CN111878012B

CN111878012B - Closed elevator suitable for various pipe diameter specifications

Info

Publication number: CN111878012B
Application number: CN202010812726.0A
Authority: CN
Inventors: 田亚楠; 朱可; 王新明; 吴敬华; 范竹刚
Original assignee: Wuxi Zhihan Energy Technology Equipment And Service Co ltd
Current assignee: Wuxi Zhihan Energy Technology Equipment And Service Co ltd
Priority date: 2020-08-13
Filing date: 2020-08-13
Publication date: 2023-01-13
Anticipated expiration: 2040-08-13
Also published as: CN111878012A

Abstract

The invention relates to a closed elevator which comprises a shell and a clamping mechanism for clamping oil pipes, wherein the clamping mechanism comprises a plurality of clamping blocks which are arranged at intervals along the circumferential direction of the shell, the clamping blocks can be driven to a plurality of different working positions through an actuating mechanism, and the clamping blocks respectively clamp the oil pipes with different pipe diameters at the plurality of different working positions. The closed elevator can be simply and reliably operated automatically to realize the lifting operation of oil pipes with different pipe diameters under the condition of not replacing the whole elevator, thereby improving the operation efficiency and the operation safety.

Description

Closed elevator suitable for various pipe diameter specifications

Technical Field

The invention relates to the field of petroleum well repairing operation equipment, in particular to a closed elevator for lifting (or lowering) an oil pipe.

Background

It is well known that an elevator is an important component in well servicing operations. In workover operations, it is often necessary to effect tripping of the tubing with the aid of an elevator system. However, due to the difference in the specifications (diameter sizes) of the oil pipes, a series of elevators with different specifications are usually designed to be matched to accommodate the oil pipes with different specifications. Research shows that most of the elevators used in the market can only adapt to the diameter of a single-specification oil pipe. Therefore, when workover treatment is carried out, operators need to carry the elevators with various specifications at one time so as to adapt to oil pipes with different diameters by replacing the elevators with different specifications conveniently in the operation process, the automation degree of the whole operation is low, the manual operation intensity is high, the operation efficiency is low, and meanwhile, the field operation environment has certain risks, and the safety of oilfield operation is affected.

Improved elevator systems are known in the art. For example, chinese patent application CN104563915a discloses a hydraulic elevator with an opening and closing indication, which proposes to adapt to clamping and lifting of oil pipes with different pipe diameters by replacing the model of a refill located in the elevator, thereby avoiding the tedious process of replacing the elevator main body and simplifying the operation process of replacing the whole elevator for oil pipes with different specifications.

Chinese patent application CN203035129U discloses an oil pipe elevator which realizes adaptation to oil pipes of different pipe diameter specifications by being provided with replaceable movable crescents having different inner diameters so as to reduce the trouble of replacing the elevator.

US patent application US4035012a discloses a dual elevator that accommodates tubing of different pipe diameters by mating a series of variable bore liners.

However, the above-mentioned known elevator systems in the prior art do not achieve "one-crane-multiple-use" in a complete sense, and although these elevator structures can avoid the operation of replacing the elevator main body due to different pipe diameters, they still need to be matched with a series of elevator accessories (such as the bushing, the movable crescent or the bush in the above-mentioned schemes) with different specifications, so that in the actual operation process, when the elevator is taken off and put down for different oil pipes, the automation degree is still low, and manual operation is involved, the working efficiency is low, and there is a certain operation risk.

Disclosure of Invention

The present invention is therefore based on the background and aims to provide a closed elevator which enables the tripping of oil pipes of various pipe diameters by simple and reliable automated operation without the need to replace the entire elevator.

The invention provides a closed elevator which comprises a shell and a clamping mechanism for clamping an oil pipe, and is characterized in that the clamping mechanism comprises a plurality of clamping blocks which are arranged at intervals along the circumferential direction of the shell, the clamping blocks can be driven to a plurality of different working positions through an actuating mechanism, and the clamping blocks respectively clamp the oil pipes with different pipe diameters at the different working positions.

Advantageously, the closed elevator further comprises a detection mechanism for detecting and confirming entry of a tubing into the housing, the actuation mechanism actuating the plurality of dogs to move to an operating position matching a pipe diameter of the tubing in response to a confirmation signal from the detection mechanism.

