CN108468522B - Grind shoe - Google Patents

Abstract

The application provides a junk mill, this junk mill is used for boring and grinds the bridge plug that sets up in the sleeve pipe, includes: the shoe grinding head is externally provided with a slip capable of rotating relatively, and the outer wall and the inner wall of the slip are respectively provided with an outer clamping tooth and an inner clamping tooth; the slips are insertable between the bridge plug and the casing such that the inner and outer dogs are anchored to the outer wall of the bridge plug and the inner wall of the casing respectively. The grinding machine provided by the embodiment of the invention can fix the bridge plug to be unsealed, and the rotation of the bridge plug is avoided, so that the drilling and grinding efficiency of the bridge plug is improved.

Description

Grind shoe

Technical Field

The application relates to the technical field of underground workover equipment, in particular to a mill shoe.

Background

The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.

In the process of oil testing operation, the bridge plug plugging operation is often required to be carried out on the tested layer position. When the well needs to be re-worked, the bridge plug needs to be unsealed.

Typically, the bridge plug is not fixed in the casing. Therefore, the bridge plug can rotate along with the rotation of the grinding shoe, so that the grinding shoe has low drilling and grinding efficiency on the bridge plug. Even when the bridge plug and the grinding shoe rotate synchronously, the grinding shoe cannot drill and grind the bridge plug, and the bridge plug is not unsealed.

It should be noted that the above background description is only for the convenience of clear and complete description of the technical solutions of the present application and for the understanding of those skilled in the art. Such solutions are not considered to be known to the person skilled in the art merely because they have been set forth in the background section of the present application.

Disclosure of Invention

Based on the foregoing defects in the prior art, embodiments of the present invention provide a milling shoe, which can fix a bridge plug to be unsealed, and prevent the bridge plug from rotating, thereby improving the drilling and milling efficiency of the bridge plug.

In order to achieve the above object, the present application provides the following technical solutions.

A milling shoe for drill milling a bridge plug disposed in a casing, comprising: the shoe grinding head is externally provided with a slip capable of rotating circumferentially relative to the shoe grinding head, and the outer wall and the inner wall of the slip are respectively provided with an outer clamping tooth and an inner clamping tooth; the slips are insertable between the bridge plug and the casing such that the inner and outer dogs are anchored to the outer wall of the bridge plug and the inner wall of the casing, respectively.

According to the embodiment of the invention, the shoe grinding head is externally provided with the slip capable of rotating circumferentially relative to the shoe grinding head, and the inner wall and the outer wall of the slip are respectively provided with the inner clamping teeth and the outer clamping teeth. So, when the slips inserted between bridging plug and the sleeve pipe, interior calorie of tooth and outer calorie of tooth anchor respectively in the outer wall of bridging plug and the sheathed tube inner wall to can fix the bridging plug, restrain the bridging plug and grind the first emergence rotation together of shoes, the brill of bridging plug grinds efficiency and can improve.

Further areas of applicability will become apparent from the description provided herein. The description and specific examples of this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.

Drawings

The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way. In addition, the shapes, the proportional sizes, and the like of the respective members in the drawings are merely schematic for assisting the understanding of the present application, and are not particularly limited to the shapes, the proportional sizes, and the like of the respective members in the present application. Those skilled in the art, having the benefit of the teachings of this application, may select various possible shapes and proportional sizes to implement the present application, depending on the particular situation. In the drawings:

fig. 1 is a perspective view of a grind shoe according to an embodiment of the present invention;

fig. 2 is a cross-sectional structural view of a grind shoe according to an embodiment of the present invention;

FIG. 3 is a schematic view of an assembly structure of an upper joint and a grinding shoe head in the grinding shoe according to the embodiment of the invention;

FIG. 4 is a schematic structural view of the centering sleeve of FIG. 1;

FIG. 5 is a schematic diagram of the slip of FIG. 1.

Detailed Description

It will be understood that when an element is referred to as being "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. As used herein, the terms "vertical," "horizontal," "left," "right," and similar expressions are for the purpose of illustration based on the drawings in the specification and are not meant to be the only embodiments.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the description of the present application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

As shown in fig. 1-5, embodiments of the present invention provide a milling shoe that may be used to drill and mill a bridge plug disposed in a casing.

It may include: the shoe grinding machine comprises a shoe grinding head 1, wherein aslip 2 capable of rotating circumferentially relative to the shoe grinding head 1 can be arranged outside the shoe grinding head 1, and aninner clamping tooth 201 and anouter clamping tooth 202 can be respectively arranged on the inner wall and the outer wall of theslip 2; theslips 2 can be inserted between a bridge plug and a casing so that the inner andouter dogs 201 and 202 can be anchored to the outer wall of the bridge plug and the inner wall of the casing respectively.

