US3525393A - Packer - Google Patents

Description

Aug. 25, 19 70 IJ cosas ET AL PACKER 2 Sheets-Sheet l Filed Nov. 18, 1968 INVENTORS. A. K. KLINE J. H. cosas TTORNEYS J. H. COBBS ET AL Aug. 25,' 1970 PACKER 2 Sheets-Sheet 2 Filed Nov. 18, 1968 /NVENTORS A. K. KLINE J. H. COBBS %M ;Mam

AT TORNEYS United States Patent O U.S. Cl. 166-187 7 Claims ABSTRACT OF THE DISCLOSURE This invention relates to a packer for use in an oil well bore hole.

More particularly, the invention relates to a packer including a tube member carried into a bore hole by a length of casing, a cylinder member supported to the eX- terior of the tube forming an annular cylindrical cavty, a tubular packer member surrounding the tube below the cavty, a piston member in the cylindrical cavty having communication with the interior of the tube through an opening, the piston member being actuatable by fluid pressure within the cavty to force downwardly against the packer member and thereby expand the packer member outwardly against the bore hole and a valve interior of the tube normally covering the opening communicating with the cylinder cavty and slidable to expose the cylinder cavty when it is dcsired to actuate the packer element.

BACKGROUND AND SUMMARY OF THE INVENTION The use of packers in the oil industry is well known. Packers are used when it is desired to seal the eXterior of a casing to the bore hole in which it is positioned. Packers may likewise be utilized to seal the exterior of a string of tubing to the interior of a string of casing in which the tubing is Situated.

Packers of the known type customarily involve rather complex mechanisms and devices. Due to such complexities, packers of the present type are relatvely expensive, especially those intended for use to seal large diameter bore holes. The packer of this invention is primarily applicable to seal a casing extending into a storage cavty or a gas storage well. The invention provides a hydraulic packer which can be actuated at the conclusion of the cementing of a casing string in a bore hole. The packer provides a seal which serves to prevent flow of fluid from a storage cavern or gas well passing through the micro annulus which may exist between the casing and the cement exterior of the casing and in general is highly useful to prevent fluid or gas leakage through the cement surrounding a casing cemented in a bore hole.

It is therefore a primary object of this invention to provide an improved packer for use in scaling a casing to the interior of a bore hole. A more particular object of this invention is the provision of a packer which is not set until the casing which the packer is attached to has been cemented in place in the bore hole and in which no cementng ports are opened to the annulus after the packer is set.

Another particular object of the invention is the provision of a packer for sealing a casing to a bore hole having improved elfectiveness in maintaining a positive seal with the bore hole.

These and other objects of the invention will be better understood with reference to the following description and Claims.

DESCRIPTION OF THE VIEWS FIG. 1 is a cross-sectional view of a packer of this invention shown in the collapsed or non-actuated position.

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FIG. 2 is a cross-sectional View taken along the line 2-2 of FIG. 1.

FIG. 3 is a cross-sectional View taken along the line 3-3 of FIG. 1.

FIG. 4 is a cross-sectional View of the packer aflixed to the lower end of a length of casing in a bore hole and showing the relationship of parts of the packer during the initial stages of setting the packer.

FIG. 5 is a cross-sectional view as shown in FIG. 4 but showing the packer in an intermediate position.

FIG. 6 is a fragmentary cross-sectional view as shown in FIGS. 4 and S, but showing one embodiment utilizing a highly flexible packer member in the fully set position.

DETAILED DESCRIPTION Referring now to the drawings and first to FIGS. 1, 2. and 3, the packer of of this invention is shown. The packer is basically assembled about a tube member 10 which, in the illustrated embodiment, is threaded on the upper exterior end. A retaining collar 12 having internal threads on the lower interior portion is threadably received on the upper end of the tubing member 10. Retaining collar 12 is adapted to be alfixed to the lower end of a casing string, such as by welding.

In the tube member 10 are small diameter openings 14. While only one of such openings 14 is required according to the function of the invention, in the practical embodiment a plurality of openings 14 are arranged in a common plane perpendicular to the longitudinal axis of the tube member 10 spaced evenly apart from each other around the total periphery of the tube member (see FIG. 2). Affixed to the exterior of the tube member 10 is a cylinder member 16, the cylinder member having an internal cylindrcal surface 16A of greater interior diameter than the exterior diameter of the tube member 10. The cylinder member 16 is supported coaxially of the tube member 10 and is closed to the tube member by an upper flange portion 1 6B. The flange portion 16B includes grooves 18 adapted to receive gaskets therein to insure leakproof sealing of the member against tube 10. The upper flange portion 16B preferably engages retaining collar 12 to prohibit upward movement of the flange portion relative to the tube member 10 during the setting of the packer which will be described subsequently.

