(12) United States Patent
`Frazier
`
`(10) Patent N0.:
`(45) Date of Patent:
`
`US 6,796,376 B2
`Sep. 28, 2004
`
`US006796376B2
`
`(54) COMPOSITE BRIDGE PLUG SYSTEM
`
`Inventor: Warren I4I Frazier,
`RObStOWn TX (Us) 78380
`’
`
`73,
`
`5,701,959 A * 12/1997 Hushbeck et a1. ........ .. 166/387
`5,819,846 A * 10/1998 Bolt, Jr. .............. ..
`166/123
`6,167,963 B1 * 1/2001 McMahan CI 8.1.
`166/179
`6,220,349 B1 * 4/2001 Vargus et al. ....... ..
`166/138
`6,491,108 B1 * 12/2002 Slup etal. ................ .. 166/387
`
`( * ) Notice:
`
`
`
`Subject to any disclaimer, the term of patent is extended or adjusted under 35
`
`*
`
`~t d b
`
`-
`
`*
`
`Zimmerman Ct 8.1. . . . . . ..
`
`U.S.C. 154(b) by 32 days.
`
`(21) APPL N05 10/189,887
`(22) Filed:
`JuL 2’ 2002
`
`C1 6
`y exammer
`Primary Examiner—David Bagnell
`Assistant Examiner—Shane Bomar
`(74) Attorney, Agent, or Firm—G. Turner Moller
`
`(65)
`
`Prior Publication Data
`
`(57)
`
`ABSTRACT
`
`Us 2004/0003928 A1 Jam 8’ 2004
`7
`(51) Int. Cl. ........................ .. E21B 23/00; E21B 33/12
`
`A composite bridge plug system for containing a Well bore
`With reduced drill up time. The composite bridge plug
`System includes an elongate mandrel, a head member
`
`U-S- Cl- . . . . . . . . . . . . . . . . . . . . . ..
`
`attached to a lower portion of the mandrel, an upper Collar
`
`166/ 138; 166/387
`(58) Field of Search ............................... .. 166/387, 376,
`166/118, 184, 217, 138, 140, 123, 127
`_
`References Clted
`U'S' PATENT DOCUMENTS
`
`(56)
`
`positioned about an upper portion of the mandrel, and a
`plurality of gripping members positioned about the mandrel.
`The gripping members are expandable outWardly When the
`mandrel is pulled upWardly With an engaging tube prevent
`ing the upWard movement of the upper collar thereby
`compressing the gripping members. The upper portion of the
`mandrel includes a shear portion that is breakable by pulling
`upWardly upon the mandrel. An engaging portion surrounds
`the shear portion adjacent to the upper collar that is engage
`able With a loWer slot Within a head member of a higher
`bridge plug thereby preventing rotation of the higher bridge
`plug dunng dnlhng thereof‘
`
`-
`
`-
`
`-
`
`4 Claims, 9 Drawing Sheets
`
`24
`
`22
`4O
`'50
`
`540
`586
`
`5810
`
`54b
`
`’ g‘
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`
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`
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`
`26
`56a
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`
`52k)
`
`30
`
`3,298,437 A * 1/1967 Conrad ...................... .. 166/63
`3,306,362 A * 2/1967 Ufbanosky
`277/339
`4J151J875 A : 5/1979 Sullaway - - - - - - - -
`- - - ~~ 166/126
`2 *
`et a1‘
`5,318,131 A * 6/1994 Baker ................ .. 166/382
`5,390,737 A * 2/1995 Jacobi et al.
`166/184
`5,540,279 A * 7/1996 Branch et a1. ............ .. 166/118
`
`ya . . . . . . . . . .
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`. . . ..