Advantageously, the catch mechanism further comprises a plurality of guide blocks arranged in the housing at intervals in a circumferential direction of the housing to provide a movement guide for the plurality of cartridges, each of the guide blocks having an inclined guide surface to guide the movement of the corresponding cartridge in an inclined direction on the inclined guide surface.

Advantageously, the catch mechanism further comprises a rotary plate located below the guide block, one or more projection groups are provided at intervals in a circumferential direction on an end surface of the rotary plate opposite to the guide block, and the number of projections included in each projection group is the same as the number of the cartridges so that each projection can support a corresponding one of the cartridges.

Advantageously, the closed elevator further comprises a rotation cylinder driving a drive gear engaging teeth provided on the outer periphery of the rotating disc, thereby driving the rotating disc to rotate to different angles to allow the plurality of cartridges to abut against the end face of the rotating disc or against the corresponding plurality of protrusions on the end face.

Advantageously, the actuating mechanism comprises a plurality of hydraulic rams, each said dog being coupled to a vertically movable piston rod of a corresponding one of the hydraulic rams for lifting movement therewith.

Advantageously, the closed elevator is further provided with a synchronizing ring moving together with the piston rod and the plurality of blocks, the synchronizing ring is provided with a plurality of through grooves extending along the radial direction at intervals along the circumferential direction, each block comprises a bayonet lock, the bayonet lock is received in the corresponding through groove of the synchronizing ring and is axially limited in the through groove through a head part of the bayonet lock; when the clamping blocks move up and down along with the piston rod, the clamping pins can move in the through grooves along the radial direction, and therefore the synchronous movement of the clamping blocks is achieved.

Advantageously, each of said guide blocks comprises a fixed portion having a first inclined guide surface, at least one slidable portion located within said fixed portion and a compression spring located between said fixed portion and said at least one slidable portion, said at least one slidable portion having a second inclined guide surface which, in the natural position of said compression spring, exceeds said first inclined guide surface in a radial direction and which, when said at least one slidable portion is fully embedded within said fixed portion against the elastic force of said compression spring, is flush with said first inclined guide surface.

Advantageously, the detection mechanism comprises a sensing plate intended to come into contact with and be pushed by the oil pipe entering the casing, a sensor to determine, on the basis of the movement of the sensing plate, that the oil pipe has entered the inside of the casing and to send a confirmation signal, and a return spring intended to return the sensing plate to the original position.

Advantageously, the tubing comprises a tubing body having a first diameter and a collar portion having a second diameter, the second diameter being greater than the first diameter, the collar portion being intended to rest on the plurality of dogs.

Advantageously, the closed elevator comprises a pilot member having a tapered opening coaxially disposed below the rotary disc, the tubing extending through the tapered opening and through a central opening of the rotary disc into the housing.

Advantageously, the closed elevator comprises a lifting lug for connection with a travelling block hook and a connecting rod for a soft guide rail for providing guidance in the lifting operation of the tubing.

By adopting the closed elevator, the lifting operation of oil pipes with different specifications can be met, the automatic matching of the elevator and the oil pipes is realized through power, the complex operation of manually replacing the elevator is omitted, the closed elevator can be applied to a workover rig, the automation and intelligence level of the workover rig is improved, the operation efficiency is improved, and the operation safety is improved.

Drawings

The above and other features and advantages of the present invention will become more readily understood from the following description with reference to the accompanying drawings, in which:

figure 1 illustrates a perspective view of a closed elevator according to an embodiment of the present invention from two different angles;

fig. 2 is a cutaway schematic view showing an internal structure of a closed elevator according to an embodiment of the present invention;

FIG. 3 schematically illustrates, in partial cross-sectional view, the mating relationship between a tubing extending into the housing and a cartridge in the closed elevator;

FIG. 4 shows in perspective and top plan view the meshing relationship of a drive gear driven by a rotary cylinder with a rotary plate disposed at the bottom of a closed elevator;

figure 5 shows in cross-section an advantageous form of construction of the guide blocks included in the closed elevator according to an embodiment of the invention;

figure 6 shows a top view of a closed elevator according to an embodiment of the present invention; and

figure 7 illustrates another top view of the closed elevator according to an embodiment of the present invention with portions of the structure removed to more clearly show the positional relationship between the base portion of the closed elevator and the hydraulic cylinders.

