US3785690A - Tool for use in removing a fish stuck within a well bore - Google Patents

Abstract

There is disclosed a tool in which a tubular body having a means on its lower end for connection to a fish stuck within the bore is adapted to be connected to a running string for suspension in a well bore, and a washpipe having a cutting surface on its lower end is supported by the tubular body for raising and lowering therewith.

Description

[451 Jan. 15, 1974 TOOL FOR USE IN REMOVING A FISH STUCK WITHIN A WELL BORE [75] Inventor: Carl P. Hutchinson, Houma, La. Primary Examiner-Evon C. Blunk Assistant Examiner-James L. Rowland Assignee. $6115 Industries, Inc., Houston, Atmmey w. F. y et a].

[22] Filed: May 5, 1972 [21] App]. No.: 250,593

ABSTRACT There is disclosed a tool in which a tubular body hav- [52] US. 294/8634, 166/99 ing a means on its lower end for connection to a fish [51] Int. E2lb 31/02 Stuck within the bore is adapted to be connected to a [58] Field of Search...................... 294/8634, 86.12, running String for suspension in a we" bore, and a washpipe having a cutting surface on its lower end is supported by the tubular body for raising and lowering therewith.

[56] References Cited UNITED STATES PATENTS 2,762,438 9/1956 Naylor................. 294/8634 6 Claims, 6 Drawing Figures hmbwhmiauflllllliil Iii/[Iflllltiilllllr PATENTEB JAN 1 5 I974 SHEET 2 0F 2 TOOL FOR USE IN REMOVING A FISH STUCK WITHIN A WELL BORE This inventionrelates generally to a tool for usein removing a fish stuck within a well bore. More particularly, it relates to improvements in tools of this type which include a washover pipe having an annular cut ting surface at its lower end for use in removing obstructions about the fish, and a tubular body arranged concentricallyof the'washpipe and having means at its lower end for connecting with the fish when the obstructions are removed to permit it to be raised from the well bore.

In tools of this latter type, the washover pipe and the tubular body are lowered into and raised from the well bore by means of arunning string, which maybe a drill pipe extending to the ground level. With the ltoollowered to a position in which the cutting surface is engaged with the obstruction about the fish, the running string is rotated togrind against the obstruction and liquid is circulated down through the string and tool and up through the annulus about them to remove the cuttings/When enough of the fish is cleared, the string is manipulated to cause the connecting means, which may be an overshot or the like, to connect with the fish, and thereby permit the fish to be lifted with the tool from the well bore.

In typical tools of this type, such as those shown in Naylor US. Pat. No. 2,762,438 andLe Bus et al., US. Pat. No. 3,070,170, the washover pipeis connected directly to the lower end of the drill stringand the tubular body is suspended within the washpipe with the fish connecting means above the cutting surface. After connection of the connecting meansto the fish, the running string is manipulated to release the tubular body from the washpipe and cause it to assume a position in which it will be caught and suspended by the washpipe automatically in response to release of the fish. At this time, the washpipe may again be rotated so as to drill out more of the obstruction until the fish is released.

The tubular goods from which washpipes are made are relatively thin and thus incapable of withstanding high stresses and strains. Consequently, in the tools of the aforementioned prior patents, wherein the washpipes are connected directly to the running string, its impossible to perform certain fishing operations, such as heavy jarring, which maybe required to release the fish, at least without removal of the tool. It may also be difficult, if not impossible, to perform other fishing operations which require reverse (left-hand) rotation of the running string, such as in manipulating string shots or in connecting certain overshots and spears, or which require considerable torque, suchas in operating internal and external cutters. Furthermore, the manipulation of these tools in order to prepare the tubular body for being caught by the washpipe is dependent on a number of parts such as slips, clutches and the like, which are expensive as well as susceptible to malfunction. Also, the washpipe must transmit torque in a lefthand direction, which is undesirable in the manipulation of any downhole running string made up with right-hand torque.

An object of this invention is to provide a tool of this type in which, despite the. inherent weakness of the washpipe, such fishing operations may be performed without removing the tool.

Another object is to provide such a tool whose operation is not dependent on such parts, and thus which is of inexpensive construction and operable in a troublefree manner.

