CN113818838A

CN113818838A - Ultra-long stroke oil pumping ground equipment and dual-machine oil pumping unit applying same

Info

Publication number: CN113818838A
Application number: CN202111034849.7A
Authority: CN
Inventors: 丁蕾; 许丽; 朱西柱; 李立标; 廖永刚; 赵君峰; 祝英俊; 付尧
Original assignee: Qingdao Xinsheng Petroleum Machinery Co ltd
Current assignee: Qingdao Xinsheng Petroleum Machinery Co ltd
Priority date: 2021-09-04
Filing date: 2021-09-04
Publication date: 2021-12-21

Abstract

An ultra-long stroke oil pumping ground device and a dual-machine oil pumping machine using the ground device. The invention discloses an ultra-long stroke oil pumping ground device which comprises a driving mechanism arranged on a tower frame near a wellhead, wherein the driving mechanism comprises a motor, a winding drum driven by the motor to rotate and head sheaves arranged on two sides of the winding drum. The outer wall of the winding drum is provided with two areas, two sets of flexible oil production ropes are wound on the two areas respectively, the two sets of flexible oil production ropes wind around the two head sheaves respectively, and the rotation axes of the winding drum are spaced.

Description

Ultra-long stroke oil pumping ground equipment and dual-machine oil pumping unit applying same

Technical Field

The invention relates to the technical field of mechanical oil pumping ground equipment, in particular to ultra-long stroke oil pumping ground equipment and a dual-machine oil pumping machine using the oil pumping ground equipment.

Background

The traditional oil pumping unit has the defects of short stroke, large leakage, low pump efficiency and the like. On the basis, research and development personnel develop an ultra-long stroke oil pumping mechanism. Known embodiments, represented by publication number CN208236391U, have achieved ultra-long stroke pumping.

The ultra-long stroke oil pumping machine represented by CN111622717A has the advantages that the flexible oil production rope is wound/released by the winding drum, and the plunger pump is driven by the flexible oil production rope, so that the plunger pump realizes a single ultra-long oil pumping stroke of 50-100m, and the oil extraction efficiency is greatly improved.

On the basis of the above, the ultra-long stroke oil pumping is further developed. Specifically, a dual-mode oil extraction machine represented by CN106837253A is produced. Compared with the traditional beam oil extraction machine, the double-machine type ultra-long stroke oil extraction machine has the advantages that the oil extraction efficiency is improved by more than 150%, the electricity saving rate is more than 70-80%, and the double-machine type ultra-long stroke oil extraction machine has a wide application prospect.

However, the known embodiment of CN111622717A does not mention how the problem of driving two sets of production lines by one spool is achieved. In practice, because two sets of flexible production lines are wound on the same winding drum at the same time, how to avoid the mutual interference of the two sets of production lines is a technical problem worthy of attention.

Disclosure of Invention

In view of the above-mentioned drawbacks of the prior art, embodiments of the present invention provide an ultra-long stroke oil pumping surface device and a dual-machine oil pumping unit using the same.

The ultra-long stroke oil pumping ground equipment comprises a driving mechanism arranged on a tower frame near a wellhead, wherein the driving mechanism comprises a motor, a winding drum driven by the motor to rotate and head pulleys positioned on two sides of the winding drum. The outer wall of the winding drum is provided with two areas, two sets of flexible oil production ropes are wound on the two areas respectively, the two sets of flexible oil production ropes wind around the two head sheaves respectively, and the rotation axes of the winding drum are spaced.

Preferably, the spool performs the reverse operations on the first flexible production string and the second flexible production string while rotating.

Preferably, the first flexible production line and the second flexible production line are rolled in or released through the highest point of the winding drum; the highest point of the winding drum is higher than the highest points of the first head sheave and the second head sheave.

