US2940525A

US2940525A - Removable stop for well tools

Info

Publication number: US2940525A
Application number: US754418A
Authority: US
Inventors: John V Fredd
Original assignee: Otis Engineering Corp
Current assignee: Otis Engineering Corp
Priority date: 1953-10-09
Filing date: 1958-08-11
Publication date: 1960-06-14
Anticipated expiration: 1977-06-14

Description

June 14, 1 960 J. v. FREDD 2,940,525

REMOVABLE STOP FOR WELL TOOLS Original Filed Oct. 9, 1953 Fig. 2 ig. I INVENTOR.

John V. Fredd A TTORNEY REMOVABLE STOP FOR WELL TOOLS John V. Fredd, Dallas, Tex., assignor to Otis Engineering Corporation, Dallas, Text, a corporation of Texas Original application Oct. 9, 1953, Ser. No. 385,248. Divided and this application Aug. 11, 1958, Ser. No. 754,418

8 Claims. (Cl. 166-219) This invention relates to new and useful improvements in means for positioning and supporting well devices in well flow conductors such as well tubing or casing or the like, and this application is a division of my co pending application Serial No. 385,248, filed October 9, 1953.

One object of the invention is to provide a new and improved stop for positioning or supporting well devices in a well flow conductor.

An important object of the invention is to provide a well device adapted to serve as a stop or support for well tools or to close the bore of an open ended well conductor, and which device may be readily and quickly lowered into the well conductor by flexible line lowering means and anchored in position therein at the recess at a collar connecting two adjacent sections of the conductor.

A particular object of the invention is to provide a well device of the character described having stop and supporting dogs which are adapted to be expanded into locking position by a resiliently biased expanding member and wherein means is provided for rendering said expanding member inoperative until the device has been lowered into the well conductor to the desired position.

A further object of the invention is to provide a well device of the character described wherein the means for holding the expanding member against expanding movement with respect to the stop dogs is releasable upon the upward movement of the tool in the well tubing or conductor.

A further object of the invention is to provide a well device of the character described which is designed to provide an obstruction to the passage of well tools down- .wardly out the open end of the well flow conductor but which also permits substantially full flow of well fluids upwardly through the conductor so that the device does not appreciably restrict the flow of gas and liquids from the well through the conductor.

Additional objects and advantages of the invention will be readily apparent fi-om the reading of the following description of a device constructed in accordance with the invention, and reference to the accompanying drawings thereof, wherein:

Figure 1 is a view partly in elevation and partly in section showing a well device or a stop constructed in accordance with the invention as it appears while being lowered in a tubing string; and

Figure 2 is a view partly in elevation and partly in section showing the stop as it appears locked in position in a well flow conductor.

Referring now to the drawings, the numeral 10 designates a stop having a body 11 which is provided with a threaded upper end 12 by means of which it may be secured to the lower end of a well tool or lowering mechanism. A lock mandrel 13 is threaded in a bore 13a in the lower end of the stop body, and a plunger rod 14 is positioned in said bore and extends downwardly through said mandrel. The lower end of the plunger rod extends below the lock mandrel, and a cup-like dog carrier 15 having an upwardly extending circular wall or lip 15a is I United States Patent 0 Patented June 14, 1960 ice secured on said plunger rod below said lock mandrel by a nut 16 threaded on the lower end of the rod. The bore of the dog carrier is provided with an internal annular flange 17 which confines the hooked lower ends 18 of a plurality of stop dogs 19 between the flange and the plunger rod to hold the dogs in position in the carrier.

The upper ends of the dogs are free to move inwardly toward the plunger rod and may engage the frusto-conical expander surface 20 at the lower end of the lock mandrel when the dog carrier and the dogs are moved downwardly relative to the mandrel to the retracted position shown in Figure l. The beveled inner upper ends 21 of the stop dogs abut the downwardly facing annular wedge and lock shoulder 22 located above the frustoconical shoulder 20 of the lock mandrel when said stop dogs are moved upwardly relative to said mandrel to expand said dogs to the locking position shown in Figure 2.