These and other objects are-accomplished, in accordance with the illustrated embodiment of the .present invention, by a .tool'in which, as distinguished from the above-described *tools, the tubular body is adapted for connection directly to the running string, and the washover pipe is carried thereabout for lowering and!raising into and out of a position in which ithe'cutting surface is engaged with 'the obstruction about the fish. More particularly,the body and washpipeare provided with mans responsive 'to manipulation of the running string for supporting the washpipe from the body, whereby 'it may be so raised and lowered, for rotating the ,pipe with the body,-so.as-to=cause saidcutting surface'to remove a'portion 'ofitheobstruction when so engagedtherewith, and for imposing a downward loadon the body to "the pipeas it is so rotated. The running string is also manipulatable to selectively disengage such means and therebyrelease the-bodyformovement vertically and -for rotation free of the washpipe; and, since the body is of relatively heavy tubular stock similar to 'the running -string,the lattermay'be further manipulated to not only cause therneans on the lower end of the body to be connected to the fish, but also, upon such connection,'to perform various operations, such as jarring, in orderto release the fish.

More particularly, the means forsupporting, rotating and imposing a.downward load on the washpipe comprises a slot in the body having shoulders engagable with a lug on the washpipe so as to move the washpipe vertically as well as rotationally in response to manipulation of the running tool. The slot opens'to a portion of the body in which the lug is freely received so that, upon manipulationof the running tool to dispose the lug opposite this portion, the tool and thus the connecting means on itslower end are released for movement vertically as well as rotationally with respect to the washpipe.

Thus, the connecting meansmay comprise any well known part, such as a tool joint, a spear, an overshot or the like, adapted'to be made up in response to vertical reciprocation, the transmission of torque, or a combination of same. Also, the running string may be manipulatedtoperform various fishing operations, such as heavy jars, requiring the transmission of high stresses and strains to the body.'Moreover, all such operations are performed without parts such as slips and clutches between the washpipe and body. Upon release of the fish, the running too] may be manipulated to cause the slot to receive the lug for engagement with a shoulder on the slot, so as to support the washpipe from the tubular body and permit the entire tool to be removed with the fish from the well bore.

In the drawings, wherein like reference characters are used throughout to designate like parts:

FIG. 1 is a longitudinal sectional view of the tool as it is being lowered within a well bore in which a fish is stuck;

FIG. 2 is a view similar to FIG. 1, but wherein the cutting surface about the lower end of the washpipe has drilled out a portion of an obstruction about the fish;

FIG. 3 is another view similar to FIGS. 1 and 2, but in which an overshot at the lower end of the tubular body has been connected to the fish;

FIG. 4 is an enlarged longitudinal sectional view of a portion of the tool, showing the lug on the washpipe in the position it occupies within a slot in the tubular body as the body is being released from the washpipe;

FIG. 5 is a development of the slot in the tubular body, showing the lug in broken lines in the positions it occupies during each of the operations illustrated in FIGS. 1, 2 and 4; and

FIG. 6 is a cross-sectional view of the tool, as seen along broken lines 6-6 of FIG. 4.

With reference now to the details of the abovedescribed drawings, the tool, which is indicated in its entirety by reference character 10, is shown within a well bore 11 lined with casing. The tool is somewhat smaller than the well bore 11 to provide an annulus through which fluid may be returned during washover. A fish, which may be one or more joints of tubing 12, is stuck within the well bore a considerable distance below ground level. The cause of its being stuck may stem from one or more of several circumstances, and, in any event, soil or debris has accumulated on or about the fish to obstruct access thereto, so that a washover operation is required. In the particular instance illustrated in the drawings, soil has accumulated in the annulus 13 above a packer 14 about the tubing so as to obstruct a coupling 14A at the upper end of the tubing to which an overshot is to be connected.

As shown in the drawings, the tool includes a tubular body 15 adapted to be suspended within the well bore by means of a running string (not shown) connected to its upper end, and a washpipe 16 surroundingthe tubular body and adapted to be supported thereby for movement vertically within the well bore. There is a cutting surface 17 on the lower end of the washpipe, and a fish connecting means 18 on the lower end of the tubular body. With the washpipe supported by the tubular body, as shown in FIG. 1, the connecting means 18 is a maximum distance above the cutting surface 17. The connecting means 18 is a standard overshot, which is especially useful for connecting with a coupling 14A, although in other obvious uses of the tool, the connecting means may instead be of any other conventional construction, such as a tool joint, a spear or the like.