Preferably, one of the first flexible production string and the second flexible production string is reeled in or released through the highest point of the reel, and the other of the first flexible production string and the second flexible production string is reeled in or released through the lowest point of the reel; the drum is configured to perform the same operation on the first and second flexible production lines when rotated

Preferably, the first and second head sheaves are arranged to be spaced apart also in the direction of the axis of rotation.

Preferably, the first head sheave and the second head sheave are spaced apart by a distance equal to a distance separating the first flexible production string and the second flexible production string in the direction of the rotation axis.

Preferably, the top end of the tower is provided with a fixed bracket supporting the drum, and the drum is movable relative to the fixed bracket in the rotational axial direction.

Preferably, the outer wall of the drum is formed with a helical rope groove in which the flexible production string is at least partially embedded; the drum is configured to be driven by the motor to move by a width of one rope groove in the rotational axial direction per one rotation by a movement actuator.

Preferably, the winding drum is arranged on the fixed support through a winding drum support, the winding drum is arranged on the winding drum support in a rotating mode, the motor is arranged on the outer side of a first end of the winding drum support in the rotating axial direction, and the moving executing mechanism is located on the outer side of the other second end of the winding drum support in the rotating axial direction.

Preferably, the movement actuator includes:

a drive wheel located outside the second end of the spool support, the drive wheel being coaxial with the spool;

a drive assembly disposed on the spool support, the drive assembly having an input terminal and an output terminal; the input terminal is provided with a driven wheel connected with the driving wheel through a transmission part, and the output terminal is provided with a gear;

and the rack is arranged on the fixed support and meshed with the gear.

Preferably, the transmission assembly is configured as a shaft.

Preferably, the transmission assembly is configured as a reducer.

Preferably, the drive wheel and driven wheel are configured as sprockets.

Preferably, the rope groove spacing of the winding drum is D (mm), the speed ratio of the driving wheel to the driven wheel is i1, the speed ratio of the speed reducer is i2, the number of teeth of the gear is Z, and the pitch of the rack is d (mm); the movement actuator is configured to comply with a parameter setting relationship of D ═ Z × D/(i1 × i 2).

Preferably, the spool is restrained from rotation by a rotation stop mechanism operable.

Preferably, the rotation stopping mechanism comprises a first limiting assembly configured to operatively limit rotation of the spool in a first direction, the first direction being a direction in which the spool releases the first flexible production string.

Preferably, the first limiting assembly includes a first ratchet wheel disposed at the first end of the spool and a first pawl rotatably disposed on the spool support.

Preferably, the first pawl is configured to be operatively switched between a first release position and a first detent position; the first pawl is further configured to disengage the first ratchet wheel when in the first release position to allow the spool a degree of freedom to rotate in the first direction and to cooperate with the first ratchet wheel when in the first anti-rotation position to limit rotation of the spool in the first direction.

Preferably, the rotation stop mechanism includes a second limiting assembly configured to operatively limit rotation of the spool in a second direction opposite the first direction, the second direction being a direction in which the spool releases the second flexible production line.

Preferably, the second limiting assembly includes a second ratchet wheel provided at the second end of the spool and a second pawl rotatably provided on the spool support.

Preferably, the second pawl is configured to be operatively switched between a second release position and a second detent position; the second pawl is further configured to disengage the second ratchet wheel when in the second release position to allow the spool a degree of freedom to rotate in the second direction and to cooperate with the second ratchet wheel when in the second anti-rotation position to limit rotation of the spool in the second direction.

The double-machine pumping unit comprises the ultra-long stroke pumping ground equipment, the tower is positioned between the well heads of the two oil production wells, the oil well pumps are respectively arranged in the two oil production wells, and the two oil well pumps are respectively connected with the two sets of flexible oil production ropes.

The scheme of the embodiment of the invention can avoid the problem of mutual interference of the two sets of flexible oil production ropes, and ensure that one winding drum drives the two sets of oil production ropes to be smoothly realized.