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`,
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`,
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`MEGCO Ex. 1005
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`

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`U.S. Patent
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`Sep. 28,2004
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`Sheet 1 0f 9
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`US 6,796,376 B2
`
`FIG 1
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`MEGCO Ex. 1005
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`

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`U.S. Patent
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`Sep. 28,2004
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`Sheet 2 0f 9
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`US 6,796,376 B2
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`E0
`
`81
`
`-
`
`10K |
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`
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`
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`
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`
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`
`56a
`
`60
`
`1
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`° \ H
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`56k)
`
`5%
`
`38
`
`FIG 2
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`MEGCO Ex. 1005
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`

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`U.S. Patent
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`Sep. 28,2004
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`Sheet 3 0f 9
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`US 6,796,376 B2
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`FIG 3
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`MEGCO Ex. 1005
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`

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`U.S. Patent
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`Sep. 28,2004
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`Sheet 4 0f 9
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`US 6,796,376 B2
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`12
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`Ml
`Ml
`
`l
`
`14
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`70
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`FIG 4
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`MEGCO Ex. 1005
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`

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`U.S. Patent
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`Sep. 28,2004
`
`Sheet 5 0f 9
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`US 6,796,376 B2
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`16
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`18
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`70
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`FIG 5
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`MEGCO Ex. 1005
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`U.S. Patent
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`Sep. 28,2004
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`Sheet 6 6f 9
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`US 6,796,376 B2
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`7
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`32
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`FIG 6
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`MEGCO Ex. 1005
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`U.S. Patent
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`Sep. 28, 2004
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`Sheet 7 of 9
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`US 6,796,376 B2
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`84
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`82
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`FIG 7
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`MEGCO EX. 1005
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`MEGCO Ex. 1005
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`

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`U.S. Patent
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`Se .28 2004
`
`Sheet 8 of9
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`70
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`
`
`
`
`
`
`
`
`
`
`FIG8
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`%E6
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`MEGCO Ex. 1005
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`

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`U.S. Patent
`
`Sep. 28, 2004
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`Sheet 9 of 9
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`US 6,796,376 B2
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`
`MEGCO Ex. 1005
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`

`
`US 6,796,376 B2
`
`1
`COMPOSITE BRIDGE PLUG SYSTEM
`
`CROSS REFERENCE TO RELATED
`APPLICATIONS
`
`Not applicable to this application.
`
`STATEMENT REGARDING FEDERALLY
`SPONSORED RESEARCH OR DEVELOPMENT
`
`Not applicable to this application.
`
`BACKGROUND OF THE INVENTION
`
`1. Field of the Invention
`The present invention relates generally to bridge plugs
`and more speci?cally it relates to a composite bridge plug
`system for containing a Well bore With reduced drill up time.
`2. Description of the Related Art
`Bridge plugs have been in use for years. Conventional
`bridge plugs are comprised of a metallic material Which is
`loWered into a Well bore via a Wire line or steel tube. To set
`the conventional bridge plugs Within the Well bore, the user
`caused slips Within the bridge plug to extend outWardly
`thereby contacting the Well bore Walls and an elastomeric
`packing element to seal to the Well bore by using an
`electronic means or pump force.
`While these devices may be suitable for the particular
`purpose to Which they address, they are not as suitable for
`containing a Well bore With reduced drill up time. Conven
`tional bridge plugs are difficult to remove from a Well bore
`by conventional drilling because they are rotated Within the
`Well bore.
`In these respects, the composite bridge plug system
`according to the present invention substantially departs from
`the conventional concepts and designs of the prior art, and
`in so doing provides an apparatus primarily developed for
`the purpose of containing a Well bore With reduced drill up
`time.
`
`BRIEF SUMMARY OF THE INVENTION
`
`In vieW of the foregoing disadvantages inherent in the
`knoWn types of bridge plugs noW present in the prior art, the
`present invention provides a neW composite bridge plug
`system construction Wherein the same can be utiliZed for
`containing a Well bore With reduced drill up time.
`The general purpose of the present invention, Which Will
`be described subsequently in greater detail, is to provide a
`neW composite bridge plug system that has many of the
`advantages of the bridge plugs mentioned heretofore and
`many novel features that result in a neW composite bridge
`plug system Which is not anticipated, rendered obvious,
`suggested, or even implied by any of the prior art bridge
`plugs, either alone or in any combination thereof.
`To attain this, the present invention generally comprises
`an elongate mandrel, a head member attached to a loWer
`portion of the mandrel, an upper collar positioned about an
`upper portion of the mandrel, and a plurality of gripping
`members positioned about the mandrel. The gripping mem
`bers are expandable outWardly When the mandrel is pulled
`upWardly With an engaging tube preventing the upWard
`movement of the upper collar thereby compressing the
`gripping members. The upper portion of the mandrel
`includes a shear portion that is breakable by pulling
`upWardly upon the mandrel. An engaging portion surrounds
`the shear portion adjacent to the upper collar that is engage
`
`15
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`25
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`35
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`40
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`45
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`55
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`65
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`2
`able With a loWer slot Within a head member of a higher
`bridge plug thereby preventing rotation of the higher bridge
`plug during drilling thereof.
