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Publication numberUS3382929 A
Publication typeGrant
Publication dateMay 14, 1968
Filing dateNov 22, 1965
Priority dateNov 22, 1965
Publication numberUS 3382929 A, US 3382929A, US-A-3382929, US3382929 A, US3382929A
InventorsPlunk Rowe A
Original AssigneeRowe A. Plunk
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Oil well tools
US 3382929 A
Abstract  available in
Images(2)
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Claims  available in
Description  (OCR text may contain errors)

R. A. PLUNK OIL WELL TOOLS May 14, 1968 2 Sheets-Sheet l Filed Nov. 22, 1965 R. A. PLUNK OIL WELL TOOLS May 14, 1968 2 Sheets-Sheet 2 Filed Nov. 2 1965 INVENTOR. Row; A. PLUNK Awa United States Patent 3,382,929 OIL WELL TOOLS Rowe A. Plunk, P.O. Box 1167, Midland, Tex. Filed Nov. 22, 1965, Ser. No. 509,059 8 Claims. (Cl. 166-214) ABSTRACT OF THE DISCLOSURE This invention relates to an oil well tool. More specifically, the invention relates to an automatic anchoring device for use in conjunction with other wire line tools to arrest upward travel in an oil well such as may be caused by upward flowing fluids. Another aspect of this invention is to provide a tool that will automatically anchor or hang upon slackening of the supporting means; hence this novel tool will permit the dynamic analysis of an oil well during actual working conditions with no danger of a tool string either moving about during the test or being thrust up-hole by the iluid flow of the w ll.

During a live or dynamic well test in which a string of tools are located down-hole and suspended from a wire line, the flow of fluid through the tubing and past the string of tools sometimes becomes of such a magnitude that the entire tool string is thrust up-hole, thereby entangling the wire and tools which often results in the entire assembly becoming lodged in the tubing. Another problem involved in well analysis is movement of the tool string relative to the well casing, whereupon direction and vertical location of the tool string is not held to an absolute constant. The novel tools of the instant invention overcomethese difiiculties when ,the tools are connected in tandem in the wire line tool string.

Summary of the invention I have invented a tool to operate in this environment. The tool according to my invention has dogs mounted upon the toggle which are normally held retracted by the tension of the wire line supporting the tool. However, should the tool be blown upward, springs will push the dogs outward where, by their toggle action, they will lock the tool to the tubing, thus preventing further damage. Also the tool has another section containing an anchoring device whereby the tool may be anchored in normal operation. The anchoring device likewise is held inactive by normal tension in the line.

An object of this invention is to provide an automatic anchoring device for a tool string that arrests thrust uphole of the tool string as a consequence of the well fluid flow.

Another object of this invention is to provide a wire line tool accessory that will automatically anchor itself to the tubing wall whenever the wire line becomes slack; i.e. when the tension on the Wire line near the tool string approaches zero. A further object of this invention is to provide an oil well tool having a toggle joint that includes two dogs that provides an anchoring means in response to the amount of tension in the tool suspension system.

Another object of this invention is to p ovide an oil well tool that will permit positive suspension of a tool string from the tubing wall at the desired well depth under study.

A further object of this invention is to provide an 3,382,929 Patented May 14, 1968 anchoring tool that will engage the casing wall upon a brisk slackening of the wire line.

A particular object of this invention is to provide a combination hanging and arresting tool wherein the instant hanging tool and arresting tool are placed in tandem in a tool string to thereby provide a tool that will anchor itself to the well casing in response to either thrust up-hole conditions or a lack of tension in the support means.

Still another object of this invention is to provide a hanging tool that includes an additional means that will prevent actuation of the tool until the direction of travel of the tool is reversed.

The various features of construction and arrangement involved in the instant oil tool will become apparent from the drawing and specification, wherein; on the drawing:

FIGURE 1 shows an elevational view of the wire line arrestor tool placed in tandem with the hanging tool and with the dogs of the toggle joint of each of the tools shown in extended position.

FIGURE 2 is an exploded partially sectional view of the arrestor tool.

FIGURE 3 is a perspective view of the toggle joint of the arrestor tool.

