US2720924A - Connecting devices for well tools - Google Patents

Description

Oct. 18, 1955 c. c. BROWN 2,720,924

CONNECTING DEVICES FOR WELL TOOLS Filed Feb. 20, 1950 /4 g g A \f, 5 5 //J W 2 g 2 3/ 23 C/cero C. Brown JNVENTOR. I

A T TORNEKS United States Patent CONNECTTNG DEVICES FOR WELL TOOLS Cicero C. Brown, Houston, Tex.

Application February 20, 1950, Serial No. 145,251

2 Claims. (Cl. 156-138) This invention relates to new and useful improvements in connecting devices for well tools and particularly for well packers.

The usual well tool, such as a well packer, which is arranged to be removably anchored or set within a well pipe ordinarily includes an anchoring assembly for supporting the tool within a well casing and it is the standard practice to detachably connect the anchoring assembly to a lowering mandrel or pipe, whereby the well tool may be lowered and raised within the outer well pipe or casing by means of said mandrel. When the well tool is to be set the mandrel is disconnected from the anchoring assembly and is lowered relative thereto and such lowering effects the setting of the locking or slip means of the anchoring assembly; thereafter in the case of a well packer the elastic packing element thereof is displaced radially outwardly into a set position.

The usual type of detachable connection which is generally employed in well tools, such as packers, is the J-slot and lug arrangement and this connection is satisfactory except that it does not provide for a lock-down of the slip means of the anchoring assembly when the latter is in a set or anchored position in engagement with the well pipe. Thus, it may occur that after the slip means is set an excessive pressure may develop above the slip means or for some other reason the slip means is urged downwardly relative to the mandrel, thereby resulting in disengagement of the slip means and a release of the well tool from its anchored position.

It is therefore one object of the present invention to provide an improved connecting device for detachably connecting a support with the anchoring assembly of a well tool and having means for preventing disengagement of the slip means by a pressure from above said means after the slip means has been engaged with the well pipe in its locked or anchored position.

An important object of the invention is to provide an improved connecting means utilizing a slot and lug connection wherein the slot is constructed in such a manner that after the anchoring means is set the slot and lug will co-act with each other to prevent release of the anchoring means by pressure or force from above the anchoring assembly.

A further object is to provide a connection between an anchoring assembly and a support comprising a slot and coacting lug, said slot having means for ordinarily urging the lug into a position locking the slip meansot the anchoring assembly against movement in a direction which would release said slip means following the setting of said slip means.

A further object is to provide a connecting device of the character described which is particularly adapted for use with well packers but which may be employed with any well tool having a releasable anchoring assembly which is adapted to support said tool within a well bore.

The construction designed to carry out the invention will be hereinafter described together with other features thereof.

2,720,924 Patented Oct. 18, 1955 ice The invention will be more readily understood from a reading of the following specification and by reference to the accompanying drawings forming a part thereof, wherein an example of the invention is shown, and wherein:

Figure 1 is an isometric view of a connecting device constructed in accordance with the invention and illustrating the lug of said device in dotted lines,

Figure 2 is a view partly in section and partly in elevation of the anchoring assembly of a well tool showing the improved connecting device applied thereto, and

Figure 3 is a horizontal cross-sectional view taken-on the line 3-3 of Figure 2.

In the drawings, the numeral 10 designates a tubular mandrel or support which is adapted to be connected with an anchoring assembly A of a well tool, such as a well packer. The anchoring assembly is subject to variation and as illustrated includes a slip carrying cage or sleeve 11 having longitudinal radially disposed slots 12 within which gripping slips 13 are mounted. Each slip has its rear surface 14 tapered or inclined and this inclined surface is adapted to coact with a slip expanding cone 15 formed on the lower end of a tubular section 16 which surrounds the supporting mandrel 1%. The section 16 is attached with the usual elastic packing element (not shown) of the well packer.