The washpipe 16 has an inner diameter 16A adapted to fit over the coupling 14A, as shown in each of FIGS. 2 and 3, and closely about the relatively enlarged lower portion 15A of the tubular body 15. The upper end of the washpipe is reduced at 165 so as to fit closely about a reduced upper portion 158 of the tubular body and carries seal rings 19 to form a sliding seal therewith during reciprocation and rotation of the body with respect to the washpipe. When the washpipe is supported from the body, as shown in FIG. '1, an upwardly facing annular shoulder 20 on the tubular body at the intersection of its portions 15A and 15B is spaced just beneath a downwardly facing shoulder 21 on the washpipe at the intersectionof its reduced upper end 168 with its inner diameter 16A.

A slot 22 is formed on opposite sides of the upper end of the lower portion 15A of the tubular body, and a pair of lugs 23 are provided on opposite sides of the inner diameter of the washpipe 16, each lug being of a size for fitting closely within one of the slots. More particularly, each slot extends downwardly from the shoulder 20 about the tubular body so that the lug adapted to fit therein may be moved between various positions within the slot when the tubular body is in a raised position relative to the washpipe, as shown in FIGS. 1 and 2, and positions removed from the slot and opposite reduced body portion 158 above the shoulder 20, when the tubular body is in a lowered position with respect to the washpipe, such as shown in FIG. 3. As will be described to follow, when a lug is within its slot, it si cooperable with shoulders formed by the slot so as to manipulate the washpipe in a desired manner in response to rotation and reciprocation of the running string and thus the tubular body suspended therefrom. On the other hand, when a lug is removed from its slot, the tubular body is free to be reciprocated and rotated responsive to manipulation of the running string, but without influencing the washpipe so that it may be connected to the fish and operated to perform on the fish without imparting heavy stresses and strains to the washpipe.

As best shown in its development in FIG. 5, the slot 22 includes a first generally vertical portion 220 extending downwardly from the shoulder 20 about the tubular body, a generally horizontal portion 22b extending laterally from the lower end of the portion 220, and second and third generally vertical portions 22c and 22d extending respectively upwardly and downwardly from the end of the portion 22b. As shown, the lug is somewhat elongated, and the vertical portions 22a, 22c and 22d of the slot are therefore rather narrow for fitting closely against the sides of the lug, while the portion 22]; thereof is relatively wide for fitting closely against the upper and lower ends of the lug.

When the lug is within the slot 22, and a strain or upward pull is taken on the running string, and thus the tubular body, the upwardly facing shoulder provided by the lower end of the slot portion 22d will move upwardly into engagement with the lower end of the lug to support the washpipe, as shown in FIG. 1. On the other hand, when the washpipe is landed, as when it has been lowered onto the obstruction about the fish, the weight of the running string, and thus the tubular body, may be slacked off so as to permit the slot 22 to move downwardly until the downwardly facing shoulder on the upper end of the slot portion 22c engages the upper end of the lug 23. In either of these positions, the running string and thus the tubular body may be rotated in a right-hand direction so as to cause the shoulder provided by the side of the slot portion 22c or 22d to bear against the side of the lug and thereby rotate the washpipe with the body.

In order to remove the lug from the slot, the running string is moved vertically so as to dispose the end of the slot portion 22b opposite the lug 23, and then rotated in a right-hand direction to cause such portion of the slot to move laterally over the lug, as shown in each of FIGS. 4 and 5. When the side of the lug engages the shoulder provided by the side of slot portion 22a, the weight of the running string may be slacked off to permit such slot portion to move downwardly over the lug, so as to cause the lug to be removed from the slot and opposite portion 158 of the body. The extent to which the slot 22, and, thus the connecting means 18 on the lower end of the tubular body, moves downwardly depends, of course, on the extent to which the running string is slacked off.