`There has thus been outlined, rather broadly, the more
`important features of the invention in order that the detailed
`description thereof may be better understood, and in order
`that the present contribution to the art may be better appre
`ciated. There are additional features of the invention that
`Will be described hereinafter and that Will form the subject
`matter of the claims appended hereto.
`In this respect, before explaining at least one embodiment
`of the invention in detail, it is to be understood that the
`invention is not limited in its application to the details of
`construction and to the arrangements of the components set
`forth in the folloWing description or illustrated in the draW
`ings. The invention is capable of other embodiments and of
`being practiced and carried out in various Ways. Also, it is
`to be understood that the phraseology and terminology
`employed herein are for the purpose of the description and
`should not be regarded as limiting.
`A primary object of the present invention is to provide a
`composite bridge plug system that Will overcome the short
`comings of the prior art devices.
`A second object is to provide a composite bridge plug
`system for containing a Well bore With reduced drill up time.
`Another object is to provide a composite bridge plug
`system that utiliZes a combination of metal and non-metal
`components for containing a conduit.
`An additional object is to provide a composite bridge plug
`system that may be utiliZed Within oil or gas Well bores.
`A further object is to provide a composite bridge plug
`system that reduces milling or drill out operations of the
`bridge plug.
`Other objects and advantages of the present invention Will
`become obvious to the reader and it is intended that these
`objects and advantages are Within the scope of the present
`invention.
`To the accomplishment of the above and related objects,
`this invention may be embodied in the form illustrated in the
`accompanying draWings, attention being called to the fact,
`hoWever, that the draWings are illustrative only, and that
`changes may be made in the speci?c construction illustrated
`and described Within the scope of the appended claims.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`Various other objects, features and attendant advantages
`of the present invention Will become fully appreciated as the
`same becomes better understood When considered in con
`junction With the accompanying draWings, in Which like
`reference characters designate the same or similar parts
`throughout the several vieWs, and Wherein:
`FIG. 1 is an upper perspective vieW of the present
`invention.
`FIG. 2 is a side vieW of the present invention.
`FIG. 3 is an exploded side vieW of one embodiment of the
`present invention.
`FIG. 4 is a side vieW of the present invention movably
`positioned Within a conduit.
`FIG. 5 is a side vieW of the present invention non
`movably secured Within the conduit.
`FIG. 6 is a side cutaWay vieW of another embodiment of
`the present invention movably positioned Within the conduit.
`FIG. 7 is a side cutaWay vieW of the embodiment of FIG.
`6 non-movably secured Within the conduit.
`
`MEGCO Ex. 1005
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`US 6,796,376 B2
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`3
`FIG. 8 is a magni?ed side cutaway view of the shear
`portion of the mandrel.
`FIG. 9 is a magni?ed side cutaway view of the shear
`portion of the mandrel after being broken.
`
`DETAILED DESCRIPTION OF THE
`INVENTION
`Turning now descriptively to the drawings, in which
`similar reference characters denote similar elements
`throughout the several views, FIGS. 1 through 9 illustrate a
`composite bridge plug system 10, which comprises an
`elongate mandrel 20, a head member 30 attached to a lower
`portion 28 of the mandrel 20, an upper collar 40 positioned
`about an upper portion 24 of the mandrel 20, and a plurality
`of gripping members 52a—b positioned about the mandrel
`20. The gripping members 52a—b are expandable outwardly
`when the mandrel 20 is pulled upwardly with an engaging
`tube 70 preventing the upward movement of the upper collar
`40 thereby compressing the gripping members 52a—b. The
`upper portion 24 of the mandrel 20 includes a shear portion
`22 that is breakable by pulling upwardly upon the mandrel
`20. An engaging portion 21 surrounds the shear portion 22
`adjacent to the upper collar 40 that is engageable with a
`lower slot 32 within a head member 30 of a higher bridge
`plug thereby preventing rotation of the higher bridge plug
`during drilling thereof.
