered through the flexible link 13 rod suspension assembly 14 (see FIG. 1) in the lower position. Connect the suspension assembly of the rods 14 with the wellhead. Using a manual drive 20 lower the counterweight 10 (see Figure 2) to the lower position. Thus, the connection of the drive with the downhole equipment is simplified and does not require the involvement of additional lifting means. By adding, in contrast to 10, the required amount of cargo, the drive is balanced in accordance with the parameters of a particular well, the design of the rod string, the depth of descent and the diameter of the sucker rod pump (not shown), the expected dynamic level and density of the fluid in the well. Lubricating oil is poured into the container 19. Moreover, the required oil volume is much less than that of the closest analogue (see US Pat. No. 4,916959), since the oil tank 19 is not designed to immerse a large carriage 9 into it, but is designed to immerse only relatively small buckets 22 ( see Figure 4) with holes 23 (see Figure 6) with parameters calculated by the formula (2). Then remove the disconnectable manual drive 20 (see Fig.7).

The drive is put into operation.

At each reciprocating stroke in the lower position of the counterweight 10 (see Figure 4), the buckets 22 are immersed in the tank 19 and filled with lubricating oil. During the upward stroke, the oil flows through the holes 23 in the side wall of the buckets 22 in a continuous stream to the closed circuit 8 (see Figure 2), greasing it liberally. Excess oil flows from circuit 8 back to reservoir 19. Abundant lubrication increases the durability of the drive conversion mechanism. Due to the presence of two buckets 22 (see Figure 4) installed symmetrically on both sides of the closed circuit 8, it is possible during operation after a certain time to change the direction of rotation of the drive sprocket 6 by changing the direction of rotation of the engine 5 (see Figure 1) , while always from one of the buckets 22 (see Figure 4), the oil will fall on the moving branch of the closed chain 8 (see Figure 2), providing lubrication along its entire length. Changing the direction of rotation of the engine 5 (see Figure 1) allows to increase the durability of the unilaterally loaded elements (such as the teeth of the gears of the gearbox 4, the teeth of the sprockets 6 and 7, the wheels 33 (see Figure 4) of the counterweight 10, interacting with the guides 11 (see Figure 3), and others) and the drive as a whole. Due to the fact that the chain 8 (see Figure 2) is located in the open cavity 12 (see Figure 3) of the U-shaped counterweight 10, and the vertical axis of symmetry 15, 16, 17 (see Figure 2), respectively the transforming mechanism, the counterweight 10 and the flexible link 13 (see Figure 1) are located in close proximity to the same vertical plane 18 (see Figure 2), parasitic loads on the drive are practically eliminated and, therefore, additional power elements reinforcing the design are not required as well as minimized the cost of energy to overcome these parasites s loads. The presence on the frame 3 (see Fig. 1) of a rotation support 30 with a shaft 31 connecting the output shaft 32 of the gearbox 5 with the drive sprocket 6 with the possibility of transmitting torque, eliminates the runout and inconsistency of the output shaft 32 of the gearbox 5 and the drive sprocket 6, increasing thereby the durability of the gearbox 5 and the conversion mechanism. All this together saves material and energy resources.

For scheduled maintenance, as well as in case of need for repair work, the drive is stopped, the engine 4 (see Figure 1) is turned off, the counterweight 10 (see Figure 2) using a switchable manual drive 20 (see Figure 7) is moved to the desired position, removable latches 21 (see Figure 3), on which the counterweight 10 rests, is inserted into the grooves 39 of the housing 2 (see Figure 1). As a result, the counterweight 10 (see Figure 2) is fixed relative to the housing 2 (see Figure 1). After that, weaken the chain 8 (see Figure 2) and perform the necessary operations. During the assembly of the drive, as well as during maintenance and repair work, check the accuracy of the relative position of the leading 6 (see Figure 1) and the top 7 stars of the conversion mechanism. If necessary, the position of the upper sprocket 7 is adjusted by moving it in the guides 37 (see Fig. 8) until it is aligned with the plane of the sprocket 6 (see Fig. 1), followed by fixing with bolts 38 (see Fig. 8). To dismantle the gearbox 5 (see Figure 1), if it is necessary to repair or replace it, disconnect its output shaft 32 from the shaft 31 of the intermediate rotation support 30, after which nothing prevents the dismantling of gearbox 5. For this operation, the converting mechanism is not disassembled in comparison with analogues required.

During underground well repair by turning the eccentric axes 33 (see Fig. 9), the wheels 32 are moved to the lower position, while the frame 3 is raised by the eccentricity of the axes 33 above the base 1 (see Fig. 1) and using an auxiliary winch (not shown) ) on wheels 32 (see Fig. 9) along the base 1 (see Fig. 1) it is rolled from the wellhead to the required distance. The installation of the drive in the operating position is carried out in the reverse order.

Thus, the proposed design of the drive of a borehole sucker rod pump allows to increase the reliability and durability of the drive due to the guaranteed lubrication of the entire chain and the sprockets interacting with it at any speeds and lengths of its movement, as well as to simplify its maintenance due to the possibility of fixing the counterweight in the housing if necessary temporary disconnecting the circuit from it, simplifying the connection (and disconnection) of the suspension assembly of the actuator rods with the wellhead rod, the possibility of adjusting the position of the driven sprocket and with respect to the leading difficult to install them in a single plane.

Claims (3)

1. A downhole sucker-rod pump drive comprising a motor mounted on a base frame with a housing, a gearbox, a mechanism placed in the housing that converts rotational motion into reciprocating motion and includes a drive and upper sprockets, enclosed by a closed chain connected to a carriage connected to a counterweight , which is made in a U-shape in cross section and installed in the guides of the housing with the placement of the chain in its open cavity and connected through a flexible link with the node suspension rods, and the vertical The axes of symmetry of the conversion mechanism, the counterweight and the flexible link are located in close proximity to one vertical plane, the upper sprocket is mounted in the housing with the possibility of rotation and limited movement along the axis of the conversion mechanism to control the chain tension, and a lubricating oil tank is made in the lower part of the housing, characterized in that the gearbox is additionally equipped with a switchable manual drive for rotating the drive sprocket, and the upper sprocket is made with the possibility of limiting axial displacement and fixation, while the counterweight is additionally equipped with removable clamps, made with the possibility of hanging the counterweight relative to the housing in any desired place, and two buckets mounted below the counterweight on the sides of the closed chain and made with holes from the bottom in the side wall, directed to the chain moreover, the buckets are installed with the possibility of immersion in the tank for lubricating oil at the lower position of the counterweight, and the dimensions of the bucket ensure the flow of lubricating oil from it to chain during the reciprocating stroke of the counterweight. 2. The downhole sucker-rod pump drive according to claim 1, characterized in that the disconnectable manual drive is mounted on a frame with a retractable support and is made in the form of a self-braking worm pair, the worm wheel of which is mounted on the high-speed shaft of the gearbox, and the worm is installed in the bearings of rotation of the outlet support and connected to the drive handle for rotation. 3. The downhole sucker-rod pump drive according to claim 1, characterized in that a rotation support is mounted on the frame with a shaft connecting the gearbox output shaft to the drive sprocket with the possibility of transmitting torque.

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