As shown, the horizontal portion 22b of the slot preferably slants downwardly in a direction away from the first vertical portion 22a. As will be understood, this will facilitate movement of the lug between the positions of FIGS. 1 or 2 and a position removed from the slot. Also, the upper end of the first vertical portion 22a of the slot is flared upwardly at 24 so as to facilitate movement of such portion upwardly with respect to the lower end of the lug as the body is being manipulated to cause the slot to receive the lug.

As shown, the washpipe 16 comprises one or more joints of relatively thin wall pipe 25 and a sub 26 connected to the upper end thereof. The seal means 19 carried by the sub 26 may be of any suitable construction, such as that shown in FIG. 4, for sealing about body portion B against pressure differential in either direction. The tubular body 15 is made up of several threadedly connected joints of relatively heavy wall pipe, preferably of the same strength as the drill pipe of which the running string is ordinarily composed. As previously described, the overshot 18 on the lower end of the body may be replaced by any other suitable fish connecting means.

When the lug 23 is received by the slot 22, and a strain is taken on the running string, the lug will naturally assume the position shown in FIG. 1, so as to support the washpipe from the tubular body. When the tool is then lowered within the well bore to cause the cutting surface 17 on the lower end of the washpipe to engage the obstruction 13 about the fish, the overshot 18 will of course be a very substantial distance above the fish. The running string and thus the tubular body may then be rotated to the right so as to transmit torque to the lug 23 and thus rotate the washpipe and its cutting surface to drill out the obstruction, and water may be circulated down through the string'and tool and up through the annulus so as to remove the cuttings.

In order to urge the cutting surface against the soil 13 with considerable downward force, atleast some of the weight of the running string may be slacked off to cause the slot 22 to move downwardly with respect to the lug 23 and thus cause the lug to move into the vertical portion 220 of the slot, as shown in FIG. 2. In this manner, a desired amount of the weight of the drill string may be transmitted from the upper end of such slot portion to the top of the lug 23 and thus to the cutting surface 17 at the lower end of the washpipe. Even when the tubular body is lowered for this purpose, the overshot 18 is still a substantial distance above the fish, so that rotation of the washpipe may be continued so as to drill out the obstruction 13 to the depth indicated in FIG. 2, at which time the coupling 14A is exposed sufficiently to permit the overshot 18 to be connected thereto.

At this time, a strain is again taken on the running string so as to cause the tubular body and thus the slot 22 to be moved upwardly with respect to the washpipe so that the lug is brought into engagement with the bottom of slot portion 22d. The running string is then manipulated to apply right-hand torque and gradually slacked off to cause the tubular body and thus the slot to gradually move downwardly with respect to the lug 23 until the lug is opposite the horizontal slot portion 22b, and then to rotate to the right with respect to the lug so that the lug moves through such portion 22b and into the lower end of the vertical portion 22a. At this time, the torque may be relieved and the slackening off continued to permit the slot portion 22a to move downwardly past such portion, whereby the lug is caused to assume a position opposite reduced portion 158 of the tubular body, whereby the tubular body is free for reciprocation and rotation with respect thereto.

In some cases, it may be desirable for the vertical slot portions 220 and 22d to be on the opposite side of slot portion 22a, and thus for the portion 22b to extend laterally from portion 22a in a counterclockwise direction. With such an arrangement, the lug could not be freed from and/or reengaged with the slot by right-hand rotation of the body, but, instead, left-hand rotation would be required for this purpose. In any event, this alternative arrangement is contemplated by the present invention.

This freedom of movement of the tubular body with respect to the washpipe permits the tubular body to be lowered until the overshot 18 moves over the upper exposed end of the fish, and then further lowered and/or rotated by suitable manipulation of the running string so as to connect the overshot with the fish. Upon such connection, jarring, back-off, or other operations which place high stresses or strains on the running string, and thus the tubular body, may be performed to release the body from its stuck position.

When this has been accomplished, a strain may be taken on the running string so as to lift the shoulder 20 about the tubular body into engagement with the lower ends of the lugs 23 on the inner diameter of the washpipe, and the running string may be rotated so as to cause the flared upper end 24 of the slot portions 22a to receive the lugs 23. In a manner obvious from the foregoing description, continued strain on the running string will cause the slot to continue to move upwardly until the lug 23 is received in the lower end of slot portion 22d, at which time the washpipe is again supported by the tubular body, and the running string may be raised so as to lift the tool together with the fish from the well bore.