FIGURE 4 shows the toggle joint of FIGURE 3 in retracted position.

FIGURE 5 is an exploded partially sectional view of the hanger tool of FIGURE 1.

FIGURE 6 shows the toggle joint of FIGURE 5 in the partially extended position.

Referring now to the drawings in greater detail, there is seen in FIGURE 1 the arrestor tool 1 and the hanger tool 67 which are adapted to be included anywhere along a string of tools. For example, there may desirably be other tools attached at both pin 2 and box 3, depending upon the specific tool requirements involved in a particular well test. In other words, the purpose of the well study may involve, for example, a perforating job to be carried out at a certain depth. In such a specific case, an orientating device may be advantageously attached at pin 2 while a string of guns may be suspended from box 3. In another and different test, the pin 2 may be directly attached to a cable thimble, while box 3 carries logging instruments. The dogs 4 are shown in extended position since the arrestor tool is illustrated as being in the noload or unsuspended condition.

Looking now to FIGURE 2, wherein the arrestor tool 1 of FIGURE 1 is shown in disassembled condition. The body 9 has a box connection 3 that may be either a straight or seizing taper and is adapted to carry a string of tools suspended therefrom, as for example, instruments, guns, or the like. The body 9 is additionally provided with a slot 10 having a hole 11 drilled diametrically therethrough to accommodate spring pin 5, and a counterbore 12 forms a passageway communicating the upper end of the body 9 and the slot it The end of counterbore 12 is threaded as at 13 to match the mating threads 14 of counter'oored retaining nut 15. The body 9 carries therewithin a traversing mandrel 20 that is slidably located longitudinally within passageway 12. The traversing mandrel has a shoulder 21 machined thereon and a yoke 22 formed at the end havin a yoke pin aperture 23 drilled diametrically therethrough. The mandrel 20 has a. shaft 25 that fits in close tolerance relationship to passageway of nut 15 and carries threaded surface 26 that mates with the threads 16 of the sub 8.

Looking now to FIGURE 3 in conjunction with FIG- URE 2, there appears at yoke 22 a toggle joint 30 comprised of two dogs 31 and two links 33. The dogs 31 each have teeth 32 machined thereon to provide engagement against a well casing or tubing when expanded in an outward direction. An indentation or dimple is provided on the dog and the swing end of the link at 37 and 33 respectively to provide a captive ball joint in conjunction with a ball 35. Each link is apertured as at 36 to provide a common link pivotal point whereby spring pin 5 may be driven through the hole I]. of the body and holes 36 in each link to retain the links by the common pin 5. The opposite end of the dogs 31 are apertured to accommodate pin 23 in yoke 22. Thus it is now apparent that the two junctions 36 and 23 may be moved toward and away from one another to extend or retract the dogs from or into the slot It? of body Since pin 23 attaches to yoke 22 and pin 5 attaches to the body at 11, longitudinal movement of mandrel 20 relative to body 9 will actuate the dogs 31 in the above described manner. A spring 17 abuts shoulder 21 of the mandrel and face 18 of retaining nut to provide a force that tends to move the mandrel yoke 22 away from the nut 15. With the body 9, mandrel 20, nut 15, and sub or box and pin connector 8 in assembled relationship, the mandrel is slidably located within the body 9 and nut 15, whereby motion along the longitudinal axis of the passageway 12 as effected by the sub d will slide the mandrel and sub in an up and down or longitudinal direction relative to the body and retaining nut. With the toggle joint in fully retracted position, that is, tension being exerted by the wire line at sub 8, the shaft 25 will accordingly be visible between sub 8 and nut 15 with the shaft shoulder 21' providing a first stop means by abutting face 18 of nut 15. When the assembly is under no-load condition, that is, the wire line is slack, the dogs will then be fully extended with the second stop means being provided by the yoke abutting the end of counterbore 12 as illustrated at 39 in FIGURE 2 where the counterbore ends inside the slot 10.

In operation, the tool is suspended from a wire line by the pin of sub 8. The weight of the tool causes the mandrel to abut the first stop means in opposition to the force of spring 17. The upward movement of the mandrel with respect to the body retracts the dogs of the toggle joint, and the tool remains in this condition under normal conditions of usage so long as the tension of the wire line springs the sub away from the body of the tool.