Detailed Description

The present invention will be described in further detail with reference to the following drawings and specific examples. Descriptions of orientations such as "upper", "lower", "top", "bottom", "inner", "outer", "radial", "axial", and the like that may be used in the following description are for convenience of description only and are not intended to limit the inventive concepts in any way unless otherwise specified. In addition, terms such as "first," "second," and the like, which are used hereinafter to describe elements of the present application, are used merely to distinguish the elements, and are not intended to limit the nature, sequence, order, or number of the elements.

As mentioned in the background, an elevator is mainly an important component of a workover operation, and can be generally divided into an open elevator and a closed elevator in terms of structural form. The invention relates to a closed elevator which can be suitable for oil pipes with various pipe diameters and specifications and can be driven between an open state and a closed state through hydraulic power. This closed elevator can be driven in order to form the accommodation space that the oil feed pipe of unidimensional passes through to the adaptation is in the oil pipe that has multiple pipe diameter specification, thereby finally drives oil pipe and accomplishes the operation of getting up down.

Figure 1 shows a closed elevator 1 according to an embodiment of the invention. The closed elevator 1 comprises a shell 2; a lifting lug 3 for connection with a carriage hook (not shown); a connecting rod 4 for a soft guide rail for providing guidance in the lifting operation of the oil pipe; and a clamping mechanism which is arranged in the closed elevator and is suitable for clamping oil pipes 5 with different pipe diameters. The catch mechanism comprises a plurality of dogs 6 arranged evenly spaced in the circumferential direction of the housing 2, which dogs 6 can be driven to a plurality of different operating positions via the actuating mechanism. As shown in fig. 1, the actuating mechanism is preferably a hydraulic ram 7, each hydraulic ram 7 being arranged in a corresponding recess 8 cut in the outer edge of the base portion 15 of the closed elevator 1, which recess 8 may have a U-shaped cross-section (see in particular fig. 7). The top end of a piston rod of the hydraulic oil cylinder 7 is fixedly connected with the clamping block 6, so that the piston rod can drive the clamping block 6 to move together.

It will be appreciated that each of the different operating positions that the blocks 6 can reach corresponds to a gauge of pipe diameter. In the following description, the present invention will be described in detail mainly in the structural form of an exemplary closed elevator including three cartridges, but of course, other numbers of cartridges are possible as long as the technical solution of the present invention can be implemented.

As shown in fig. 1 and 2, three guide blocks 9 are arranged in the housing 1 at regular intervals in the circumferential direction of the housing to provide movement guide for a corresponding number of the latch 6, each guide block 9 having an inclined guide surface to guide the movement of the latch 6 in the inclined direction on the guide surface. Referring particularly to fig. 2, each of the latch blocks 6 is coupled to a piston rod end of each of the hydraulic cylinders 7, which is movable in a vertical direction, respectively, so as to be movable up and down together with the piston rod. When the hydraulic oil cylinder 7 actuates the piston rod to drive the fixture block 6 to move upwards along the inclined guide surface of the guide block, the accommodating space which is defined by all the fixture blocks and can be used for oil pipes to pass through is enlarged, and when the maximum position is reached, the closed elevator is in an open state; conversely, when the block 6 moves downwards along the inclined guide surface of the guide block 9, the accommodating space will gradually become smaller until the accommodating space is matched with the oil pipe 5 extending into the shell, namely the closed state of the closed elevator.