The cylinder member .16 provides an annular cylinder cavty 20. Positioned within the cylinder cavty 20 is an annular piston member 22. The piston member 22 is sealed against the exterior surface 10A of the tube member and also against the interior surface 16A of the cylinder member. Gasket grooves 24 are provided in both the interior and exterior surface of the piston member 22 to insure scaling of the piston member to the sides of the cylindrical cavty 20.

Atfixed to the lower portion of piston member 22' and extending downwardly is a push sleeve 26 having an exterior diameter less than the interior diameter of the cylndrical surface 16A of the cylinder member and of an interior diameter greater than the exterior diameter 10A of the tube member.

Affixed to the exteror of the tube 10A is a tubular packer member 28 formed of resilient material, such as rubber. A packer retainer ring 30 in secured to the exterior of the tube member 10 and encompasses the lower end portion of the packer member 28. The packer retaining ring secures the lower end of the packer member 28 immovable relative to the tube member 10.

Slidably positioried on the exterior of the tube member 10 below the cylinder member 16 is an annular upper packer follower ring 32 which encompasses the upper end portion of the packer member. Packer member 28 is not bonded or otherwise secured to the exterior of the tubing &525393 10 but is free to expand outwardly in a manner to be described subsequently.

Received within the cylinder cavity 20 is an expandable valve sleeve 34. The valve sleeve 34 is of a resilient material and covers openings 14. The sleeve functions in the nature of a check valve, that is, it expands to permit fluid to flow under pressure from within tube member 10 through openings 14 and into the cylinder cavity 20 above the piston member 22. However, if the fluid pressure within tube member 10 is reduced below that in the fluid cavity 20, sleeve 34 functioning as a check valve closes over openings 14 and prohibits flow of fluid from the cavity 20. Piston 22 is configured to include a circumferential notch 36 on its upper interior diameter which receives the sleeve 34 as the piston is in its uppermost position, as shown in FIG. 1.

Slidably positioned within the tube member 10 is a valve sleeve generally indicated by the numeral 38. The valve sleeve includes a cylindrical portion 38A which sealably engages the interior of tube 10, and a vertical upper plate 38B which is afiixed to the sleeve portion 38A at the upper end. The plate portion 38A has a large diameter axial opening 40 theren. When the packer is affixed to the lower end of the tube string to be inserted into a bore hole, valve member 38 is positioned as shown in FIG. 1, that is, to fully cover openings 14 and thereby prevent fluid within the tubing from passing through openings 14. Large diameter opening 40 permits free fluid flow through the tube members 10 so that, with the packer attached to the lower end of the length of casing, fluid such as cement slurry or the like may be pumped downwardly without obstruction to pass through the opening 40 in tube member 10.

OPERATION FIGS. 4 and 5 disclose the method of operation of the packer of this invention. When it is determined to set the packer so as to seal ofl? the annulus between the exterior of the casing 42 to which the packer is supported and the interior 44 of the bore hole in which the packer is positioned, a plug 46 is inserted into the casing at the surface. The plug passes downwardly until it engages the 'valve member 38 wherein flow of fluid through the valve causes the plug 46 to cover the opening 40. With plug 46 in position over opening 40 fluid can no longer flow past the valve member 38 and the pressure differential soon builds up across the valve member and slidably moves the valve member downwardly as shown in FIGS. 4 and 5. While n the drawings the valve member 38 is shown to be displaced only a slight distance downwardly, in practice it will be moved downwardly until some obstruction is encountered.

When the valve member 38 moves downwardly by the effect of pressure in the casing, openings 14 are exposed. Fluid can then flow through openings 14 under pressure, expanding the valve sleeve 34 outwardly. This introduces fluid pressure within the cylinder cavity 20 above the piston member 22 forcing piston member 22 and thereby push sleeve 26 and follower ring 32 downwardly. This downward motion of the follower ring 32 causes the packer member 28 to collapse outwardly against the interior of the bore hole.

This invention includes the provision of an enlarged internal diameter notch 44 in the packer member 28. The thickness of the packer member being less at the notch, downward pressure causes the packer member to first bulge in the area containing the notch 44. This causes the elastomeric packer 28 to well out into a cup as the tool is set. As more downward pressure is applied the thicker portions of the packer are expanded outwardly. The provision of the internal circumferential notch 44 causes the packer to be expanded with less force than would be required if the notch 44 were not provided.

As the pressure within the tube member increases and such pressure is communicated through openings 4 14, piston 22 is pushed downwardly with increasing force until the packer is firmly compressed against the interior of borehole 46 along substantially the full length of packer member 28. As shown in FIG. 5, the packer is completely set and fully sealed against the interior of the bore hole.