Drawings

Fig. 1 is a schematic diagram of a dual-machine pumping unit according to an embodiment of the present invention;

FIG. 2 is a perspective view of the ultra-long stroke pumping surface unit of FIG. 1;

FIG. 3 is a side view of FIG. 2;

FIG. 4 is a top view of FIG. 2;

fig. 5 is a perspective view of the spool of fig. 2.

Detailed Description

As shown in fig. 2 to 5, the ultra-long stroke pumping surface equipment according to the embodiment of the present invention includes a tower 300 provided near the wellhead and a driving mechanism 400 provided on the tower 300. Wherein the driving mechanism 400 includes a motor 403, a drum 404 driven by the motor 403 to rotate around a rotation line, and a first head sheave 401 and a second head sheave 402 located on both sides of the rotation line.

The outer wall of the drum 404 is configured to include a first region and a second region distributed in the direction of the rotation axis, and the drive mechanism 400 further includes a first flexible production string 405 wound around the first region and a second flexible production string 406 wound around the second region. The first flexible production string 405 and the second flexible production string 406 pass around the first head sheave 401 and the second head sheave 402, respectively, to be guided by the first head sheave 401 and the second head sheave 402.

As shown in fig. 1, the dual pumping unit includes the ultra-long stroke pumping surface equipment of the above embodiment, and the tower 300 is disposed between the wellheads of the first and

second production wells

100 and 200. The first oil well pump 101 and the second oil well pump 202 are respectively arranged in the first oil well 100 and the second oil well 200, and the first oil well pump 101 and the second oil well pump 202 are respectively connected with the first flexible production rope 405 and the second flexible production rope 406.

In this embodiment, the tower 300 is provided at the top end thereof with a fixed bracket 600 for supporting the drum 404, the drum 404 is movably provided on the fixed bracket 600 by the drum bracket 500, and the drum 404 is rotatably provided on the drum bracket 500.

As shown in fig. 4, the bottom of the reel stand 500 is provided with a support roller 501, and the fixed stand 600 is provided with a track for the support roller 501 to travel. Thereby, the spool 404 is smoothly moved. Further, at least one side of the roll stand 500 may be further provided with a guide roller 502 for cooperating with a guide rail on the fixing stand 600 to guide the movement of the roll 404.

The outer wall of the drum 404 is formed with a helical rope groove for the flexible production line to be at least partially embedded, so as to ensure the stable arrangement of the flexible production line. In the direction of the axis of rotation, the two sets of

flexible production lines

405, 406 are spaced. Correspondingly, the two

head pulleys

401, 402 are spaced apart in the direction of the axis of rotation.

The drum 404 is driven by the movement actuator 700 to be movable in the rotational axial direction with respect to the fixed bracket 600. Wherein the motor 403 is disposed outside a first end of the roll stand 500 along the rotational axial direction, and the movement actuator 700 is disposed outside the other second end of the roll stand 500 along the rotational axial direction.

As shown in fig. 1, 4 and 5, the movement actuator 700 includes a driving wheel 701 located outside the second end of the spool support 500, a transmission assembly 702 provided on the spool support 500, and a rack 703 provided on the fixed support 600. Specifically, the spool support 500 includes two ribs 503 arranged in the rotation axis direction and a lock member 504 locking the two ribs 503, and the spool 404 is provided between the two ribs 503 through a rotation axis. The motor 403 is fixed to the outer side of one of the ribs 503, and the other end of the shaft 407 extends to the outer side of the other rib 503.

The driving wheel 701 is disposed coaxially with the drum 404, and specifically, the driving wheel 701 is connected to the other end of the rotating shaft 407. Thus, the drive wheel 701 rotates in synchronization with the drum 404. The transmission assembly 702 has an input terminal 7021 and an output terminal 7022, the input terminal 7021 is provided with a driven wheel 704 connected to the driving wheel 701 through a transmission member 706, the output terminal 7022 is provided with a gear 705, and the rack 703 is engaged with the gear 705.

