US 2734582 A
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Description (OCR text may contain errors)
Original Filed May 3, 1952 2 Sheets-Sheet l QFHQI' INVENTOR, E0698 ((1. SHEA/Ell Feb. 14, 1956 E. WxBAGNELL 2,734,582
PACKER CONSTRUCTION Original Filed May 5, 1952 2 Sheets-Sheet 2 i I 49 506 39 a/ l s e A fizz BY 5 m (M4 $440144, flk EG.5
PACKER CONSTRUCTION Edgar W. Bagnell, Glendale, Calif., assignor to Johnston Testers, Inc., Houston, Tex., a corporation of Delaware 4 Claims. (Cl. 166-187) This invention relates to a packer for oil well tools, and the present application is co-pending with and forms a division of my prior application entitled, Wire Line Tester, Serial No. 285,981, filed May 3, 1952.
It is a principal object of the present invention to provide a packer having an expansible packer sleeve and contrivances at the ends of the packer sleeve to limit end bulging of said sleeve; to provide such a packer equipped with a rigid core for partially controlling the manner of expansion thereof; and to provide such a packer adapted to be expanded hydraulically.
It is another object of the present invention to provide a tool equipped with the above-described packer and adapted to be supported from a string of drill pipe or a wire line.
Various other objects of the present invention will be apparent from the following description taken in connection with the accompanying drawings, in which:
Fig. 1 discloses a portion of an oil well tool having a pair of packers embodying the concepts of the present invention carried thereby.
Fig. 2 is an enlarged vertical sectional view of the upper packer disclosed in Fig. 1, showing the packer in its collapsed position.
Fig. 3 is a view similar to Fig. 2 but showing the packer after it has been expanded.
Fig. 4 is a horizontal sectional view taken along line 4-4 of Fig. 2.
Fig. 5 is a horizontal sectional view taken along line 5-5 of Fig. 3.
Fig. 6 is a still further enlarged fragmentary sectional view of a single flexible end shell, more particularly showing the construction of such shell.
Referring to the accompanying drawings wherein similar reference characters designate similar parts throughout, Fig. 1 shows, fragmentarily, a tool generally entitled 11, the detailed construction of which is not of importance to the present invention. Actually, the portion of the tool disclosed is a somewhat schematic illustration of a portion of my Wire Line Tester disclosed in my copending application above identified. A number of the parts of the tool disclosed in Fig. 1 have been simplfied in an effort to emphasize the novel construction of the packer of the present invention.
The portion of the tool disclosed in Fig. 1 includes a top packer head 13 connected to a central packer head 15 by a tubular mandrel 17, the central packer head being connected to a lower packer head 19 by a lower tubular mandrel 21. The upper packer head is connected by a sub or pipe section 23 to the upper part of the tool, while the lower packer head has suspended therefrom a pipe section 25.
Surrounding mandrel 17 is a packer generally entitled 27 and surrounding mandrel 21 is a packer generally entitled 29 identical in construction to packer 27. Only the upper packer 27 will be described in detail.
Packer 27 includes an expansible elastomer sleeve 31 containing a rigid annular core 3 mounted by frictional nited States Patent 0 engagement on the exterior of the mandrel 17. Sleeve 31 tightly grips the exterior of mandrel 17 by means of annular sharp edged lips 35 formed on said sleeve and extending toward one another. Lips 35 prevent the escape of hydraulic fluid between the ends of the packer sleeve and mandrel 17. Core 33 is interiorly fluted to allow fluid to pass between the core interior and mandrel 17 to the ends of the core and into the spaces 39 formed in the end of sleeve 31.
Sleeve 31 is medially thickened, as indicated at 60, to provide thin ends indicated at 61 which first expand for a purpose to be presently described.
At each end of sleeve 31 and surrounding mandrel 17 are a plurality of annular superimposed or nested expandable shells 41 embracing said sleeve ends and normally assuming collapsed position as shown in Fig. 2. These shells are formed of a material of a less expansible nature than that of which the sleeve 31 is formed, and preferably are formed of an elastomer impregnated fabric. As shown in Fig. 6, each shell preferably includes several elastomer impregnated fabric pieces 43 of different diameters bonded together to provide a thick inner portion for the shell and a thin outer portion.
The opposed faces of the upper and central packer heads are formed to converge in directions away from each other to provide backing faces 47 and 49 for limiting expansion of shells 41. Each shell 41 has an expanded diameter greater than that of the well bore into which the tool is lowered for a purpose which will presently appear.
As is apparent from Fig. 2, when the packer is in its collapsed position the shells 41 at each end of the packer sleeve curve away from the associated faces 47 and 49 of the upper and lower packer heads, therefore allowing the shells to be expanded toward the walls of the well bore for a considerable degree before fully encountering backing faces 47 and 49.
For expanding packers 27 and 29, fluid within mandrels 17 and 21 is forced by any suitable means through ports 51 formed in the mandrels into the interiors of the packer sleeves causing them to expand from the position shown in Fig. 2 to the position shown in Fig. 3 away from their cores.