According to an advantageous embodiment, the closed elevator 1 is further provided with a synchronizing ring 10 moving together with the piston rod and the block 6, as shown in fig. 1. The synchronizing ring 10 is provided with three through grooves 11 (for example, in the form of kidney-shaped holes shown in fig. 6) extending in the radial direction at intervals in the circumferential direction, and each latch 6 includes a detent 12, and the detent 12 is received in the corresponding through groove 11 of the synchronizing ring 10 and is axially retained in the through groove 11 by the head of the detent 12. In this way, when the three latch blocks 6 and the synchronizing ring 10 move up and down along with the piston rod, the bayonet 12 can move back and forth in the through groove 11 along the radial direction, so that the synchronism of the movement of all the latch blocks 6 can be ensured. Because the fixture blocks 6 are intended for clamping the pipe body of the oil pipe 5, the maximum load from the oil pipe is borne, if the motions of the fixture blocks 6 are asynchronous, the stress of each fixture block may be uneven, and the fixture block with the largest stress risks being damaged. However, this problem is effectively avoided by the provision of the above-described synchronizer ring.

As will be appreciated by those skilled in the art, the tubing 5 typically includes a tubing body 5a having a first diameter and a collar portion 5b having a second diameter greater than the first diameter. In the closed state of the closed elevator, the oil pipe body 5a is clamped by the three clamping blocks 6 together, and the coupling part 5b is placed on or supported by the three clamping blocks 6, so that the oil pipe can move up and down along with the closed elevator 1, and the lifting operation of the oil pipe is completed.

Since the dog 6 will be subjected to excessive loads from the tubing during tripping, in order to avoid failure of the dog due to too much force, a rotating disc 13 is advantageously provided below the guide block 9. When the fixture blocks 6 are driven by the hydraulic oil cylinder 7 to be in contact with the pipe body of the oil pipe with a specific pipe diameter, all the fixture blocks 6 abut against the rotating disc 13 (at the moment, the fixture blocks are descended in place), so that the load from the oil pipe can be transmitted to the whole elevator through the rotating disc 13, and a better stress condition is provided for the fixture blocks.

Particularly advantageously, one or more groups of projections are provided at intervals in the circumferential direction on the end face of the rotary disk 13 opposite to the guide block 9, each group of projections comprising the same number of projections as the number of the latch blocks 6. As shown in fig. 4, a set of protrusions is provided on the rotary disk 13, and three protrusions 14 abut against the corresponding latch 6. For example, during actual operation, if an oil pipe with a smaller first pipe diameter is operated, the fixture block 6 will eventually descend to abut against the end face of the rotating disk 13, thereby achieving load transmission. However, if an oil pipe having a larger second pipe diameter is operated, the latch 6 will eventually abut against the three protrusions 14 on the end face of the rotating disk, thereby achieving the transmission of the load. Of course, although only one set of protrusions is shown in FIG. 4, to match more pipe diameters, the number of sets of protrusions may be increased accordingly, with the height of the protrusions of each set of protrusions also varying accordingly. The purpose of these protrusions is to compensate for the height difference between the cartridge 6 and the rotating disc 13 when holding oil pipes of different calibers. When clamping a pipe diameter with a smaller specification, the protrusion with a smaller height is selected, and when clamping a pipe diameter with a larger specification, the protrusion with a larger height is selected.

In order to achieve an automated matching between the rotary disk 13 and the cartridge 6. The closed elevator 1 further comprises a rotation cylinder 16, which rotation cylinder 16 drives a driving gear 17, which driving gear 17 engages with teeth 18 provided on the outer circumference of the rotating disc 13 to drive said rotating disc 13 to rotate by different angles according to different pipe diameter specifications, thereby allowing said block 6 to abut against the end surface of the rotating disc 13 or against corresponding protrusions in a specific set of protrusions.

According to an advantageous embodiment, as shown in fig. 5, the guide block 9 may have a double-layered structure including a fixed portion 9a, a slidable portion 9b, and a compression spring 9c between the fixed portion 9a and the slidable portion 9 b. The fixed portion 9a has a radial groove 19, and the slidable portion 9b is capable of being disposed in the radial groove 19 and capable of sliding therein against the elastic force of the compression spring 9c. The fixed part 9a has a first inclined guide surface 20 and the slidable part 9b has a second inclined guide surface 21, which second inclined guide surface 21 in the natural position of the compression spring exceeds said first inclined guide surface 20 in the radial direction and is flush with said first inclined guide surface when the slidable part is fully embedded into the fixed part against the spring force of said compression spring.