In this embodiment, the transmission assembly 702 may be a shaft structure, and two ends of the shaft respectively constitute the input terminal 7021 and the output terminal 7022. However, the transmission assembly 702 is preferably a speed reducer, and an input value and an output shaft of the speed reducer constitute the input terminal 7021 and the output terminal 7022, respectively.

The drive wheel 701 and the driven wheel 704 may be sprockets and the transmission 706 may be a chain, respectively. Of course, the driving wheel 701 and the driven wheel 704 may be synchronous wheels or belt wheels, and the transmission member 706 is correspondingly synchronous belt or belt.

Thus, during the rotation of the drum 404 driven by the motor 403, the driving wheel 701 is synchronously driven to rotate, the driving gear 705 drives the rotation of the driving wheel through the transmission member 706 and the transmission assembly 702, and the drum support 500 is driven to move along a straight line by the engagement of the driving gear 705 and the rack 703, so as to carry the drum 404 to move together.

Thus, through one set of power assembly, the two sets of oil pumping mechanisms are driven to pump oil, and meanwhile, the winding drum 404 can be driven to perform translational motion, so that the flexible

oil production ropes

405 and 406 can be always aligned with the head sheaves 401 and 402 without eccentric wear. Therefore, the service life of the flexible

oil production ropes

405 and 406 is prolonged to the maximum extent while high oil production efficiency is obtained.

It should be understood that the movement actuator 700 should not be limited to the above-described embodiments. In other alternative embodiments, the movement actuator 700 may have other alternative configurations, such as a ball screw, hydraulic rod, electric telescopic rod, etc.

It is noted that to avoid the eccentric wear of the

flexible production lines

405, 406, the drum 404 is driven by the motor 403 to move by the width of one line groove in the axial direction of rotation by the moving actuator 700 for each rotation. In this way, the angle between the

flexible production lines

405, 406 and the axis of the drum 404 is always kept small, for example less than 0.3 °, even smaller, or 0 °. In this way, it is ensured to the utmost that both sets of

flexible production lines

405 and 406 can always keep aligned with the corresponding head sheaves 401 and 402 without eccentric wear due to too large deflection angles.

When the spool 404 is driven to rotate in the first direction L1 (counterclockwise as viewed in fig. 3), the movement actuator 700 may move the spool 404 in the horizontal first translation direction F1 (as viewed in fig. 5) by driving the spool support 500. As described below, the first flexible production line 405 and the second flexible production line 406 are driven by the drum 404 to have opposite operations. Assuming that in this case the first flexible production string 405 is wound and the second flexible production string 406 is released, the winding of the first flexible production string 405 and the release of the second flexible production string 406 are performed in the same first translation direction F1.

Likewise, when the spool 404 is driven to rotate in a second direction L2 (clockwise as viewed in fig. 3) opposite the first direction L1, the movement actuator 700 may cause the spool 404 to move in a second horizontal translation direction F2 (as viewed in fig. 5) by driving the spool support 500. Assume in this case that the first flexible production string 405 is released and the second flexible production string 406 is wound. The releasing of the first flexible production string 405 and the winding of the second flexible production string 406 take place in the same second direction of translation F2.

As shown in fig. 3, when the driving mechanism 400 located at the middle of the top end of the tower 300 winds the flexible production string indicated on the left side and unwinds the flexible production string indicated on the right side, the whole driving mechanism 400 moves synchronously along the vertical direction indicated in the figure, so as to ensure that the flexible production strings on the left and right sides are always aligned with the center of the head sheave at the winding or unwinding access point of the winding drum 404.

In this embodiment, the rope groove pitch of the winding drum 404 is d (mm), the speed ratio between the driving wheel 701 and the driven wheel 704 is i1, the speed ratio of the speed reducer is i2, the number of teeth of the gear 705 is Z, and the pitch of the rack 703 is d (mm). As described above, the movement actuator 700 satisfies the parameter setting relationship D ═ Z × D/(i1 × i2), and satisfies the above synchronization relationship of the roll 404: for each revolution of the drum 404, the flexible production line is displaced relative to the drum 404 by a distance D of one of the rope grooves.

