CN212898384U - Single-stage ground anchor for well cementation - Google Patents

Abstract

The utility model relates to a single-stage ground anchor for well cementation, which comprises an outer body, a piston, a spring, a connecting rod and an anchor claw; the piston is sleeved in the outer body and fixedly connected with the inner wall of the outer body through a shear pin, the spring is sleeved on the outer wall of the piston, and two ends of the spring are limited by steps on the inner wall of the outer body and steps on the outer wall of the piston respectively; a plurality of groups of ground anchor mechanisms are uniformly distributed at the lower end of the piston in the circumferential direction, the spring is compressed by applying axial pressure to the piston, and the ground anchor mechanisms extend out through the side wall of the outer body, so that the anchoring of the ground anchor mechanisms is realized; when the axial pressure on the piston is removed, the spring drives the piston to return, and the ground anchor mechanism is reset. The single-stage ground anchor for well cementation of the utility model can open the fluke and bite into the stratum through the driving piston, and then the fluke is anchored with the stratum through lifting the pipe column; if the stratum is soft and the anchoring fails, the anchor fluke can be automatically retracted under the action of the spring resetting force, and then the pipe column is lifted to other positions to be anchored again.

Description

Single-stage ground anchor for well cementation

Technical Field

The utility model belongs to the technical field of the oil and gas cementing tool, especially, relate to a single-stage earth anchor for well cementation.

Background

At present, the technology commonly adopted by thick oil exploitation at home and abroad is a prestressed well cementation technology, particularly a casing ground anchor prestressed well cementation technology is taken as one of main technologies for preventing and treating casing damage of a thick oil thermal production well, and the technology has the characteristics of simple operation and convenient use. However, as the field application area continues to expand, the problem of exposure also increases. The earth anchor is used as a well cementation tool, when the earth anchor cannot be firmly anchored in a well wall, the fixing firmness of the casing in the well can be influenced, and once the casing cannot be firmly installed in the well, the well cementation quality can be reduced, the success rate of prestress well cementation is reduced, and therefore the risk of casing loss is increased. In addition, the single-stage fixed fluke adopted at present has no resetting function, and once the single-stage fixed fluke is opened, the single-stage fixed fluke cannot retract, so that the function of the fluke is failed due to unsuccessful anchoring. Therefore, the utility model designs a single-stage earth anchor with reset function.

Therefore, based on the problems, the single-stage ground anchor for well cementation, which has the reset function and improves the success rate of prestressed well cementation, has important practical significance.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to overcome prior art not enough, provide a single-stage earth anchor for well cementation with reset function, the success rate that improves the prestressing force well cementation.

The utility model provides a its technical problem take following technical scheme to realize:

a single-stage ground anchor for well cementation comprises an outer body, a piston and a spring; the piston is sleeved in the outer body and fixedly connected with the inner wall of the outer body through a shear pin, the spring is sleeved on the outer wall of the piston, and two ends of the spring are limited by steps on the inner wall of the outer body and steps on the outer wall of the piston respectively; a plurality of groups of ground anchor mechanisms are uniformly distributed at the lower end of the piston in the circumferential direction, the spring is compressed by applying axial pressure to the piston, and the ground anchor mechanisms extend out through the side wall of the outer body, so that the anchoring of the ground anchor mechanisms is realized; when the axial pressure on the piston is removed, the spring drives the piston to return, and the ground anchor mechanism is reset.

Furthermore, the ground anchor mechanism comprises a connecting rod and an anchor claw, wherein two ends of the connecting rod are respectively hinged with the bottom of the piston and the anchor claw, and the anchor claw is positioned in an anchor claw mounting groove in the side wall of the outer body and is hinged with the groove wall of the anchor claw mounting groove.

Furthermore, a plurality of first slots are formed in the lower end of the piston, second slots are formed in the anchor fluke, and two ends of the connecting rod are hinged to the slot walls of the first slots and the second slots respectively.

Further, the outer body and the piston are both of a hollow through structure, a clamp spring is mounted on the inner wall of the outer body, and the clamp spring can axially limit the piston.

Furthermore, the lower end of the outer body is fixedly connected with a guide shoe.

Furthermore, the guide shoe is a ball head guide shoe with a circulating hole.