Should the well under survey suddenly have a large surge that exceeds a value greater than is provided for by the large by-pass area about the tool resulting in thrust up-hole of the tool string, the tool will almost instantaneously arrest this upward travel since the instant the wire line tension drops to a value less than the compression force of the spring 17 a downward force will be exerted on the toggle joint by the mandrel which will be forced in a downward direction by the spring; the dogs will accordingly extend laterally of the tool and engage the well tubing, thereby arresting thrust upwards.

The initial movement of the dogs as compared to the movement of the mandrel is of a very large initial ratio; and as the links approach the horizontal this ratio becomes progressively smaller, since the action of the toggle joint changes the direction of the vertical force that is applied at the yoke pin by the spring to a horizontal force at the dog and provides an enormous mechanical advantage as the links approach this horizontal position. The links and dogs are sized according to the inside diameter of the casing used in conjunction with the tool. For example, the following tool worked satisfactorily in a well having a 2 inch ID. casing; 1.25 inch diameter body; 1.70 x 0.50 inch slot having a pin hole 0.5 inch from the upper extremity thereof; link 0.65 inch between hole and indentation; center dog 0.7 inch between hole and indentation, 1.45 inch overall length. In wells having tubing of other sizes, the dogs and links must be of a size that will enable the links to approach the horizontal position upon contact with the tubing wall so as to effect a large mechanical advantage of the spring pressure as related to the force exerted by the dogs by the toggle joint; i.e.;

the spring force is amplified by the toggle joint to provide a large arresting force by the dogs.

The toggle joint provides the function of changing the direction of an applied force from vertical to horizontal so as to enable the dogs to exert an enormous amount of arresting force against the tubing wall. This applied force is the downward compression force of spring 17 exerted against the yoke 22 at pin 23'. Looking at FIGURE 3, and visualizing this force as being at pin 23, it will be noted that the links 33 are approaching the horizontal as regards the alignment of their pivotal and swing joints 34 and 36 respectfully. Since the dogs 31 are engaging the casing at this position, an enormous pressure is accordingly being exerted by the dogs against the casing because of this relationship between the links. Hence the toggle joint 30 can multiply the spring force many times so as to provide a powerful arresting force when the wire line becomes slack.

Now looking at the embodiment of FIGURE 5 in detail, there is seen a hanging tool that incorporates several of the novel features depicted in the novel device of FIG- URES 1 through 4. This novel hanging tool permits a tool string to be statically located at a specific depth down-hole in the well. In well logging and perforating it is often desirable to positively locate a tool string with respect to the well tubing or casing since the wire line, because of its extreme length, is inherently highly resilient and accordingly small movements inadvertently applied to the wire line at the well head will impart larger movements to the tool string located down-hole in the well. Additionally, once the tool string is properly orientated with respect to the well, the instant invention provides the highly advantageous function of positively fixing this desired position of the tool string. Another important advantage of the instant novel hanging tool is the ability of the tool to anchor itself to the well casing in the event the tool string suspension means fails.

The hanging tool of FIGURE 5 is comprised of a body 9 having guides 54 placed thereon, a retaining nut 15' that receives the shaft of mandrel 67', and a sub 8' having a box connection at one end to mate the threaded ext-remity of the mandrel. A pin connection is provided at the other end from which the tool may be suspended. The mandrel slidably fits into the upper end of the body in a manner set forth for the embodiment of FIGURE 2, and connects to a toggle joint 40 (the details of which are seen in FIGURE 6). The lower extremity of the toggle joint attaches to 59 in a spring loaded follower 51.

T he mandrel 67 is similar to that of FIGURE 2 and additionally includes an off-set yoke as seen at 68 to provide for a centering link 41. This off-set feature is best seen in FIGURE 6 at numerals 64 and 68.