As described above, the oil recovery operation can be performed by the bidirectional rotation of the drum 404. Therefore, when the oil recovery operation is required to be stopped for maintenance of equipment or the like, the rotation of the spool 404 in both directions is required to be restricted. In view of this, a rotation stop mechanism is provided for operatively limiting rotation of the spool 404.

As shown in fig. 1, 2, 4 and 5, in an alternative embodiment, the rotation stopping mechanism includes a first limiting assembly 800 for limiting the rotation of the spool 404 in the first direction L1, the first limiting assembly 800 includes a first ratchet 801 disposed at a first end of the spool 404 and a first pawl 802 rotatably disposed on the spool support 500.

Wherein the first pawl 802 is operable to shift between a first release position and a first detent position. When in the first release position, the first pawl 802 is disengaged from the first ratchet wheel 801 and the spool 404 has freedom to rotate in a first direction L1. In the first detent position, the first pawl 802 engages the first ratchet wheel 801 and the spool 404 is restrained from rotating in the first direction L1.

Similarly, the anti-rotation mechanism further includes a second limiting assembly 900 operable to limit rotation of the spool 404 in the second direction L2, the second limiting assembly 900 including a second ratchet 901 disposed at a second end of the spool 404 and a second pawl 902 rotatably disposed on the spool support 500.

The second pawl 902 is operable to shift between a second release position and a second detent position. When in the second release position, the second pawl 902 is disengaged from the second ratchet 901, and the spool 404 has a degree of freedom to rotate in the second direction L2; and in the second detent position, the second pawl 902 engages the second ratchet wheel 901 and rotation of the spool 404 in the second direction L2 is limited.

The first known embodiment, represented by publication numbers CN207999232U and CN304717482S, discloses a twin well oil recovery scheme. However, the drums of the two first known embodiments are fixedly arranged (i.e. cannot move in the direction of their rotation axis) and the drums are arranged on the ground. With such a design, there are a series of irreconcilable structural contradictions.

Specifically, the winding drum is arranged on the ground, the head sheaves on two sides are arranged at the top end of the tower, and the height of the winding drum is lower than that of the head sheaves on two sides. Then, the two sets of flexible oil extraction ropes apply upward pulling force to the winding drum, and the phenomenon similar to the radish pulling phenomenon is formed. Thus, the fixing strength of the reel to the ground is greatly challenged, and the problem that the reel is pulled up and separated from the ground due to the fact that the fixing strength of the reel to the ground is reduced after long-time operation is easily caused. Thus, the safety and reliability of the known embodiment is a great problem.

However, even so, the two first known embodiments described above do not consider the design of the drum at the top end of the tower. The reason is that: as explained in the background of the second known embodiment of publication No. CN111622717A, in order to ensure that the flexible polish rod works properly on the drum, it is necessary to ensure that the deviation angle α of the flexible rope and the central axis of the steering head sheave is small, which requires a relatively long distance between the steering head sheave and the drum.

It can be seen that if the drum of the two first known embodiments is placed at the top of the tower, the problem of "picking up radishes" of the drum can be solved. However, this results in a short distance between the winding drum and the two steerable head sheaves, which in turn causes the problems of large deflection angle and severe wear of the flexible rope as described in the second known embodiment.

In contrast, the embodiments of the present invention can better solve the problems of the two known embodiments.

Specifically, referring to fig. 1 and 3, in the present embodiment, a winding drum 404 is provided at the top end of the tower 300, the highest point of the winding drum 404 is higher than the highest points of the first and

second day wheels

401 and 402, and the first and second

flexible production strings

405 and 406 are wound or released through the highest point of the winding drum 404.

Since the drum 404 in the embodiment of the invention can eliminate the decentration of the flexible production line 405 by moving axially, the conventional solution of increasing the distance between the drum 404 and the head pulleys 401 and 402 is not necessary, which provides the condition for the drum 404 to be arranged at the top end of the tower 300, and the design can greatly reduce the base area of the whole production mechanism.