The utility model has the advantages that:

the single-stage ground anchor for well cementation of the utility model can make the fluke open and bite into the stratum through the driving piston, then gradually increase the pull-up force after the fluke is anchored with the stratum by lifting the pipe column, make the well cementation pipe column generate certain prestress, and finally carry out the well cementation construction; if the stratum is soft and the anchoring fails, the anchor fluke can be automatically retracted under the action of the spring resetting force, and then the pipe column is lifted to other positions to be anchored again.

Drawings

The technical solution of the present invention will be described in further detail with reference to the accompanying drawings and examples, but it should be understood that these drawings are designed for illustrative purposes only and thus are not intended to limit the scope of the present invention. Furthermore, unless otherwise indicated, the drawings are intended to be illustrative of the structural configurations described herein and are not necessarily drawn to scale.

FIG. 1 is a sectional view of an initial state structure of a single-stage ground anchor for well cementation according to an embodiment of the present invention;

FIG. 2 is a structural cross-sectional view of the anchoring state of the single-stage ground anchor for well cementation according to the embodiment of the present invention;

FIG. 3 is a structural section view of the ground anchor mechanism of the single-stage ground anchor for well cementation according to the embodiment of the present invention;

Detailed Description

First, it should be noted that the specific structures, features, advantages, etc. of the present invention will be described in detail below by way of example, but all the descriptions are only for illustrative purpose and should not be construed as forming any limitation to the present invention. Furthermore, any single feature described or implicit in any embodiment or any single feature shown or implicit in any drawing may still be combined or subtracted between any of the features (or equivalents thereof) to obtain still further embodiments of the invention that may not be directly mentioned herein. In addition, for the sake of simplicity, the same or similar features may be indicated in only one place in the same drawing.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate the position or positional relationship based on the position or positional relationship shown in the drawings, or the position or positional relationship which is usually placed when the product of the present invention is used, and are only for convenience of description and simplification of the description, but do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," "third," and the like are used solely to distinguish one from another and are not to be construed as indicating or implying relative importance.

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict.

The present invention will be described in detail with reference to fig. 1 to 3.

As shown in fig. 1-3, the single-stage ground anchor for well cementation provided by the present embodiment includes an outer body 1, a piston 3, and a spring 4; the piston 3 is sleeved inside the outer body 1 and is fixedly connected with the inner wall of the outer body through a shear pin 5, the spring 4 is sleeved on the outer wall of the piston 3, and two ends of the spring are limited by a step on the inner wall of the outer body 1 and a step on the outer wall of the piston 3 respectively; a plurality of groups of ground anchor mechanisms are uniformly distributed at the lower end of the piston 3 in the circumferential direction, the spring 4 is compressed by applying axial pressure to the piston 3, and the ground anchor mechanisms extend out through the side wall of the outer body 1, so that the anchoring of the ground anchor mechanisms is realized; when the axial pressure on the piston 3 is removed, the spring 4 drives the piston 3 to return, and the ground anchor mechanism is reset.

Specifically, the ground anchor mechanism comprises a connecting rod 6 and an anchor claw 7, wherein two ends of the connecting rod 6 are respectively hinged with the bottom of the piston 3 and the anchor claw 7, and the anchor claw 7 is positioned in an anchor claw mounting groove 1-1 on the side wall of the outer body 1 and is hinged with the groove wall of the anchor claw mounting groove 1-1; the lower end of the piston 3 is provided with a plurality of first slots 6-3, the fluke 7 is provided with a second slot 7-2, the two ends of the connecting rod 6 are respectively hinged with the slot walls of the first slot 6-3 and the second slot 7-2, and it should be noted that when the fluke 7 is not anchored, the fluke is positioned in the fluke mounting groove 1-1, and the single-stage ground anchoring is not hindered.

The outer body 1 and the piston 3 are both of a hollow through structure, a clamp spring 2 is installed on the inner wall of the outer body 1, and the clamp spring 2 can axially limit the piston 3.

The upper end of the outer body 1 is connected with a well cementation casing string, the lower end of the outer body is connected with a guide shoe 8 through threads, and the guide shoe 8 is a ball head guide shoe with a circulation hole.