`As shown in FIGS. 6 and 7 of the drawings, the mandrel
`20 is an elongated shaft constructed of a rigid material such
`as but not limited to metal. The mandrel 20 preferably has
`a constant diameter, however the mandrel 20 may have
`varying diameters through the length of the mandrel 20. The
`length of the mandrel 20 may vary depending upon the usage
`required. The mandrel 20 may have various cross sectional
`shapes including hut not limited to circular, square and
`rectangular.
`The mandrel 20 has an upper portion 24 which is pref
`erably threaded for removably being engaged by a coupler
`16 with an installation shaft 18 attached. There are various
`other structures that may be utiliZed for the upper portion 24
`capable of securing the mandrel 20 to a coupler 16.
`As shown in FIGS. 7, 8 and 9 of the drawings, the upper
`portion 24 of the mandrel 20 preferably includes a shear
`portion 22. The shear portion 22 is preferably a narrower
`portion of the mandrel 20 which may be broken after the
`composite bridge plug system 10 has been properly secured
`within the conduit 12. The shear portion 22 may be con
`structed of the same material utiliZed throughout the man
`drel 20 or a weaker material to assist in the breaking of the
`shear portion 22. The shear portion 22 may be broken by a
`pulling and/or rotating force placed upon the mandrel 20 by
`the coupler 16.
`As shown in FIG. 1 of the drawings, an engaging portion
`21 preferably is positioned about the lower end of the
`shearing portion. The engaging portion 21 is shaped to
`receive a lower slot 32 within another head member 30 of
`another composite bridge plug system 10. The engaging
`portion 21 is preferably comprised of a rectangular or square
`structure which may be catchably retained within the lower
`slot 32. The engaging portion 21 has a height suf?cient to
`provide adequate retaining of another composite bridge plug
`system 10 while it is being drilled out.
`The mandrel 20 further has a middle portion 26 that
`extends longitudinally from the upper portion 24 as best
`shown in FIG. 6 of the drawings. Alower portion 28 extends
`from the middle portion 26 and preferably has a threaded
`exterior for threadably receiving a head member 30. The
`
`10
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`head member 30 may also be retained upon the lower
`portion 28 of the mandrel 20 utiliZing various other securing
`mechanisms such as fasteners, welding and the like. The
`head member 30 preferably has a tapered lower end for
`guiding the composite bridge plug system 10 through the
`conduit 12.
`The mandrel 20 and the head member 30 may have a
`longitudinal bore that extends through either partially or
`completely. A check valve or other device may be attached
`within this bore for performing various desired activities
`while the composite bridge plug system 10 is secured within
`the conduit 12.
`As shown in FIGS. 1, 2, and 4—7 of the drawings, a center
`member 60 is positioned about the middle portion 26 of the
`mandrel 20. The upper and lower edges of the center
`member 60 are preferably angled as best shown in FIGS. 5
`through 7 of the drawings. A pair of third members 58a—b
`are preferably positioned about the middle portion 26 of the
`mandrel 20 on opposing sides of the center member 60 as
`best shown in FIG. 7 of the drawings. The third members
`58a—b have outer edges that are substantially radial with
`respect to the mandrel 20 with the inner edges angled to
`correspond to the angled edges of the center member 60.
`Apair of opposing second members 56a—b are preferably
`positioned about the outer edges of the third members 58a—b
`as shown in FIGS. 5 through 7 of the drawings. The second
`members 56a—b each have a radial inner edge that corre
`sponds to the third members 58a—b and a substantially
`tapered outer edge as shown in FIGS. 5 through 7 of the
`drawings.
`A pair of ?rst members 54a—b are preferably positioned
`about the middle portion 26 of the mandrel 20 upon oppos
`ing sides of the second members 56a—b as shown in FIGS.
`1 through 7 of the drawings. The ?rst members 54a—b have
`an angled inner and outer edge as best shown in FIGS. 5
`through 7 of the drawings.
