US2603295A

US2603295A - Well packer

Info

Publication number: US2603295A
Authority: US
Publication date: 1952-07-15
Anticipated expiration: 1969-07-15

Description

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2 SHEETS-S-EET 1 llllllllll III IIIIII WELL PACKER J. D. WHHTTEN .Ey l5, H952 Filed April 7, 1947 J. D. WHITTEN WELL PACKER 2 Sl-iEETS- ShEET 2 Filed April 7, 1947 Patented July 15, 1952 UNITED TNT OFFICE This invention relates to oil or gas drilling and more particularly to well tools taking the form of packer holding devices oi the releasable type capable of utilizing the performance of many operations in preparation for pumping iiuid below the packer within the well casing such as cementing, acidizing, testing the casing for defects and other break-downs where it is desired to completely seal off a portion of the well casing from another portion thereof. The most important object of this invention is to provide a well packer capable of being set from a point on the surface, released, and reset as desired without the necessity of removing the packer from the well.

Another important object of this invention is to provide a well packer settable from the surface of the well bore upon rotation of the running-in string in one direction and upon subsequent application of longitudinal upward movement thereto.

A iurther object of this invention is the provision of a well packer releasable from the surface of the well bore after the same has been set within the well casing, either by exerting downward longitudinal force upon the running-in string and then rotating the string in a direction opposite to the direction of rotation for setting the packer, or upon further rotation of the running-in string in the same direction as the direction ofrotation for setting the packer, without the necessity of applying reciprocating movement to the running-in string.

A further object of this invention is to provide a well packer having a mandril provided with tubular body having conventional drag springs thereon and a plurality of swingably mounted serrated dogs depending therefrom, movable into and out of anchoring engagement with the well casing.

One of the most aggravating problems experienced in the neld of oil and gas drilling is that of being unable to retrieve well packers from within the casing after gas or oil has been taken from the well because of iiuid obstruction below the tool. Such obstruction often makes it impossible to release the tool from the set position and thereby presenting diicult retrieving operations. It is, therefore, one of the most important objects of this invention to provide a well packer that may easily be retrieved from the well casing irrespective of any fluid'obstruction that may be present after fluid has been pumped therethrough,

Many other objects will be made clear or become apparent throughout the course of the following specication, reference being had tothe accompanying drawings, wherein:

Fig. 1 is a side elevational view of a well packer made in accordance with my present invention, showing the same disposed within a well casing and the expander assembly, as well as the packing element, in the inoperative position.

Fig. 2 is a side elevational view thereof showing the expander assembly and thev packing element in the operative position, parts Abeing broken away to reveal details Aof construction.

Fig. 3 is a side elevational view showing the same in another inoperative position, parts being broken away for clearness. f

Fig.y 4 is a cross sectional view taken von line IV-IV of Fig. 2 looking in the direction of the arrows. A t

Fig. 5 is a cross sectional View taken on line V-V of Fig. 2,

Fig. 6 is a cross sectional view taken on line VI-VI of Fig. 3 looking in the direction of the arrows.

Fig. 7 is an expanded perspective View showing parts of the actuating means for the expander assembly; and .Y

Fig. 8 is a cross sectional View taken on line VIII- VIII of Fig. 1, looking in the direction of the arrows. In the drawings, the numeral I!) designates a section of a well casing within which is disposed the packer forming the subject matter of my present invention. The packer'includes a tubular mandril of conventional character broadly designated by the numeral I2 and attached to one endof a running-in string I4 throughthe medium of acoupling I5. Y Mandril I2 has external ribs I8 formed thereon intermediate its ends for purposes more fully hereinafter described and aholding ring or stop 20 secured thereto near its normallyvlowermost end through the medium of a set screw 22. The oppositeflend of mandril I2 carries a tubular body 24 having

upper andvlower rings

26 and 28 respectively, integral therewith and of conventional character for receiving a number o f spaced'drag springs 3Q in theusual manner.' These -drag springsgll serve to holdj the packer withinthe casing jID by tightY engagement with the inner walls thereoipwhile the packer isset and freleased in the manner hereinafter morey fully descri bedf.,yj f Y Body 24 has alongitudinal b ore 32 therethrough for slidably receiving the mandrilI2 as well as to permit-rotational movement of mandrl I2 3 within body 24. The extent of sliding reciprocation within body 24, as well as rotation of mandril I2, is limited by a laterally extending pin 34 on mandril I2 projecting into a Z-slot formed in body 24,

This slot includes a longitudinal leg 36 and a pair of horizontally extending

legs

38 and 48 respectively. The normally lowermost end of the body 24 is formed to present a pair of spaced apart

flanges

42 and 44 to receive a continuous ring 46 therebetween.