The outer body 1, the piston 3, the spring 4, the guide shoe 8 and the fluke 7 are coaxial.

In the embodiment, the piston 3 is a boss-shaped hollow structure and can axially move under the action of axial force, and the clamp spring 2 limits the upward movement limit position of the piston 3; the ground anchor mechanism of the embodiment is composed of three groups, the upper end of a connecting rod 6 is arranged in a slotted groove 6-3 designed at the lower end of a piston 3 in a circumferentially and uniformly distributed mode and is hinged together through an upper connecting rod pin 6-1, the lower end of the connecting rod 6 is matched with a slotted groove 7-2 of an anchor claw 7 and is hinged together through a lower connecting rod pin 6-2, the connecting rod 6 can rotate for a certain angle around the upper connecting rod pin 6-1 and the lower connecting rod pin 6-2, the anchor claw 7 is arranged in an anchor claw mounting groove 1-1 at the lower end of an outer body 1 and is hinged together with the body 1 through an anchor claw pin 7-1, and the anchor claw 7 can rotate for 90 degrees around the anchor claw pin. When the anchor fluke 7 works, a certain axial downward force needs to be provided for the piston 3, the piston 3 shears the shear pin 5 under the axial downward force to compress the spring 4 to move downwards, the connecting rod 6 is further pushed to rotate around the connecting rod upper pin 6-1 and the connecting rod lower pin 6-2, so that the anchor fluke 7 is pushed to rotate around the anchor fluke pin 7-1 and expand outwards, and the anchor fluke 7 is further sunk into the stratum and anchored by lifting the sleeve string. And as the ground anchor is anchored, the casing string can be prestressed by continuously lifting the casing string. If anchor fluke 7 fails to anchor for the first time, the downward pressure of piston 3 can be released, piston 3 can reset anchor fluke 7 under the action of the reset force of spring 4, and the position can be adjusted to implement anchoring operation again.

The above embodiments are described in detail, but the above description is only for the preferred embodiments of the present invention, and should not be construed as limiting the scope of the present invention. All the equivalent changes and improvements made according to the application scope of the present invention should still fall within the patent coverage of the present invention.

Claims (6)

1. A single-stage ground anchor for well cementation is characterized in that: comprises an outer body (1), a piston (3) and a spring (4); the piston (3) is sleeved inside the outer body (1) and is fixedly connected with the inner wall of the outer body through a shear pin (5), the spring (4) is sleeved on the outer wall of the piston (3), and two ends of the spring are limited by a step on the inner wall of the outer body (1) and a step on the outer wall of the piston (3) respectively; a plurality of groups of ground anchor mechanisms are uniformly distributed at the lower end of the piston (3) in the circumferential direction, the spring (4) is compressed by applying axial pressure to the piston (3), and the ground anchor mechanisms extend out of the side wall of the outer body (1) to realize anchoring of the ground anchor mechanisms; when the axial pressure on the piston (3) is removed, the spring (4) drives the piston (3) to return, and the ground anchor mechanism is reset.

2. A single-stage earth anchor for cementing according to claim 1 wherein: the ground anchor mechanism comprises a connecting rod (6) and a fluke (7), wherein two ends of the connecting rod (6) are respectively hinged with the bottom of the piston (3) and the fluke (7), and the fluke (7) is positioned in a fluke mounting groove (1-1) on the side wall of the outer body (1) and is hinged with the wall of the fluke mounting groove (1-1).

3. A single-stage earth anchor for well cementation according to claim 2, wherein: the lower end of the piston (3) is provided with a plurality of first slots (6-3), the fluke (7) is provided with a second slot (7-2), and two ends of the connecting rod (6) are respectively hinged with the slot walls of the first slot (6-3) and the second slot (7-2).

4. A single-stage earth anchor for cementing according to claim 1 wherein: the outer body (1) and the piston (3) are both of a hollow through structure, a clamp spring (2) is installed on the inner wall of the outer body (1), and the clamp spring (2) can axially limit the piston (3).

5. A single-stage earth anchor for cementing according to claim 1 wherein: the lower end of the outer body (1) is fixedly connected with a guide shoe (8).

6. A single stage earth anchor for cementing according to claim 5 wherein: the guide shoe (8) is a ball head guide shoe with a circulating hole.

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