Since the winding drum 404 is disposed at the top end of the tower 300, the

flexible production lines

405 and 406 on both sides are wound into the winding drum 404 or released from the winding drum 404 by taking the highest point of the winding drum 404 as a tangent point. In this way, the

flexible production lines

405, 406 on both sides exert a vertical downward force on the drum 404, which ultimately acts on the ground through the tower 300. Therefore, the whole ground equipment is firmly fixed on the ground, and the stability of the system structure is excellent.

It is noted that in the above description of the embodiment of the present invention, both sides of the

flexible production string

405, 406 are wound or released from the highest point of the winding drum 404. Additionally, since the two sets of

flexible production lines

405, 406 are driven by the same spool 404, the spool 404 performs the opposite operation for the two sets of

flexible production lines

405, 406 when rotating.

Specifically, when the drum 404 rotates to wind the first flexible production string 405, the second flexible production string 406 is released. Correspondingly, the first pump 101 is in the up stroke and the second pump 202 is in the down stroke.

Similarly, when the drum 404 rotates to release the first flexible production string 405, the second flexible production string 406 is wound. Correspondingly, the first pump 101 is in the down stroke and the second pump 202 is in the up stroke.

The twin wells of embodiments of the present invention also have a more load balancing effect than a single well. As described above, both

pumps

101, 202 exert a lateral force on the drum 404. Although the strokes of the two

pumps

101, 202 are opposite, the pump in the up stroke exerts a large lateral force on the drum 404, and the pump in the down stroke exerts a small lateral force on the drum 404, the pump in the down stroke can still provide at least partial compensation of the lateral load acting force on the drum 404, which has a certain gain effect on the load balance of the drum 404, and is beneficial to the structural stability of the drum 404.

In addition, by adopting the scheme that the winding drum 404 winds one flexible production line and releases the other flexible production line, when one oil well pump ascends to pump oil, the other oil well pump descends, and the descending oil well pump can be indirectly used as a counterweight of the motor 403, so that the load of the motor 403 is reduced to a certain extent, and therefore, the comprehensive work of the motor 403 for driving the winding drum 404 is less than 70% of the work of a single oil well pump when the winding drum 404 rotates every time. Thus, the output power of the motor 403 is small, and the energy consumption is greatly reduced.

In addition, since the spool 404 drives the dual pumping unit, the spool 404 pumps oil regardless of the direction (L1, L2) in which it rotates. That is, both the forward and reverse rotation of the motor 403 do work in pumping, and there is no idle condition without pumping oil. Therefore, the oil pumping efficiency is higher, and the oil pumping amount is increased under the same energy consumption, so that the energy consumption utilization rate is improved, and the energy consumption is reduced indirectly.

It is noted that the spool 404 is not limited to the embodiment described above in which the two flexible production lines are reversed when both flexible production lines are reeled in or released from the highest point of the spool 404. In practice, when both flexible production lines are reeled in and released from the highest point of the reel 404, both flexible production lines may also be reeled in and released simultaneously, depending on the fixed position of the two flexible production lines on the reel 404.

It is emphasized, however, that the embodiment described above in which the spool 404 drives one flexible production line into the spool and the other flexible production line out of the spool can significantly reduce rotational power and energy consumption compared to this embodiment.

Through field experiment verification, the data comparison between the dual-machine ultra-long stroke type pumping unit of the embodiment of the invention and the traditional beam pumping unit is as follows:

double-machine beam-pumping unit

Power of the motor 403: 22Kw

Stroke: 3m

Punching times: 4n/min

Daily liquid yield: 30t/d

Daily power consumption: 309Kw h

The system efficiency is as follows: 11.3 percent of

Double-machine ultra-long stroke oil pumping machine

Power of the motor 403: 22Kw

Stroke: 46m

Punching times: 6n/h

Daily liquid yield: 33t/d

Daily power consumption: 42 Kw.h

The system efficiency is as follows: 44.6 percent

As is apparent from the comparison, by adopting the scheme of the embodiment of the invention, the energy consumption is greatly reduced under the condition of obtaining extremely high oil pumping efficiency improvement.