As seen in both FIGURES 5 and 6, the novel hanging tool includes a toggle joint 40 having a second spring 53 in compression against a second traversing mandrel or follower 51. The second spring 53 is of a lower strength as compared to the spring 17' that actuates the first traversing mandrel 67. The second spring 53 fits inside the follower 51 and retainer nut at 65 in abutting relationship between the face and the face 66. The body 9' is provided with a second counter bore 52 which carries threads 56 at the lower extremity thereof to mate with the threads 57 of the second retainer nut 5d, the purpose of this last nut is to provide a means of assemblying the second traversing mandrel, dogs 47, and spring 53, which enter the body counter bore 52 from the threaded end 56 and are held in place by nut 58. The follower 51 is provided with a yoke 59 having a pin hole 60 drilled diametrically there-through to receive pin 49 that hold dogs 47 which are held in the aperture 60 by the swing end thereof.

The toggle joint 40 includes a centering link 41 that connects the remainder of the toggle joint to the yoke by apertures 62 and 63. The master link 44 attaches to the centering link by pin 63' and to a first dog 47 by either a captive ball joint or an articulated link 45 as shown. The second dog is connected to the master link 44 by link 46 which also has an articulated link at 48. The pin aperture 43 aligns with diametric aperture 11' in slot to provide a common pivotal point for elements 44 and 46 when the spring pin 43 is driven therethrough. The ends of the dogs are connected to a follower or second yoke 59 located in the upper extremity of the follower or second mandrel 51, as already set forth in detail above.

In both the arrestor tool and the hanging tool, the mandrel springs may be eliminated if desired since either tool will still work without the springs because the suspension force will maintain the toggle joint in retracted position. The prevailing force that actuates each of the tools; i.e., thrust up-hole on the no-blow tool or the gravitational force on the hanger tool; will act on the articulated links to control the action of the dogs, and the greater is the magnitude of the force, the stronger will be the grip of the dogs. The follower spring may not be eliminated from the hanger tool since the follower is pivotally attached to the dogs and in order to start the swing ends of the dogs towards the tubing a bias must be provided, for the pivotal points between the mandrel and the master link are too well aligned when the dogs are retracted to cause any positive action from a biased mandrel. The mandrel spring is desirably used in each of the instant tools, however, for the relative motion caused by the spring action moves the mandrel and its attachment toward the tool body and its attachment, and where a weight is relied upon in lieu of a spring, the momentum of the body and its attachments must encounter the inertia of the mandrel and its attachment before the dogs may be actuated, hence it is readily apparent that the response rate is substantially increased where a spring loaded mandrel is employed in either tool.

Thus, as indicated above, the hanger tool and arrestor tool may be placed in tandem in a tool string to provide a hanger which requires a mere slackening of the wire line for its actuation, and to provide an arresting tool that anchors itself to the tubing wall at the onset of a thrust upwards sufiicient to slow its travel to a value where the wire line becomes slack. The novel combination of these two tools in a tool string not only enables the wire line operator to positively locate the tool string at any given depth, but also prevents the tool string from being thrust up-hole. More importantly, should the wire line part, the tool string will instantly hang in the casing, thus providing easy retrieval by a simple and elementary fishing job.

It should be understood that the present disclosure is for the purpose of illustration only and that this invention includes all modifications and equivalents which wall within the scope of the appended claims.

Also, it will be apparent that the balls 35' are held in the depressions 37 and 38 by the fact that the dogs 31 and the links 33 are confined within the slot 10 and are unable to move away from one another thus releasing the balls 35.

Another such change which could be made would be to make the pin 23' of soft material so that it would act as a shear pin in case the tool because of obstructions tended to become stuck in a well. In such event the primary strain would be upon the first stop means of 21 and 18. Also, in such a change, the dogs 31 would be provided with sufiicient clearance so that the pin 36 could move above the balls 35 to permit retraction of the toggle in this fashion.