For example, when an oil pipe with a smaller pipe diameter is operated, the fixture block 6 can slide obliquely downwards along the second inclined guide surface 21 of the slidable part to the bottom of the guide block, at this time, the fixture block 6 clamps the pipe body of the oil pipe, and the fixture block 6 abuts against the rotating disc; when an oil pipe with a larger pipe diameter is operated, the fixture block 6 can slide obliquely downwards along the second inclined guide surface 21 of the slidable part at the beginning, before the fixture block descends to the bottom of the guide block, the fixture block 6 is contacted with the pipe body in the horizontal direction, and in the subsequent propelling process of the fixture block, the slidable part resists the elastic force of the compression spring and is extruded towards the inside of the fixed part 9a through the fixture block, so that the slidable part 9b enters the fixed part 9a, at the moment, the fixture block 6 can continuously descend along the first inclined guide surface 20 of the fixed part and finally reaches the bottom of the guide block, and at the moment, the fixture block 6 abuts against the rotating disk. After the work is completed, the slidable portion 9b is returned to the original position by the compression spring 9c. It is envisaged that the guide block may be designed to have a more layered structure that can be nested within each other, wherein the more layered structure comprises a fixed portion and a plurality of slidable portions, with a compression spring disposed between each two layered structure, such that it is possible to accommodate oil pipes of more pipe diameters by nesting one layer after another as in the manner of operation of the guide block with a two layered structure described above. In this embodiment, the rotating disk may be stationary and no protrusions are provided on the end face of the rotating disk. Of course, the protrusions for height compensation provided on the rotating disc in the previously discussed embodiments may also be used in combination with the guide blocks having a double-layer or even more-layer structure in the present embodiment, thereby being suitable for a wider range of pipe diameter specifications.

Next, how to use the closed elevator to lift oil pipes with different pipe diameters will be described in detail. Before the closed elevator 1 is used for driving the oil pipe 5 to lift and lower, a detection mechanism is used for executing detection operation so as to determine whether the oil pipe enters the shell of the elevator. As shown in fig. 2, the detection mechanism generally includes a sensing plate 22, a sensor 23, and a return spring 24.

Specifically, the closed elevator 1 is moved by the power provided by the driller's module via the lifting lug 3 attached to the hook of the traveling block on the closed elevator 1, the tubing is aligned and then allowed to extend into the closed elevator housing 2 through the tapered opening 26 of the pilot 25 in the closed elevator and through the central opening 27 of the rotating disc 13 coaxially arranged above the pilot 25 (see fig. 2 and 3) until the upper end of the tubing contacts the sensing plate 22 and pushes the sensing plate 22 against the force of the return spring 24. The sensor 23, upon detecting the movement of the sensing plate 22, confirms that the tubing has entered the housing 2 and sends a confirmation to the system.

At this time, the system responds to the confirmation signal sent by the detection mechanism to control an actuating mechanism such as a hydraulic oil cylinder 7 to drive a plurality of fixture blocks 6 of the clamping mechanism to move along respective guide blocks 9 to a working position matched with the pipe diameter of the specific oil pipe, and in the working position, the fixture blocks 6 abut against the rotating disc 13. It will be appreciated that depending on the pipe diameter specification, the rotary disc 13 will be rotated through different angles to bring the cartridge into position and bear against the end face of the rotary disc 13 or against a corresponding plurality of protrusions 14 on said end face.

Here, it should be noted that since the three dogs 6 act to retain the tubing body only in a general limit to the tubing, they do not limit the relative movement between the tubing and the closed elevator. In other words, the three clamping blocks present a 'virtual holding' state to the oil pipe body. Thus, as the hydraulic ram 7 drives the cartridge 6 down into contact with the tubing string in response to a control command from the system, the closed elevator 1 can move upwardly a small distance relative to the tubing 5 via the lifting lugs 3 until the collar portion 5b of the tubing can bear against the cartridge 6 (see figure 3), thereby allowing the tubing to move up and down with the closed elevator. At the same time, during the short distance of the closed elevator moving up relative to the tubing, the tubing will no longer be pressed against sensing plate 22, so that sensing plate 22 returns to the initial position due to the urging of return spring 24.