The upper end of the plunger rod extends upwardly into the bore 13a of the body and'is enlarged and bifurcated to provide a pair of upwardly extending legs 23. A toggle plate 24 is rotatably mounted between the legs on a pin 25 extending through the legs and protrudes laterally into a pair of opposed

longitudinal slots

26 and 27 through the walls of the body. One slot 27 is elongated and extends downwardly beyond to the other slot 26. A release dog 28 is pivotally secured at one end by a pin 28a to the toggle plate, and the other end of the release dog is adapted to extend laterally outwardly of the elongated slot 27 beyond the body. A release spring 29 has its opposite ends rigidly secured to the pivot pin 25 and to the release dog and urges the dog outwardly in a clockwise direction for a purpose which will be hereinafter explained. v i

A link 39 has its opposite ends pivotally secured to the toggle plate 24 and to a link pin 31 extending transversely through the body above the toggle plate. A spring 32 surrounds the upper part of the plunger rod and bears at its upper end against the enlarged upper part of the rod and at its lower end against an internal shoulder 33 in the bore of the lock mandrel 13 whereby the spring urges the plunger rod upwardly relative to the body, and thus biases the carrier 15 and the dogs supported thereby upwardly into expanding engagement with the'expander surface 20 at the lower end of the lock mandrel 13.

The link 30 is connected to'the toggle plate by a pivot pin 34 displaced from the pin 25 whereby movement of the plunger rod downwardly in the body causes the toggle plate to be rotated in a counter-clockwise direction. The plate is further rotated in a counter-clockwise direction until a stop shoulder 35 on the edge of the toggle plate engages the lower end 36 of the slot 26 in the body. In this position the pivot pin 34 is displaced slightly to the left of the pin 25 and of the link pin 31 attaching the upper end of the link to the body so that the spring 32 biases the plate for rotation in a counter-clockwise, direction when the device is in the position of Figure 1.

When the toggle plate 24 is rotated in a clockwise direction through a small angle by the release dog 28, the pivot pin 34 forming the point of pivotal attachment of the lower end of the link 30 to the toggle plate is displaced slightly to the right past a dead center position between the pin 25 and the link pin 31 forming the point of pivotal attachment of the upper end of the link to the body. At this time the toggleplate will be rotated in a clockwise direction to the position shown in Figure 2 by the upward force exerted by the spring 32. The link is provided with a'notch 37 intermediate its ends in which the pin 25 is stopped on upward movement of the plunger rod, providing for suflicient rotation of the toggle plate to permit full upward retractive movement of the plunger rod, as shown in Figure 2.

In use, the stop body 11.is supported by the usual nal movement of said control means, said stop-dogs having stop shoulders thereon disposed to engage the up wardly facing shoulder in said conductor when in expanded po'sition to prevent downward longitudinal movement of the stop in the conductor.

4. A well tool' for use in a' well string having an internal upwardly facing shoulder and an internal downwardly facing shoulder, said tool including: a tubular body having a longitudinal bore; a central member in said bore mounted for movement longitudinally therein; stop means carried by said central member movable laterally from a retracted position to a projecting position; laterally projecting boss means on said stop means engageable with the upwardly facing shoulder in said well string when said stop means is in said projecting positio'n to limit downward movement of said well tool in said well string; expander means on said body engaging said stop means to move said stop means to said projecting position when said central member is moved longitudinally in one direction in said body; resilient means on said body engaging said central member for biasing said central member longitudinally in said one direction to move said stop means to projecting position; locking means cohnected with said body and said central member for preventing movement of said central member longitudinally of said body in said one direction from a position holding said expander means out of expanding engagement with said stop means; and means carried by said locking means engageable with the downwardly facing shoulder in said well conductor for releasing said locking means to permit longitudinal movement of said central member in said one direction; the boss means on said stop means having external beveled surfaces at the upper end thereof for camming said sto'p means inwardly toward retracted position upon meeting obstructions during upward movement of the tool in said well string.