Ring 44 has a number of notches 48 formed therein to receive a like number of supporting arms 50 for dogs 52. These arms 50 are perforated at their uppermost ends for receiving the ring 45 to the end that the arms 50 and the dogs 52 pivotally secured thereto as at 54 are rendered swingable. Suitable serrations 55 are formed on the outermost edges of each of the dogs 52'. The entire expander assembly, therefore, including the dogs 52, is mounted upon the body 24 and rendered immovable with respect to rotation and longitudinal movement within the casing I8 when the springs 38 are in tight engagement therewith.

` A wedge member 56 formed as clearly illustrated in Fig. 7 of the drawings, is tapered to a smaller outside diameter at the normally uppermost end thereof and has a number of longitudinal grooves 58 formed therein on its outermost surface. This tapered wedge member 56 has a continuous longitudinal, substantially central bore therethrough, the uppermost end whereof is provided with internal ribs 68 adapted to engage within slots between the ribs I8 of mandril I2 to provide a slidable spline construction.

Y Member 55 is slidably mounted upon the mandril I2 below the ring 44 of body 24 and adjacent the ribs I8 of mandril I2, as clearly illustrated in Fig. 3.

A pair of

sleeves

62 and 64 also circumscribe the mandril I2 and this mandril I2 is freely slid- .ableand rotatable within the sleeve 64 as illustrated in Fig. 2. Internal and external left hand threads are formed in the

sleeves

62 and 64 respectively to the end that the same may be interconnected in the manner illustrated in Fig. 3. Before such interconnection is made between

sleeves

62 and 64, the wedge member 56 is inserted into the sleeve 62 for free sliding movement therein and above the uppermost end ofthe sleeve 64. Obviously,'the inner surface of the sleeve 62 is tapered to conform to the contour of wedge member 55 and a number of notches 66 are formed in this sleeve 82 extending downwardly from its normally uppermost end.

`A packing ring 68 made from compressible material such as rubber or a composition of fabric and'rubber is disposed immediately below the sleeve 64 in circumscribing relation to the mandril I2 and this mandril is also free to slide within the centralv bore through ring 68.

Anumber of pins 12 are embedded'within this packing element 68 and extend upwardly into thesleeve 64 as illustrated in Fig. 2 to receive nuts 14, which nuts 14 are in turn disposed within cut out portions 18 in the sleeve 64.

A- ring 18 circumscribes the mandrilv I2 and is disposed between the holdingvring 28 and the packing element 68. The uppermost end of the central-bore 80 through the holding ring 20 is tapered outwardly as at 82 to receive inclined edges 84 of ring 18 as illustrated in Fig. 2. 'I'he opposite end of this ring 18 is also inclined as at 88 tothe end that when packing element 68 is compressed in the manner shown in Fig. 2, a

4 lip 88 will be formed by the element 88, wedged between the casing I Il and the ring 18.

Operation When the well packer is first lowered into the casing I8 through the medium of the running-in string, the component parts thereof are assembled as illustrated in Fig. 1 of the drawings.

The body 24 and the mandril I2 are rotated and shifted relative to each other to dispose pin 34 within the leg 40 of the slot formed in body .24 with the pin 34 at the end of leg 40 farthest from longitudinal leg 35. The dogs 52 are disposed within the notches 68 of sleeve 62 and bear against the Wedge 56 between the longitudinal grooves 58 therein. When the pin 34 is so disposed,the wedge 55 is in a position with respect to dogs 52 to render the latter freely swingable and out of engagement with the walls of casing I8. In other words, the uppermost end of the wedge member 56 is near or below the lowermost ends of the'dogs 52 and in this position, wedge member 56 has its internal ribs 68 out of engagement with the slots between ribs I8 of mandri1 I2.

After the operator has positioned the packer at the desired location within the casing I0, the running-in string I4 and the mandril I2 connected thereto are rotated to move the pin 34 into the leg 36 of the slot formed in body-24. The mandril I2 is then pulled upwardly to move the pin 34 to thevuppermost end of leg 36 as illustrated in Fig. 2. This action causes ring 20 to move ring 18member 68, sleeve 64, sleeve 82 and wedge 56 upwardly within the casing I0 toward the body 2.4. Wedge 56 will thereby vmove the dogs'52 into tight anchoring engagement within the interior of casing I0 as illustrated in Fig. 2. At the same time, the packing element E8 is compressed between ring 18 and sleeve 64 to completely seal off the lowermost end of the casing, I0 and the lip 88 is automatically formed because of the construction of the ring 18. A positive seal is thereby formed by the wedging action of the tapered portion 86' of ring 18 upon the packing I6 by pressing the lsame tightly against the Walls of casing I8.