During the expansion of the packer sleeves, the thin ,ends thereof expand first and bulge in an axial direction to cause expansion of expandable shells 41 so that the outer radial portions of the shells are forced axially away from one another, which movement obviously causes a radial expansion of said shells into engagement with the walls of the well bore as clearly shown in Fig. 3, and also into full engagement with backing faces 47 and 49, which action limits further axial movement of the major portions of said shells. Since the expanded diameter of each shell is greater than the diameter of the Well bore, it is apparent that the outer margins of the shells are packed against the walls of the well bore and prevent further end bulging of the elastomer packer sleeves. The collapsed and expanded positions of the packer sleeves are shown in Figs. 4 and 5, respectively.
The tubes 53 and 55, shown in Fig. 1 and partially in Figs. 2 and 3, form parts of the particular tool disclosed in my co-pending application previously identified and are included herein merely to enable a comparison of the structure disclosed herein with that disclosed in my prior co-pending application, and perform no function in the present invention. Mandrels 17 and 21 have the interiors thereof communicating with one another through a tubular member 53, the internal construction of which is not particularly important to the present invention.
By the present invention the use of a relatively thin wall expansible packer sleeve has been made practicable because of the provision of a rigid annular core contained within the sleeve and flexible end shells disposed exteriorly and at the ends of the packer sleeve, said core functioning to sustain the general form of the sleeve, and said end shells functioning to prevent rupture of said sleeve. This sleeve design obviously eifects a saving of rubber. Furthermore, .a thin wall packer sleeve can be more readily expanded than a thick wall sleeve, and can be expanded to av greater degreethan. a thick wall sleeve without danger of rupture. Also, whenrunning in a well, the annular core prevents the hydrostatic head in the well from collapsing the packer sleeve, which collapse would build up the pressure of the hydraulic fluid within the tool and cause premature opening of the test valve employed in a tester such as disclosed in my co-pending application previously identified. The core also partially controls the manner of expansion of the packer sleeve to prevent uncontrolled and erratic expansion thereof. It is apparent that the above advantageous operating and design features lengthen the life of a packer sleeve, enabling it to beused .over and over again.
Although the invention has been described in connection with expanding ,the packers into engagement with the walls of a wellbore, it is apparent that the packers are equally adaptable 'for expansion into engagement with the walls of a casing, pipe or other tubular member.
While I have shown the preferred form of my invention, it is to be understood that various changes may be made in its construction by those skilled in the art without departing from the spirit of the invention as defined in the appended claims.
. Havingthus described my invention, what I claim and desire to secure by"Letters'Patent is:
l. A device of the class described, comprising a mandrel, an expansible packer sleeve on the mandrel, a rigid annular core mounted on the mandrel within the sleeve, the ends of said core being spaced interiorly from the ends of said sleeve, a lateral port in said mandrel adjaeent the mid-portion of said core, longitudinal passageways between said core and said mandrel connecting said port with the ends of said core, and well bore wall-engaging means on the mandrel external of and in engagement with one end of the packer sleeve normally contracted into position spacedfrom the walls of a well bore but being expanded upon expansion of the packer sleeve to engage-the walls of the well here and limit end expansion of said one end of said sleeve, said port and passageways constituting means for conducting fluid under pressure to the interior of the annular core and around the ends thereof into the sleeve to-expand the same.
2. A device of the .class described comprising a mandrel, an expansible packer sleeve on the mandrel, expansible means engaging one end of the packer sleeve for limiting end movement of said one end of said packer sleeve, a rigid annular core disposed on said mandrel within the packer sleeve for preventing collapse of the sleeve, longitudinal grooves formed on the interior of said core having ends communicating with said sleeve, and means defining a port forconducting fluid under pressure from the mandrelinto said grooves for discharge through said grooves in'said core and around the ends thereof into the ends of the sleeve to expand the same away from said core into engagement with the wall of the well bore.
3. A device of the class described comprising a mandrel,. an expansible packer sleeve on the mandrel, a plurality of nesting concave elastomer impregnated fabric expansible shells on the mandrel external of and in engagement with one end of the sleeve, a plurality of nesting concave elastomer impregnated fabric expansible shells on the mandrel external of and in engagement with the other end of the sleeve,.expansible upon and by expansion. of said sleeve to engage the Walls of a well bore and'limit end expansion of said sleeve, there being a pair of rigid enlargements on the mandrel, one of said enlargements at the side of-one set of the shells remote from said sleevesan'd the other at'the side of the other set of shells remote from said sleeve for'limiting expansion of the shells, said enlargements having opposed frustoconical faces, a rigid annular core mounted onthe man- 'drel within the sleeve, and means for conducting fiuid pressure through and around the ends of said core to the interior of the sleeve to expand the sleeve into engagement with the walls of a well bore.
4. -A device of the class described comprising a mandrel,.an expansible packer sleeve on the mandrel, means for expanding, said sleeve, and a plurality of nesting concave elastomer impregnated 'fabric expansible shells of different diametersion the mandrel external of and in engagement with one end of the sleeve expansible upon and'by expansion of said sleeve to engage the walls of a well bore and ,limit end expansion of said sleeve, there being a rigid enlargement on the mandrel at the side of the shells remote from said sleeve'for limiting expansion of the shells.
References Cited in the file of this patent M we