The elevator can realize 'one-crane-multiple-use' in the true sense by means of the automatic operation, and the automatic matching of the elevator and oil pipes with different specifications is realized by power, so that the complex operation of manually replacing the elevator is omitted, the operation efficiency is greatly improved, and the operation safety is improved.

It should be noted that the above-described embodiments should be regarded as merely illustrative, and the present invention is not limited to these embodiments. Various changes and modifications may be made by those skilled in the art without departing from the scope or spirit of the invention in view of the contents of this specification. With a true scope of the invention being indicated by the following claims and their equivalents.

Claims

1. A closed elevator comprises a shell and a clamping mechanism for clamping oil pipes, and is characterized in that the clamping mechanism comprises a plurality of clamping blocks which are arranged at intervals along the circumferential direction of the shell, the plurality of clamping blocks can be driven to a plurality of different working positions through an actuating mechanism, and the clamping blocks respectively clamp the oil pipes with different pipe diameters at the plurality of different working positions; the clamping mechanism further comprises a plurality of guide blocks which are arranged in the shell at intervals along the circumferential direction of the shell and provide motion guide for the plurality of clamping blocks, and each guide block is provided with an inclined guide surface for guiding the corresponding clamping block to move along the inclined direction on the inclined guide surface; each of the guide blocks includes a fixed portion having a first inclined guide surface, at least one slidable portion within the fixed portion having a second inclined guide surface that exceeds the first inclined guide surface in a radial direction in a natural position of the compression spring and is flush with the first inclined guide surface when the at least one slidable portion is fully embedded into the fixed portion against an elastic force of the compression spring, and a compression spring between the fixed portion and the at least one slidable portion.

2. The closed elevator as set forth in claim 1, further comprising a sensing mechanism for sensing and confirming entry of a tubing into the housing, the actuating mechanism actuating the plurality of dogs to an operating position matching a pipe diameter of the tubing in response to a confirmation signal from the sensing mechanism.

3. The closed elevator as set forth in claim 1, wherein the catching mechanism further comprises a rotary plate disposed below the guide block, one or more protrusion sets are provided at intervals in a circumferential direction on an end surface of the rotary plate opposite to the guide block, and each protrusion set includes the same number of protrusions as the number of the cartridges so that each protrusion can support a corresponding one of the cartridges.

4. The closed elevator as set forth in claim 3, further comprising a rotation cylinder driving a drive gear engaged with teeth provided on the outer circumference of the rotating disc to drive the rotating disc to rotate to different angles to allow the plurality of cartridges to abut against the end face of the rotating disc or against the corresponding plurality of protrusions on the end face.

5. The closed elevator as claimed in any one of claims 1 to 4, wherein the actuating mechanism comprises a plurality of hydraulic rams, each of the blocks being coupled to a vertically movable piston rod of a corresponding one of the hydraulic rams for lifting movement therewith.

6. The closed elevator as claimed in claim 5, further comprising a synchronizing ring moving together with the piston rod and the plurality of dogs, the synchronizing ring being circumferentially provided with a plurality of through grooves extending in a radial direction at intervals, each of the dogs comprising a detent received in a corresponding through groove of the synchronizing ring and axially retained in the through groove by a head of the detent; when the clamping blocks move up and down along with the piston rod, the clamping pins can move in the through grooves along the radial direction, so that the clamping blocks can move synchronously.

7. The closed elevator as set forth in claim 2, wherein the sensing mechanism comprises a sensing plate intended to be in contact with and pushed by tubing entering the housing, a sensor to determine that tubing has entered the interior of the housing based on movement of the sensing plate and to send a confirmation signal, and a return spring tending to return the sensing plate to an original position.

8. The closed elevator as recited in any one of claims 1 to 4 wherein the tubing comprises a tubing body having a first diameter and a collar portion having a second diameter, the second diameter being greater than the first diameter, the collar portion being intended to rest on the plurality of dogs.

9. The closed elevator according to claim 3 or 4, comprising a pilot member having a tapered opening coaxially disposed below the rotating pan, wherein tubing extends through the tapered opening and through a central opening of the rotating pan into the housing.

10. The closed elevator according to any one of claims 1 to 4, comprising a lifting lug for connection with a travelling block hook and a connecting rod for a soft guide rail for providing guidance in the lifting operation of the tubing.