According to the embodiment of the invention, the outer part of the shoe grinding head 1 is provided with theslip 2 which can rotate relative to the shoe grinding head in the circumferential direction, and theinner clamping teeth 201 and theouter clamping teeth 202 are respectively arranged on the inner wall and the outer wall of theslip 2. Thus, when theslip 2 is inserted between the bridge plug and the sleeve, theinner clamping teeth 201 and theouter clamping teeth 202 are anchored on the outer wall of the bridge plug and the inner wall of the sleeve respectively, so that the bridge plug can be fixed, the rotation of the bridge plug and the grinding head 1 is inhibited, and the drilling and grinding efficiency of the bridge plug is improved.

In general, if only one bridge plug is arranged, a grinding shoe drill is used for grinding the bridge plug, after a protective umbrella at the upper part of the bridge plug is damaged, the bridge plug loses support, the bridge plug is communicated to the bottom of a well, and the bridge plug is unsealed.

If there are multiple bridge packings, the resulting bridge packing residue will fall over the next bridge packing after the upper bridge packing has been destroyed. Then, when the next bridge plug is unsealed, the residue of the previous bridge plug needs to be crushed and recycled out of the well bore, otherwise the drilling and grinding efficiency of the next bridge plug is affected.

If the grinding shoe in the prior art is used for drilling and grinding the next bridge plug, the residual body scattered on the next bridge plug can also rotate under the driving of the grinding shoe. The purpose of breaking the remains is then not efficient or even achievable.

By adopting the grinding shoe provided by the embodiment of the invention, as the bridge plug is fixed, the residual body scattered on the bridge plug can be better crushed, and the high-efficiency drilling and grinding of the residual body and the bridge plug are realized.

In other words, the milling shoe of the embodiment of the invention is not only suitable for drilling and milling and unsealing scenes of a single bridge plug, but also has better implementation effect on scenes with a plurality of bridge plugs.

In this embodiment, the milling head 1 may be substantially hollow cylindrical, and its end portion may be provided with anotch 101, and the hardness of the end portion is large to cut and grind the bridge plug and the remnants.

In the present embodiment, since the circumferential rotation of the bridge plug is to be suppressed, the inner andouter teeth 201, 202 preferably extend in the up-down direction, i.e., the axial direction, and may be formed in a specific manner as teeth. Thus, the inner andouter clamping teeth 201, 202 are perpendicular to the circumferential direction, and the bridge plug can be fixed better.

Of course, the inner andouter teeth 201, 202 may be formed in a manner not limited to the above-described embodiment. For example, it is also possible to have the inner and outer walls of theslip 2 have uneven surfaces to form the inner andouter gripping teeth 201, 202.

In addition, the inner wall surface of theslip 2 may be inclined upward so that the lower end of theslip 2 forms a tapered guide head, so that the lower end of theslip 2 is spaced apart from the grinder head 1. In this manner, theslips 2 may be easily inserted between the bridge plug and the casing.

And, the preferred quantity ofslips 2 is a plurality of, and a plurality ofslips 2 evenly arrange outside mill shoe head 1 along circumference to reach even high efficiency and bore the purpose of grinding.

In one embodiment, the outer surface of the milling head 1 can be sleeved with arotatable centering sleeve 3, the outer wall of the centeringsleeve 3 is expanded outwards to form ahoop part 301, a limited space (not shown) is formed between thehoop part 301 and the outer wall of the milling head 1, and theslips 2 are inserted in the limited space, thereby realizing circumferential rotation of theslips 2 outside the milling head 1.

In this embodiment, thecentering sleeve 3 may be substantially cylindrical and is concentrically disposed with the milling shoe head 1 and a lower joint described below, so as to center a pipe string on which the milling shoe of the embodiment of the present invention is mounted, and to prevent the pipe string from swinging during drilling and milling.

The main centering function of thecentering sleeve 3 is thehoop 301, and afirst stop step 302 described below. The principle is that hoopingportion 301 andfirst backstop step 302 are a plurality of and correspond the setting, and a plurality of hoopingportions 301 andfirst backstop step 302 are evenly arranged outside rightingcover 3 along circumference, and the outer wall of a plurality of hoopingportions 301 andfirst backstop step 302 is the arc with sleeve pipe looks adaptation to, a plurality of hoopingportions 301 andfirst backstop step 302 can hug closely the sleeve pipe inner wall, thereby realize righting the function.

Further, the first stoppingstep 302 is formed by protruding the outer wall of thecentering sleeve 3 corresponding to theanchor ear 301, and the upper end of theslip 2 can be fixed on the first stoppingstep 302, so as to limit and fix theslip 2.

In order to limit and axially fix the centeringsleeve 3, in one embodiment, the upper end of the grinding shoe head 1 may be connected with an upper joint 4, thecentering sleeve 3 may be sleeved outside the upper joint 4 and can rotate, an outer wall of the upper joint 4 near the upper end may protrude outward to form a second stoppingstep 401, an outer wall of the grinding shoe head 1 near the lower end may protrude outward to form a third stoppingstep 102, and the centeringsleeve 3 is limited between the second stoppingstep 401 and the third stoppingstep 102.