From the foregoing it will be seen that this invention is one well adapted to attain all of the ends and objects hereinabove set forth, together with other advantages which are obvious and which are inherent to the apparatus.

It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations. This is comtemplated by and is within the scope of the claims.

As many possible embodiments may be made of the invention without departing from the scope thereof, it is to be understood that all matter herein set forth or shown in the accompanying drawings is. to be interpreted as illustrative and not in a limiting sense.

The invention having been described, what is claimed l. A tool for use in releasing a fish stuck within a well bore, comprising a tubular body adapted to be connected to the lower end of a running string for suspension within the well bore, a washover pipe surrounding the body, an annular cutting surface on the lower end of the pipe adapted to surround the fish, means on the lower end of the body for connecting with the fish so as to lift it from the well bore, and means responsive to manipulation of the running string for supporting the pipe from the bodyi'to permit the pipe to be lowered into and raised from a position within said well bore in which the cutting surface on its lower end is engaged with an obstruction about the fish, for rotating the pipe with the body so as to cause said cutting surface to remove a portion of the obstruction when so engaged therewith, and for imposing a downward load on the body to the pipe as it is so rotated, said running string also being manipulatable to release the body from the pipe for movement vertically downwardly and for rotation with respect to said pipe, whereby the connecting means on the lower end of the body may be connected with the fish and various fishing operations may be performed so as to release the fish, after which said running string may be further manipulated to support the washpipe from the body to permit the tool to be removed from the well bore with the fish.

2. A tool for use in releasing a fish stuck within a well bore, comprising a tubular body adapted to be connected to the lower end of a running string for suspension within the well bore, a washover pipe surrounding the body, an annular cutting surface on the lower end of the pipe adapted to surround the fish, means on the lower end of the body for connecting with the fish, means on the body engageable with means on the pipe for supporting the pipe for movement vertically therewith and with its cutting surface below the connecting means, whereby the pipe may be lowered into and raised from a position within the well bore in which its cutting surface engages the obstruction about the fish, means on the body engageable with the means on the pipe, while the pipe is supported thereon and in response to rotation of the body in one direction, for rotating the pipe so as to cause the cutting surface to remove a portion of the obstruction, and means on the body engageable with means on the pipe, while the cutting surface is engaged with the obstruction and in response to lowering of the body downwardly with respect to the pipe, for imposing the weight of the body on the pipe, said body being manipulatable to disengage each of said engageable means on the body and pipe so as to free the body for vertical and rotational movement with respect to said pipe, whereby the means on its lower end may be connected to the fish and various operations may be performed on the fish for releasing same, said body being further manipultatable to reengage the means on the body and pipe for supporting the pipe from said body to permit the tool to be removed from the well bore with the pipe.

3. A tool for use in releasing a fish stuck within a well bore, comprising a tubular body adapted to be connected to the lower end of a running string for suspension within the well bore, said body having a relatively small diameter upper portion, a relatively large lower diameter portion, and an annular shoulder at the intersection of said portions, a washover pipe surrounding the body and having an inner diameter fitting relatively closely about the lower portion thereof, an annular cutting surface on the lower end of the pipe adapted to surround the fish, and means on the lower end of the body for connecting with the fish, said pipe having a lug on its inner diameter, and the lower portion of the body having a slot to receive the lug when the body is in a raised position relative to the pipe so as to dispose the connecting means on its lower end above the cutting surface on the lower end of the pipe, said slot including a first generally vertical portion extending downwardly from the shoulder to receive the lug, a generally horizontal portion extending laterally from the lower end of the first vertical portions, and second and third generally vertical portions extending generally upwardly and downwardly, respectively, from the end of said horizontal portion, and said lug being engageable with the sides of each of said second and third slot portions to permit the body to rotate the pipe therewith, and being removed from the slot and opposite the upper diameter portion of the body, when the body is in a lowered position relative to the pipe, so that the body may be reciprocated and rotated free of the pipe to permit the means on its lower end to be connected to the fish and various operations may be performed on the fish for releasing same.

4. A tool of the character defined in claim 3, wherein the horizontal portion of the slot is slanted downwardly in a direction away from said first vertical portion.