`As shown in FIGS. 1 through 7 of the drawings, a pair of
`gripping members 52a—b is positioned about the middle
`portion 26 of the mandrel 20 on opposing sides of the ?rst
`members 54a—b. The portion of the lower gripping member
`52b adjacent to the head member 30 is formed to correspond
`to the shape of the head member 30. The lower gripping
`member 52b has a tapered inner portion which forms a
`conical shape as best shown in FIGS. 5 through 7 of the
`drawings. The outer portion of the second gripping members
`52a—b preferably have a plurality of gripping ridges that
`preferably extend downwardly to engage the inner wall of
`the conduit 12. The gripping members 52a—b are preferably
`comprised of a metal that fractures along longitudinal chan
`nels when the gripping members 52a—b are forced upon the
`?rst members 54a—b. The gripping members 52a—b are
`preferably comprised of a material that is harder than the
`material utiliZed to construct the conduit 12.
`As shown in FIGS. 1 through 7, an upper main support 50
`surrounds the middle portion 26 of the mandrel 20 adjacent
`to the upper gripping member 52a. The lower edge of the
`upper main support 50 is formed to catchably engage the
`upper gripping member 52a. The upper inner portion of the
`upper main support 50 is preferably tapered outwardly in a
`conical shape for receiving the upper member 42. The upper
`member 42 is formed into a conical shape that surrounds the
`mandrel 20. The inner surface of the upper member 42 is
`preferably comprised of a gripping surface such as a plu
`rality of ridges or teeth for engaging the mandrel 20 during
`compression of the composite bridge plug system 10. An
`upper collar 40 is positioned about upper portion 24 of the
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`US 6,796,376 B2
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`5
`mandrel 20 adjacent to the upper member 42 and the upper
`main support 50 as shown in FIGS. 1 through 9 of the
`drawings.
`The upper collar 40, ?rst members 54a—b and the head
`member 30 are preferably comprised of a rigid and strong
`material such as but not limited to steel that is resistant to
`bending. The second members 56a—b, third members 58a—b
`and the center member 60 are preferably comprised of a
`malleable material Which are capable of forming a seal
`Within the conduit 12 When compressed and eXpanded such
`as but not limited to a polymeric material.
`In use, the user utiliZes the installation shaft 18 attached
`to the mandrel 20 via the coupler 16 to loWer the composite
`bridge plug system 10 to the location Within the conduit 12
`to be sealed. The user then slides an engaging tube 70 about
`the installation shaft 18 adjacent to the upper collar 40 as
`shoWn in FIG. 5 in a non-movable position. The user then
`pulls the mandrel 20 upWardly With the installation shaft 18
`While the engaging tube 70 remains stationary With respect
`to the conduit 12. As the mandrel 20 is draWn upWardly, the
`head member 30 is pulled upWardly thereby compressing the
`upper member 42, upper main support 50, gripping members
`52a—b, ?rst members 54a—b, second members 56a—b, third
`members 58a—b and center member 60 betWeen the head
`member 30 and the upper collar 40. The compression force
`?rst causes the center member 60, third members 58a—b and
`second members 56a—b to eXpand outWardly against the
`inner Wall of the conduit 12 Which is supported Within an
`outer Wall 14 as shoWn in FIG. 7 of the draWings. The
`compression force then causes the gripping members 52a—b
`to eXpand and break apart thereby penetrating the inner Wall
`of the conduit 12 to prevent movement of the composite
`bridge plug system 10 Within the conduit 12. The upper
`member 42 is compressed about the mandrel 20 thereby
`preventing the mandrel 20 from falling through into the
`conduit 12 after the coupler 16 is removed. After the
`composite bridge plug system 10 has been properly seated
`Within the conduit 12, the user then rotates the installation
`shaft 18 While pulling upWardly thereby breaking the shear
`portion 22. The upper portion 24 of the mandrel 20 is then
`removed from the conduit 12. When the user desires to drill
`out the composite bridge plug system 10 from the conduit
`12, the user drills into the mandrel 20 and the upper collar
`40 ?rst. The composite bridge plug system 10 may slide
`doWnWardly and rotate Within the conduit 12. As the com
`posite bridge plug system 10 slides doWnWardly, the head
`member 30 engages the engaging portion 21 of a loWer
`composite bridge plug system 10 Within the conduit 12
`Within the loWer slot 32 thereby preventing rotation of the
`composite bridge plug system 10. The composite bridge
`plug system 10 is then continued to be drilled or milled out
`as desired.