I claim:

1. A wire line tool including an automatic anchoring device comprising a body having a toggle joint operatively associated therewithin; said toggle joint including retractable anchoring means; means associated with said body and said toggle joint for retaining said anchoring device in retracted position when said body is under wire line tension and to actuate said anchoring device when said body is free of wire line tension, said body including a cylindrical steel cylinder having a slot machined into the central portion thereof and a longitudinally drilled passageway connecting the slot with an end thereof, the last named end including a threaded internal surface adapted to receive a counter-bored retaining nut, a mandrel having a shaft and yoke, said toggle joint including means to be fastened in the yoke of the mandrel and located in said slot with said mandrel shaft being slidably received in the counter bore of said nut, whereby; tension applied to said mandrel shaft maintains said toggle joint in retracted condition and wherein release of said tension causes said toggle joint to expand radially away from said body, the toggle joint including two identical dogs and two identical links; said body being provided with a pin, said dogs each having casing engaging means at one extremity, a first apertured pin means at the other extremity, and a second apertured pin means at a point intermediate said first and second extremity; a first pin located transverse to said mandrel and mutually connecting said first apertures in said dogs at said yoke to thereby permit said dogs to swing about said pin in a limited are, said links connecting said second hole to said pin located in said body and parallel to said pin in said yoke, whereby longitudinal reciprocating movement of said mandrel with respect to said body causes said toggle joint to retract into the slot in said body in one direction of movement and to extend away from said body in an opposite direction of movement to thereby provide an anchoring action between the tool and adjacent casing wall.

2. The apparatus recited in claim 1 wherein the configuration of the dogs and links of said toggle joint with respect to the well casing permits said links to approach over the center movement of the links as compared to a line drawn between the second recited pins when said toggle permits said dogs to approach full extended position.

3. The device of claim 2 wherein the mandrel is provided with a shoulder adjacent the yoke and a coil spring is located peripherally and longitudinally about the mandrel, the ends of said spring being in abutting relationship to said shoulder and said retaining nut to provide a force between said mandrel and said body; whereupon, said toggle joint is maintained in retracted position so long as said tool is hung in tension from said mandrel; whereby, said spring will expand said toggle joint upon upward motion of said tool under conditions of thrust up-hole.

4. A wire line tool including an automatic anchoring device comprising a body having a toggle joint operatively associated therewithin; said toggle joint including retractable anchoring means; means associated with said body and said toggle joint for retaining said anchoring device in retracted position when said body is under wire line tension and to actuate said anchoring device when said body is free of wire line tension, said body including a cylindrical steel cylinder having a slot machined into the central portion thereof and a longitudinally drilled passageway connecting the slot with an end thereof, the last named end including a threaded internal surface adapted to receive a counter-bored retaining nut, a mandrel having a shaft and yoke, said toggle joint including means to be fastened in the yoke of the mandrel and located in said slot with said mandrel shaft being slidably received in the counter bore of said nut, whereby; tension applied to said mandrel shaft maintains said toggle joint in retracted condition and wherein release of said tension causes said toggle joint to expand radially away from said body; the toggle joint including two identical dogs each having casing engaging means and a pin hole at one extremity, a second pin hole at the other extremity, a first pin located transverse and through said mandrel and connecting to said toggle joint, a second longitudinally drilled passageway separated from said first passageway by said slot, a spring loaded follower having a second yoke and located in said second passageway, said second pin holes pivotally located in said second yoke and providing a pivot point for said dogs, said means to be fastened in the yoke including links connecting said pin hole in said dogs to said first named yoke, whereby; tension applied to said mandrel maintains said dogs in retracted position as opposed to the extended and hanging position.

5. The device of claim 4 wherein said links include a first link, a second link, and a master link interconnected to said yoke by said first link, spring loaded means including a component external of said body and biasing said master into the retracted position, whereby; slackening of said tension permits actuation of said toggle joint.

6. A wire line tool including an automatic anchoring device comprising a body having a toggle joint operatively associated therewithin; said toggle joint including retractable anchoring means; means associated with said body and said toggle joint for retaining said anchoring device in retracted position when said body is under wire line tension and to actuate said anchoring device when said body is free of wire line tension, said body including a cylindrical steel cylinder having a slot machined into the central portion thereof and a longitudinally drilled passageway connecting the slot with an end thereof, the last named end including a threaded in ternal surface adapted to receive a counter-bored retaining nut, a mandrel having a shaft and yoke, said toggle including means to be fastened in the yoke of the mandrel and located in said slot with said mandrel shaft being slidably received in the counter bore of said nut, whereby; tension applied to said mandrel shaft maintains said toggle joint in retracted condition and wherein release of said tension causes said toggle joint to expand radially away from said body; the toggle joint being additionally connected to a spring loaded follower, said follower and said mandrel being separated by said toggle joint, whereby; brisk slackening of said wire line tension extends said anchoring means to permit said device to hang fast to a casing structure.