A plurality of bowed or curved friction springs 17 are disposed within recesses 18 in the external surface of the slip cage 11 and have their lower ends secured to said cage. The lower end of the cage or sleeve is illustrated as having a seal cup 19 secured thereto and said cup has downwardly flared sealing lips which seal off between the well casing C within which the assembly is adapted to be lowered. It is understood that the seal cup 19 may be omitted.

in carrying out the present invention and for the purpose of connecting the tubular mandrel it with the anchoring assembly A said mandrel is formed with an annular upset portion 21 and provides an annular shoulder 22 at its upper end. If desired the portion 21 may be in the form of a sleeve which surrounds the mandrel 1i and which is welded or otherwise secured thereto. A pair of diametrically opposed slots 23 are formed in the upset portion 21 and since the slots are identical, a description of one will sufiice. Each slot 23 is formed in the upset portion and includes an elongate central portion 24 which extends longitudinally of the upset 21. The lower end of the slot has a lateral leg 25 and one wall of the longitudinal portion 24 of said slot is merged into this lateral portion by a curved wall section 26. An offset 27 extends from the upper end of the longitudinal portion 24 of the slot and beyond the ofiset the extreme upper end of the slot extends longitudinally of the man cirel. The ofiset 27 in the slot has one wall 29 disposed in a horizontal plane, this wall being located in the upper longitudinal portion 28 of the slot. The opposite wall 30 of the slot is beveled or inclined and functions to connect the elongate central portion 24 of the slot with the upper end portion 28 thereof.

Each slot 23 is adapted to coact with a connecting lug 31 which extends inwardly from the wall of the bore of the slip carrying cage or sleeve 11 and as illustrated each lug is formed of a pin which is threaded through the wall of the cage; however, it is evident that the lug may be formed integral with the cage or secured thereto in any desired manner.

When the anchoring assembly is to be lowered within a well pipe or casing C each connecting lug 31 of the slip carrying cage 11 is engaged with the lateral leg 25 in the lower end of its respective slot and said lug engages the horizontal upper edge 25a of said lateral leg. This maintains the slip carrier 11 and its gripping slips 13 in lowered position on the mandrel and the shoulder 22 V on the mandrel functions to support the expanding cone 15, whereby said cone is in a retracted position with respect to the gripping slips 13. Thus, with the connecting lugs 31 engaged within the lateral legs of the slots 23 the slips are in a retracted position and the mandrel 10 may be employed to raise and lower the anchoring assembly A within the pipe or well casing C.

When the anchoring assembly is to be set themandrel 10 is rotated in a direction to move the connecting lugs 31 into alignment with the longitudinal central portions 24 of the slots 23 and this maybe accomplished because the slip carrier 11 will be held against rotation by the frictional engagement of the springs 17 with the wall .of the casing. Alignment of the connecting lugs 31 with the longitudinal central portions 24 of the slots will be facilitated by each lug striking the curved wall 26 which connects the lateral leg 25 with the longitudinal portion 24 of its respective slot and as the lug aligns with said longitudinal portion 24 the mandrel 10 may be moved downwardly with respect to the slip carrier. At this time the slip carrier is held against movement with the mandrel by the engagement .of the friction springs 17 with the wall of the well casing.

As themandrel 10 is moved downwardly the expanding cone 15 supported by the shoulder 22 .of said mandrel moves downwardly within the gripping slips 13 and said cone coacts with the inclined inner surfaces 14 of the slips to expand the same radially outwardly into gripping engagement with the wall of the well casing. When this occurs further downward movement of the cone 15 is prevented and a continued downward movement of the mandrel with. respect to the connecting lugs will cause said connecting lugs to strike the inclined edges of the offsets 27, whereby each connecting lug is moved by its coaction with this inclined wall into a position overlying or above the horizontal wall or shoulder 29 of the oflset. Continued downward movement of the mandrel from this point would merely move each lug 31 upwardly through the uppermost portion 28 of the slot. However, by the time each lug .31 has moved into a position above the shoulder 29 of the slot the packing unit (not shown) above the cone will have movedto a set position to prevent further downward movement of the mandrel. Thus, when the anchoring assembly and the well tool to which it is applied is in its set position each connecting lug 31 is at some point above the horizontal edge or shoulder 29 of the offset portion 27 of the slot 23.