In this embodiment, the upper joint 4 may be threadedly provided at the upper end of the grinder shoe head 1. Thus, therighting sleeve 3 inserted with theslips 2 in theanchor ear 301 can be sleeved on the shoe grinding head 1 first, and the third stoppingstep 102 is fixed at the lower end of the rightingsleeve 3. Subsequently, the upper adapter 4 can be inserted into the centeringsleeve 3 and connected with the milling head 1 by means of a thread until thesecond stop step 401 abuts against the upper end of the centeringsleeve 3. By now the centeringsleeve 3 is confined between thesecond stop step 401 and thethird stop step 102, the assembly of the milling shoe of the embodiment of the invention is completed.

Also, in order to limit and axially fix theslip 2, in one embodiment, an outer wall of theslip 2 near the lower end may be outwardly protruded to form a first limiting portion, and an upper surface of the first limiting portion may abut against a lower surface of thehoop portion 301. Further, the outer wall of theslip 2 near the upper end may protrude outward to form a second limitingportion 205, and the lower surface of the second limitingportion 205 may be hung on the upper surface of thehoop portion 301.

In this way, a necked-downportion 206 may be formed between the first stopper portion and thesecond stopper portion 205, and the necked-downportion 206 may be caught in thehoop portion 301. Therefore, the upper surface and the lower surface of thehoop part 301 respectively support the upper surface of the second limitingpart 205 and the lower surface of the first limiting part, and limiting and axial fixing of theslip 2 are achieved.

In addition, the side wall of thehoop part 301 can fix the side wall of thenecking part 206, so as to form an anti-rotation effect on theslip 2.

The mill shoe provided by the embodiment of the invention is suitable for a vertical well or a horizontal well, and the using method comprises the following steps:

the first step is as follows: connecting the mill shoe to the lower end of the pipe column and putting the mill shoe into the well;

the second step is that: after the grinding shoe contacts the bridge plug, lowering the pipe column and keeping a certain bit pressure;

the third step: rotating the pipe column, and starting to drill and grind the shaft bottom bridge plug;

the fourth step: after drilling and grinding for a certain length, continuously lowering the pipe column, keeping a certain drilling pressure, and continuously drilling and grinding until the drilling and grinding of the bridge plug in the well is finished;

the fifth step: and after drilling and grinding are finished, pulling out the pipe column.

The grinding shoe of the embodiment of the invention improves the success rate of one-time construction, is convenient to operate, reduces the labor intensity of workers, shortens the construction operation period, saves the construction cost and reduces the operation workload.

It should be noted that, in the description of the present application, the terms "first", "second", and the like are used for descriptive purposes only and for distinguishing similar objects, and no precedence between the two is intended or should be construed to indicate or imply relative importance. In addition, in the description of the present application, "a plurality" means two or more unless otherwise specified.

The above description is only a few embodiments of the present invention, and those skilled in the art can make various changes or modifications to the embodiments of the present invention based on the disclosure of the invention document without departing from the spirit and scope of the present invention.

Claims (8)

1. A milling shoe for drill milling a bridge plug disposed in a casing, comprising: the shoe grinding head is externally provided with a slip capable of rotating circumferentially relative to the shoe grinding head, and the outer wall and the inner wall of the slip are respectively provided with an outer clamping tooth and an inner clamping tooth; the slips can be inserted between the bridge plug and the casing to enable the inner clamping teeth and the outer clamping teeth to be anchored on the outer wall of the bridge plug and the inner wall of the casing respectively; a plurality of teeth extending along the up-down direction are arranged on the inner wall of the slip to form the inner clamping teeth; the outer wall of the slip is provided with a plurality of teeth extending along the up-down direction to form the outer clamping teeth.

2. The milling shoe as set forth in claim 1, wherein the inner walls of the slips are arranged to be inclined upward such that the lower ends of the slips form a guide head having a tapered shape, whereby the lower ends of the slips are spaced apart from the milling head.

3. The milling shoe as claimed in claim 1, wherein the milling head is externally provided with a rotatable centering sleeve, the outer wall of the centering sleeve is expanded outward to form a hoop part, a limited space is formed between the hoop part and the outer wall of the milling head, and the slip is inserted into the limited space.

4. The shoe mill of claim 3, wherein the outer wall of the slip near the lower end is outwardly convex to form a first stopper, and an upper surface of the first stopper abuts against a lower surface of the hoop section.

5. The shoe mill of claim 4, wherein the outer wall of the slip near the upper end is outwardly convex to form a second limiting portion, and the lower surface of the second limiting portion is hung on the upper surface of the hoop portion.

6. The milling shoe as set forth in claim 5, wherein a necked-down portion is formed between the first and second stoppers, the necked-down portion being caught in the anchor ear portion.

7. The shoe mill of claim 3, wherein the centering sleeve is outwardly protruded corresponding to an outer wall of the band portion to form a first stopping step, and an upper end of the slip abuts against the first stopping step.

8. The milling shoe as claimed in claim 3, wherein an upper joint is connected to the upper end of the milling head, the centering sleeve is rotatably provided outside the upper joint, the outer wall of the upper joint adjacent to the upper end is outwardly protruded to form a second stopping step, the outer wall of the milling head adjacent to the lower end is outwardly protruded to form a third stopping step, and the centering sleeve is retained between the second stopping step and the third stopping step.

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