7. For use in a wire line tool string, an automatic anchoring device to prevent thrust up-hole of the tool string comprising; a body, a retaining nut adapted to be threaded into the upper portion of said body, a pin and box connection adjacent said nut, and a mandrel having a yoke at the lower end thereof and carrying a toggle joint partially within said yoke; said body having a box connection at the lower extremity thereof and adapted to cariy a string of tools, a slot containing said toggle joint located between said lower box connection and said threaded upper portion of said body; said body including means forming a passageway between said slot and said nut; said mandrel having a threaded surface at the upper end adapted to mate with the box of said pin and box connection; a biasing means in forceful abutting relationship between said yoke and said pin and box connection; said mandrel being adapted to telescopingly and reciprocally slidably fit in said passageway; said toggle joint including two dogs, each having anchoring means at one end and a pin means mutually movably securing said dogs; said toggle joint also ineluding a link movably attaching each dog by a ball joint located centrally of said dog to a mutual pin in said body; whereby, movement of said mandrel toward said last named pin causes said dogs to be forced outward against a tubing wall to thereby provide an arresting action between the tubing wall and the anchoring device.

8. In combination, a wire line device for use in a tool string, comprising an arresting tool that prevents thrust up-hole of the tool string and including a slotted body having a reciprocating mandrel centrally located therein, a sub connected to said mandrel, a toggle joint means including a pair of transversely arranged dogs located in said slot and in cooperative relationship to said mandrel whereby the movement of said mandrel actuates said dogs through said toggle joint to provide an arresting action when the tool string is thrust upwards, said sub being threadedly engaged and suspended from a hanging tool, said hanging tool having a slotted body having a reciprocating mandrel centrally located therein, a sub connected to said mandrel, a toggle joint means including a pair of transversely arranged dogs located in said slot and in cooperative relationship to said mandrel whereby the movement of said mandrel actuates said dogs through said toggle joint to provide a hanging action when the tool string is rapidly lowered; suspension means at the top of said hanging tool; and attachment means at the bottom of said arresting device to provide carrying means for wire line accessory tools.

References Cited UNITED STATES PATENTS 1,503,693 8/1924 McLean 166206 X 2,108,174 2/1938 Mays 166-212 X 2,141,030 12/ 1938 Clark 166212 X 2,170,284 8/1939 Eastman 166-206 X 2,639,893 5/1953 Pigott 166211 2,672,200 3/1954 Patterson l66-206 X 3,052,297 9/1962 Blydorp 166-436 X FOREIGN PATENTS 637,335 2/1962 Canada.

CHARLES E. OCONNELL, Primary Examiner.

DAVID H. BROWN, Assistant Examiner.

Patent Citations
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Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US4028796 *Jun 23, 1976Jun 14, 1977Arthur Everett BergstromFor oil well production tubing
US4141386 *Jul 31, 1975Feb 27, 1979Bergstrom Arthur EBlast joint
US4997038 *Nov 27, 1989Mar 5, 1991Otis Engineering CorporationLock mandrel latch assembly
US6318462 *Mar 2, 2000Nov 20, 2001Conelly Financial Ltd.Downhole anti-rotation tool
US6681853Sep 26, 2001Jan 27, 2004Msi Machineering Solutions Inc.Downhole anti-rotation tool
US6968897 *May 9, 2003Nov 29, 2005Msi Machineering Solutions Inc.Anti-rotation tool
US7451827 *Sep 19, 2006Nov 18, 2008Gustavo Ignacio CarroAnchoring device for casing procedures in well bores
WO2001090530A1 *May 25, 2001Nov 29, 2001Ferguson StuartBraking device for tool strings
Classifications
U.S. Classification166/214, 166/243
International ClassificationE21B23/01, E21B23/00
Cooperative ClassificationE21B23/01
European ClassificationE21B23/01