The parts will remain in this position so long as the well tool remains in its set position within the well pipe C. However, if a pressure shoulddevelop which acts downwardly on each slip carrier 11 while the anchoring assembly is in its set position such force would tend to move the slip carrier and the slips downwardly relative to the expanding cone 15 and thiswould cause the slips or move downwardly relative to said cone whereby said slips might disengage the wall of the well casing. With the arrangement shown any downward movement of the slip carrier with respect to the mandrel will be prevented because the connecting lugs 31 will engage the horizontal edges or shoulders 29 of the slots 23 and since thiselement is a part of the mandrehdownward movement of the slips is prevented. Therefore, so long as the anchoring assembly is in its set position an unintentional downward displacement of the slip means cannot occur.

When it is desired to remove the anchoring assembly it is only necessary to rotate the mandrel in a direction to realign .the connecting lugs 31 with the longitudinal central portions 24 of the slots 23. This alginment is facilitated by the engagement of eachlug with the inclined wall 30 and thus upon rotation and lifting of the mandrel each connecting lug 31 is caused .to travel-within the longitudinal central portion 24 of its slot 23.. Continued lifting or raising of the mandrel causes the curved surface 26 of each slot 23 to engage its lug 31 and thereby guide the lug into the lateral leg 25 whereby the mandrel is reconnected to the slip carrier with the slips in their retracted position. It is noted that while the mandrel is being raised the shoulder 22 of the upset portion 21 on saidmandrel will strike the expanding cone and may be utilized to'jar upwardly on this cone to assist in retracting the cone member from within the slip members 13. It is apparent that the entire assembly may thus be removed from the well casing.

The device functions in a manner very similar to the usual J-slot and lug connection. However, each slot 23 is provided with the offset portion 27 having the lockdown shoulder 29 which coacts with the connecting lug to prevent unintentional downward displacement of the slips. With this construction a positive locking of the slip means against downward movement from its set position is provided and this is the important feature of the invention. It will be evident that the particular size and length of each slot 23 as well as the number of slots employed will be subject to some variation as will be the shape of each connecting lug 31. So long as the lateral leg 25 is formed at the lower end of each slot with the offset 27, and shoulder 29 being provided nearer the upper portion thereof the purposes of the device will be accomplished.

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

structure.

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 contemplated by and is within the scope of the claims. 7

As many possible embodiments may be made of the invention withoutdeparting 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 ina limiting sense.

Having described the invention, I claim:

l..In a well tool, a connecting device for connecting a tubular support to an anchoring assembly which anchoring assembly includes a .slip carrying sleeve surrounding said tubular support, said sleeve being provided with longitudinal radially disposed slots within which pipe gripping slips are mounted, each of said slipshaving its .rear surface downwardly and inwardly inclined and adapted to coact with a slip expanding cone formed on the lower end of a tubular member surrounding said tubular support, said expanding cone beingabove said slips, said connecting device comprising an annular ele-.

ment secured to the outer surface of said tubular support and having a slot therein, a connecting lug mounted in saidslip carrying sleeve below said slips and extending inwardly from said sleeve and co-acting with the slot of said annular element, said slot having its major portion extending longitudinally of the element and having a lateral leg' portion at its lower end and also having an elongated portion laterally offset at its upper end, a jarring surface on the upper edge of said annular ele ment, a jarring surface on said slip expander coneabove the jarring surface on the annular element and engageable therewith when said major portion of the slot is moved relative to said lug by an upward movement of said support relative .to said slip expander cone, said jarring surfaces being spaced from each other and. so positioned that the contact of said jarring surfaces occurs While the lug is in the major portion of the slot and in advance of the relative movement of said lug into said lateral leg portion, the movement of the lug into said lateral leg portion locking the lug against longitudinal movement in either direction with respect to the annular element, said slot having a curved wall at its lower end which extends from saidmajor portion to the lower edge of the lateral leg portion for moving the lug from said References Cited inthe file of this patent major portion into the said lateral leg portion by the UNITED STATES PATENTS ggli Of a non-rotafive upward p n said s p- 1,033,187 Metzger July 23, 1912 2. The structure set forth in claim 1, wherein said 5 21221749 Nlornsett y 1938 slot has another curved wall at it upper end whi h x- 213681400 Baker J@111- 1945 tends from said major portion upwardly at an angle to g i 12 3?] the longitudinal axis of the support to move the said lug 2:595:563 BT55; g-y 6: 1952 from said major portion into said laterally ofiset portion by the application of a downward non-rotative move- 10 ment of the support.

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