5. A well tool including: a tubular body having a longitudinal bore; a central member in said bore movable longitudinally therein; stop means on said central member movable laterally from a retracted position to a projecting position; boss portions on said stop means engageable with an upwardly facing shoulder in a well string when said locking means is in said projecting position; wedge means on said body engageable with said stop means to move said stop means to projecting position when said central member is moved longitudinally to a first position; resilient means in said body engaging said central member for biasing said central member longitudinally in said body toward said first position; means on said central member preventing movement of said stop means beyond said projecting position; said central member having a reduced exterior portion permitting movement of said stop means to retracted position when said central member is in a second position in said body; an external beveled surface on said stop means whereby said stop means is cammed inwardly toward retracted position upon meeting obstructions; and release means in said body releasably holding said central member in said second position, said release means including a member engageable with a downwardly facing shoulder in the well string to release said release means and free said central member for movement in the body toward said first position upon upward movement of the well tool in said well string.

6. A well tool including: a tubular body having a longitudinal bore; a central member in said bore movable longitudinally therein; stop means on said central member movable laterally from a retracted position to a projecting position; boss portions on said stop means engageable with an upwardly facing shoulder in a well string when said stop means is in said projecting position; wedge means on said body engageable with said stop means to move said stop means to projecting posi tion when said central member is moved longitudinally to a first position; resilient means in said body engaging said central member for biasing said central member longitudinally in said body toward said first position; means on said central member preventing movement of said ,stop means beyond said projecting position; said whereby said stop means is cammed inwardly toward retracted position upon meeting obstructions; and release means in said body releasably holding said central member in said secondposition; said release means having a release dog projecting outwardly from said body and engageable with a downwardly facing shoulder in said well string on upward movement of said tool in said well string to actuate said release means to permit movement of said central member toward said first position.

7. A well tool including: a body having a longitudinal bore; a central member in said bore movable longitudinally therein; a cup-shaped member on the lower end of said central member; stop means swingably mounted in said cup-shaped member for movement of the upper ends of said stop means outwardly from a retracted po sition to a projecting position; outwardly extending boss portions providing a shoulder thereon on said stop means engageable with an upwardly facing shoulder in a well string when said step means is in said projecting position; expander means on said body engageable with the upper ends of said stop means to move said stop means to said projecting position when said central member is moved longitudinally upwardly in said body; said expander means being movable out of expanding engagement with said stop means when said central member is moved longitudinally downwardly in said body whereby said stop means may move to said retracted position; resilient means on said body engaging and biasing said central member longitudinally upwardly in said body; means on said stop means and said cup-shaped member limiting outward pivotal movement of the upper ends of said stop means; link means in said body connected between said body and said central member and releasably holding said central member in its lower position against the biasing force of the resilient means; release means connected with said link means engageable with a downwardly facing shoulder in the well string upon upward movement of the well tool in said well string for moving said link means from position holding said central member in its lower position relative to said body to free the resilient means to move said central member upwardly to its upward position in said body whereby the stop means are moved to expanded position.

8. A well tool including: a body having a longitudinal bore and a lateral aperture communicating with said bore; a central member in said bore movable longitudinally therein, the lower-end of said central member extending below said body; resilient means in said body engaging said body engaging said central member and biasing said member for longitudinal movement upwardly in said body; link means in said bore connected to said central member and said body and releasably holding said central member in a lower position on said body against the upward biasing force of said resilient means; release means connected with said link means and having one end extending outwardly and upwardly of said body through said aperture when said central member is in said lower position; spring means on said link means engageable with and biasing said release means outwardly of said body; said one end of said release means being eugageable with a downwardly facing shoulder in the well flow conductor on upward movement of the well tool to free said link means for movement from holding position to a released position to permit said central mem- "members pivotallymounted at their'lower' nd's ims'aid 5 i 5 UNITEDgS'TAiE PATENT"; cup means and ext endmg' upwardly therefrom whereby the pper ends of said stop members may move laterally 19951254 E m ---V--"-'" 1935 from a retracted position tp an" expzinded P S pander means on said body engageabl with stop 2 401 members 'when said central member is moved upw rdly 0 3 933; whereby said stop members are moved to saict expanded position; and outwardly extendingboss portions heivifig