VIt is'notable ythat the formation of ring, 18 as at iand the tapered portion 82 of the ring20 permits rotation of the mandril I2 without undue friction or distortion ofthe packing element 68;

When it is desired to reset the packer'or remove thesame from within casing I8, the procedure just described is reversed by first moving mandril I2 downwardly with respect to body 24 and then rotating the same to move the pin 34 into the leg 46 of the slot formed in-body 24. It is to be noted that when the assembly is inthe condition illustrated in Fig. 1, rotation of f the mandril I2 has no effect upon the wedge member 56 since the ribs I8 of mandril I2 are out'of engagement with the ribs 58 of wedge member 5B.

oftentimes it is impossible after runningiiuid through the mandril I2 and the running-in string 'I4 to lower mandril I2 and release the tool because -of fluid obstruction therebelow. Ordinarily, when such condition exists. it is impossible to retrieve such tools. In-the packer just described however, when such fluid obstruction exists, the operator simply rotates the running-in-string I4 and the mandril I2 to move the-pinr34 toward the closed end of leg 38 of the slot. Such rotation causes the wedge member V56 to turn within the sleeve 62 because of the interengagement at spline I868. bringing the grooves 58 of wedge member V66 into vregister with the notches 86.01.'

sleeve 62. This permits the dogs 52 to move into the grooves 58 and out of anchoring engagement with casing l D, whereupon the tool may easily be removed from the casing Il). It is notable that wedge member 56 will freely rotate as above described irrespective of the fact that the dogs 52 engage the same because of the provision of a number of roller bearings 99 on that portion of wedge member 56 between the grooves 58 thereof. Obviously, with dogs 52 released, the mandril i2 may be actuated to move the packing member 68 to the retracted position illustrated in Fig. 1.

Having thus described the invention, what is claimed as new and desired to be secured by Letters Patent is:

1. In a well tool, a tubular body having yieldable means adapted to frictionally engage the interior of a well casing to hold the body in a predetermined position relative to the casing when the tool is inserted thereinto; an elongated, vertical mandril extending through the body and rotatable therein, said mandril being shiftable on its vertical axis relative to the body; means including a substantially Z-shaped slot formed in the body having a vertical leg, a lower, horizontal leg, and an upper horizontal leg, and a pin on the mandril extending through the slot for limiting the extent of rotation and shifting movement of the mandril relative to the body; a stop below the body onthe mandril; a frusto-conical, wedge member normally rotatable on the mandril and slidable vertically therealong between the stop and one end of the body; slidable spline structure on the mandril and the wedge member and interengageable to interlock the mandril and the member for rotation together; compressible means rotatably mounted on the mandril between the member and the stop for normally holding the member biased toward said one end of the body with said structure disengaged when said compressible means is in an uncompressed condition; and a plurality of dogs swingably secured to the body and depending from said one end thereof in engagement with the outermost frustoconical surface on the Wedge member and swingable by said surface against the casing into wedging position when the mandril is rotated to move said pin from the lower horizontal leg of the slot into the vertical leg and thereupon shifted in an upward direction relative to the body to thereby compress said compressible meansv and interlock the spline structure, said surface of the member having a plurality of longitudinally extending, spaced grooves therein, one for each dog respectively and disposed to receive the dogs out of anchoring engagement with the casing upon rotation of the mandril to move the pin from the vertical leg of the slot into the upper horizontal leg of the slot and to thereby rotate the member when said structure is interlocked.

2. In a well tool as set forth in claim 1 wherein is provided a sleeve mounted on the compressible means between the compressible means andsaid one end of the body' and surrounding the mandril, said sleeve having a notch for each dog respectively whereby to hold the sleeve and the compressible means against rotation relative to the body, said member being within the sleeve.

3. In a well tool as set forth in claim 1 wherein said compressible means comprises a packing ring adapted for sealing engagement with the casing when compressed.

JERRY D. WRITTEN.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 2,248,211 Young July 8, 1941 2,358,400 Baker Jan. 30, 1945