In addition, the oil pumping surface equipment provided by the embodiment of the invention has the advantage of small occupied area, and is particularly suitable for platform wells (namely, one platform can realize the production of a plurality of wells at the same time). Specifically, a general beam pumping unit includes a base block and occupies a large area. The main components of the pumping surface equipment of the present embodiment are supported by the tower 300 off the ground, so that the fixing bracket 500 with a large area or size can be lifted off the ground. Thus, the main structure of the floor space is only the legs of the tower 300, which greatly reduces the floor space.

Further, the dual-motor oil pumping unit of the embodiment of the invention has lower requirements on dual wells. Specifically, the conventional pumping unit with one machine and two wells requires that the two wells are on the same plane, and the flexible

oil production ropes

405 and 406 adopted by the pumping unit with two machines of the embodiment have certain flexibility, so that the pumping unit can adapt to the dislocation of the two wells on the horizontal plane. Therefore, the requirements of the double pumping unit degree and the double well position of the embodiment are relatively loose, and the application range is wider.

Claims

1. An ultra-long stroke pumping surface unit comprising: the driving mechanism is arranged on the tower; wherein:

the drive mechanism includes: the winding drum is driven by the motor to rotate around a rotating axis, and a first head sheave and a second head sheave are positioned on two sides of the rotating axis;

the outer wall of the drum is configured to contain a first region and a second region distributed along the direction of the rotation axis;

the drive mechanism further includes: a first flexible production string wound around the first drive and a second flexible production string wound around the second drive;

the first flexible production line bypasses the first head sheave, and the second flexible production line bypasses the second head sheave;

the first flexible production line is spaced from the second flexible production line in the direction of the axis of rotation.

2. The very long stroke pump jack apparatus of claim 1 wherein the drum is positioned at the top of the tower with a peak height that is higher than the peaks of the first and second head sheaves.

3. The surface oil pumping apparatus of claim 2, wherein the first and second flexible production lines are each reeled in or released through the highest point of the reel.

4. The very long stroke oil well surface equipment of claim 2 wherein the spool is configured to reverse the operation of the first and second flexible production lines when rotated.

5. The very long stroke oil well surface equipment of claim 1 wherein the first and second head sheaves are configured to be spaced apart in the direction of the axis of rotation as well, and the first and second head sheaves are spaced apart in the direction of the axis of rotation by a distance equal to the distance that the first and second flexible production lines are spaced apart in the direction of the axis of rotation.

6. The very long stroke oil well surface equipment of claim 1 wherein the top end of the tower is provided with a fixed support that supports the drum, the drum being movable relative to the fixed support in the axial direction of rotation.

7. The very long stroke oil well surface equipment of claim 6 wherein the outer wall of the drum is formed with a helical rope groove in which the flexible production string is at least partially embedded; the drum is configured to be driven by the motor to move by a width of one rope groove in the rotational axial direction per one rotation by a movement actuator.

8. The very long stroke oil well surface equipment of claim 1 wherein the spool is operatively restrained from rotation in a first direction by a first restraining assembly, the first direction being the direction in which the spool releases the first flexible production string.

9. The very long stroke oil well surface equipment of claim 8 wherein the spool is operatively restrained from rotation in a second direction opposite the first direction by the second restraining assembly, the second direction being the direction in which the spool releases the second flexible production string.

10. A dual pumping unit comprising: the ultralong stroke pump surface equipment of any one of claims 1 to 9, the tower being configured to be positioned between a first production well and a second production well, the first and second production wells having a first pump and a second pump therein, respectively, the first and second pumps being connected to first and second flexible production lines, respectively.