When pressure is removed from the interior of the tube member 10 there is a tendency for the packer member 28 to push the piston member 22 back upwardly. This is prevented, however, by valve sleeve 34 which closes openings 14. Thus, the sleeve functions in the nature of a check valve freely permitting fluid to enter the cylinder cavity 20 but prohibiting the escape of fluid therefrom. The packer once set remains set even after the pressure of fluid is removed from the interior of the tube mernber 10.

The enlarged internal diameter notch portion 44 in the packer member 28 is preferably of a length less than one half of the total length of the packer member as such lengths are measured paralleled the packaer member tubular axis.

FIG. 6 shows the packer in fully set position in which a highly flexible packer member 28` is utilized. In this embodiment the packer member is caused to form, at each end, annular folded portions 28A. These folded portions 28A insure positive sealing of the packer member against the bore hole 46. In addition, after the packer member has been formed into the configuration as shown in FIG. 6 it tends to remain in such sealing condition even though the force of the push sleeve is removed. Thus the packer remains in the set condition after pressure within tube member 10 is removed, even if valve sleeve 34 fails to hold against flow of fluid out of cylinder cavity 20.

While the invention has been described with a certain degree of particularity, it is manifest that many changes may be made in the details of Construction and the arrangement of components without departing from the spirit and scope of this disclosure. It is understood that this invention is not to be limited to the abstract herein, nor the Summary, nor the detailed description for purposes of exemplifying one em 'bodiment of the invention, but the invention is to be limited only by the scope of the appended claim or claims, including the full range of equivalency to which each element is entitled.

What is claimed:

1. A packer for use in an oil well bore hole comprisng:

a tube member adaptable to be carried into a well bore hole by a string of casing, the tube member having at least one opening in the tube wall;

a cylinder member of internal diameter greater than the external diameter of said tube member supported coaxially exteriorly of said tube member and being closed to said tube member at the upper end forming a downwardly extending annular cylinder cavity, said opening in said tube member communicating with the upper end of said annular cylinder cavity;

a tubular packer member of resilient material coaxially received about said tube member and below said cylinder member;

a packer retainer ring affixed to the exterior of said tube member and encompassing the lower end portion of said packer member securing the lower end portion of said packer member immovable relative to said tube member;

an upper *packer follower ring slidably received on the exterior of said tube member below said cylinder member, said follower ring encompassing the upper end portion of said packer member;

an annular piston member in said cylinder cavity slidably and sealably engaging the exterior of said tube member and the interior of said cylinder member, said piston member being downwardly displaceable &525393 by the pressure of fluid passing into said cylinder cavity through said opening in the tu be member, said piston member engagng said upper packer follower ring whereby downward movement of said piston member expands said packer member outwardly in increased diameter; and

means normally closing said opening in said tube wall and actuatable to expose said opening to fluid pressure within said tube member when it is required to expand said packer element.

2. A packer for use in an oil well bore hole according to claim 1 wherein said means normally closing said opening in said tube wall includes a valve sleeve slidably and sealably positioned in the interior of said tube member and normally overlying said opening.

3. A packer for use in an oil well bore hole according to claim 2 wherein said valve sleeve includes a horizontal plate portion having an axial relatively large diameter flow passageway therein normally permitting unobstructed flow of fluid through said valve sleeve, said flow pas-- sage being closa'ble by a wiper plug or the like, whereby said valve sleeve is moved downwardly in said tube member by fluid pressure exposing said openings.

4. A packer for use in an oil well bore hole according to claim 1 wherein said annular piston member includes a downwardly extending push sleeve of internal diameter larger than the external diameter of said tube member and of external diameter less than the internal diameter of said cylinder member, the lower end of said push sleeve engaging said upper packer follower ring.

5. A packer for use in an oil well bore hole according to claim 1 including a check valve means closing said opening in said tube member, said check valve means permitting fluid flow from the interior of said tube member into said cylinder cavity and preventing flow of fluid from said cylinder cavity.

6. A packer for use in an oil well bore hole according to claim 5 wherein said check valve means includes a sleeve of reslient material positioned on the exterior of said tn'be member and within said cylinder cavity normally covering said openings in said tube member.

7. A packer for se in an oil well bore hole according to claim 1 wherein said tubular packer member is defined in part by an integral increased internal diameter portion at the lower end thereof, the length of said increased internal diameter portion being less than one half the total length of said packer member as such lengths are measured parallel the packer member tubular axis.

References Cited UNITED STATES PATENTS 1,924,425 8/ 1933 Wckersham et al. 166-194 X 2,029,380 2/1936 Manning i 166-194 X 2,196,658 4/1940' Burt 166-194 X 3,053,322 9/1962 Kline 166-187 X 3,059,699` 10/1962 Brown 166-187 DAVID H. BROWN, Primary Exam'ner U.S. CI. X.R. 166-194

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