5. A tool of the character defined in claim 3, wherein the upper end of the first vertical portion is upwardly flared.

6. A tool of the character defined in claim 3, including means on the upper end of the inner diameter of the washpipe for sealably surrounding the upper relatively small diameter of the body.

Claims (6)

1. A tool for use in releasing a fish stuck within a well bore, comprising a tubular body adapted to be connected to the lower end of a running string for suspension within the well bore, a washover pipe surrounding the body, an annular cutting surface on the lower end of the pipe adapted to surround the fish, means on the lower end of the body for connecting with the fish so as to lift it from the well bore, and means responsive to manipulation of the running string for supporting the pipe from the body to permit the pipe to be lowered into and raised from a position within said well bore in which the cutting surface on its lower end is engaged with an obstruction about the fish, for rotating the pipe with the body so as to cause said cutting surface to remove a portion of the obstruction when so engaged therewith, and for imposing a downward load on the body to the pipe as it is so rotated, said running string also being manipulatable to release the body from the pipe for movement vertically downwardly and for rotation with respect to said pipe, whereby the connecting means on the lower end of the body may be connected with the fish and various fishing operations may be performed so as to release the fish, after which said running string may be further manipulated to support the washpipe from the body to permit the tool to be removed from the well bore with the fish.

2. A tool for use in releasing a fish stuck within a well bore, comprising a tubular body adapted to be connected to the lower end of a running string for suspension within the well bore, a washover pipe surrounding the body, an annular cutting surface on the lower end of the pipe adapted to surround the fish, means on the lower end of the body for connecting with the fish, means on the body engageable with means on the pipe for supporting the pipe for movement vertically therewith and with its cutting surface below the connecting means, whereby the pipe may be lowered into and raised from a position within the well bore in which its cutting surface engages the obstruction about the fish, means on the body engageable with the means on the pipe, while the pipe is supported thereon and in response to rotation of the body in one direction, for rotating the pipe so as to cause the cutting surface to remove a portion of the obstruction, and means on the body engageable with means on the pipe, while the cutting surface is engaged with the obstruction and in response to lowering of the body downwardly with respect to the pipe, for imposing the weight of the body on the pipe, said body being manipulatable to disengage each of said engageable means on the body and pipe so as to free the body for vertical and rotational movement with respect to said pipe, whereby the means on its lower end may be connected to the fish and various operations may be performed on the fish for releasing same, said body being further manipulatable to reengage the means on the body and pipe for supporting the pipe from saiD body to permit the tool to be removed from the well bore with the pipe.

3. A tool for use in releasing a fish stuck within a well bore, comprising a tubular body adapted to be connected to the lower end of a running string for suspension within the well bore, said body having a relatively small diameter upper portion, a relatively large lower diameter portion, and an annular shoulder at the intersection of said portions, a washover pipe surrounding the body and having an inner diameter fitting relatively closely about the lower portion thereof, an annular cutting surface on the lower end of the pipe adapted to surround the fish, and means on the lower end of the body for connecting with the fish, said pipe having a lug on its inner diameter, and the lower portion of the body having a slot to receive the lug when the body is in a raised position relative to the pipe so as to dispose the connecting means on its lower end above the cutting surface on the lower end of the pipe, said slot including a first generally vertical portion extending downwardly from the shoulder to receive the lug, a generally horizontal portion extending laterally from the lower end of the first vertical portions, and second and third generally vertical portions extending generally upwardly and downwardly, respectively, from the end of said horizontal portion, and said lug being engageable with the sides of each of said second and third slot portions to permit the body to rotate the pipe therewith, and being removed from the slot and opposite the upper diameter portion of the body, when the body is in a lowered position relative to the pipe, so that the body may be reciprocated and rotated free of the pipe to permit the means on its lower end to be connected to the fish and various operations may be performed on the fish for releasing same.

4. A tool of the character defined in claim 3, wherein the horizontal portion of the slot is slanted downwardly in a direction away from said first vertical portion.

5. A tool of the character defined in claim 3, wherein the upper end of the first vertical portion is upwardly flared.

6. A tool of the character defined in claim 3, including means on the upper end of the inner diameter of the washpipe for sealably surrounding the upper relatively small diameter of the body.

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