`Referring to FIG. 3, a slightly different embodiment of
`this invention is illustrated using identical reference char
`acters for identical elements and primed reference characters
`for the changed components. Instead of the third member
`58a having a ?at upper surface and the third member 58b
`having a ?at loWer surfaces as in FIGS. 6 and 7, the third
`members 58a‘ and 58b‘ have tapered upper and loWer
`surfaces. This requires the second elements 56a‘ and 56b‘ to
`have tapered mating surfaces but ?at opposing surfaces. This
`requires the ?rst members 54a‘ and 54b‘ to be modi?ed to
`provide complementary mating surfaces. Operation of the
`embodiment of FIG. 3 is essentially the same as the embodi
`ment of FIG. 6 and FIG. 7 because the gripping members
`52a—b and the malleable members are eXpanded in response
`to use of the coupler 16 and shaft 18.
`
`15
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`25
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`35
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`40
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`45
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`55
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`65
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`6
`As to a further discussion of the manner of usage and
`operation of the present invention, the same should be
`apparent from the above description. Accordingly, no further
`discussion relating to the manner of usage and operation Will
`be provided.
`With respect to the above description then, it is to be
`realiZed that the optimum dimensional relationships for the
`parts of the invention, to include variations in siZe, materials,
`shape, form, function and manner of operation, assembly
`and use, are deemed to be Within the expertise of those
`skilled in the art, and all equivalent structural variations and
`relationships to those illustrated in the draWings and
`described in the speci?cation are intended to be encom
`passed by the present invention.
`Therefore, the foregoing is considered as illustrative only
`of the principles of the invention. Further, since numerous
`modi?cations and changes Will readily occur to those skilled
`in the art, it is not desired to limit the invention to the eXact
`construction and operation shoWn and described, and
`accordingly, all suitable modi?cations and equivalents may
`be resorted to, falling Within the scope of the invention.
`I claim:
`1. A bridge plug comprising
`a mandrel having a longitudinal aXis, an upper portion, a
`middle portion and a loWer portion;
`a head member attached to the loWer portion of the
`mandrel;
`an upper collar positioned about the upper portion of the
`mandrel;
`an upper gripping member and a loWer gripping member
`positioned about the middle portion of the mandrel; and
`a mechanism for expanding the gripping members and for
`sealing the bridge plug against a surround tubular
`including
`a center member betWeen the gripping members having a
`tapered upWardly converging upper end and a tapered
`doWnWardly converging loWer end,
`a plurality of upper members betWeen the center member
`and the upper gripping member including a loWer
`element having a tapered upWardly converging loWer
`end in engagement With the center member and an
`upper element having a tapered upWardly converging
`upper end in engagement With the upper gripping
`member,
`a plurality of loWer members betWeen the center member
`and the loWer gripping member including an upper
`element having a tapered doWnWardly converging
`upper end in engagement With the center member and
`a loWer element having a tapered doWnWardly converg
`ing loWer end in engagement With the loWer gripping
`member,
`at least one of the center member, the upper members and
`the loWer members being malleable and capable of
`forming a seal When compressed.
`2. A bridge plug comprising
`a mandrel having a longitudinal aXis, an upper portion, a
`middle portion and a loWer portion;
`a head member attached to the loWer portion of the
`mandrel;
`an upper collar positioned about the upper portion of the
`mandrel;
`at least one gripping member positioned about the middle
`portion of the mandrel; and
`the at least one sealing member positioned about the
`middle portion of the mandrel and positioned betWeen
`the head member and the at least one gripping member;
`
`MEGCO Ex. 1005
`
`

`
`US 6,796,376 B2
`
`7
`the upper portion of the mandrel including a connecting
`portion for attachment to a setting tool and a shear
`portion betWeen the connecting portion and the middle
`portion of the mandrel so eXpanding the gripping
`member causes the upper portion of the mandrel to
`shear off at the shear portion Whereby the upper portion
`of the mandrel is removed from the bridge plug during
`setting of the bridge plug.
`the middle portion of the mandrel includes an upWardly
`facing engaging portion beloW the shear portion and the
`head member includes a slot for catchably retaining an
`engaging portion of a subjacent bridge plug having an
`identical engaging portion.
`3. The bridge plug of claim 2 Wherein the engaging
`portion is above the collar.
`4. A bridge plug comprising
`a mandrel having a longitudinal axis, an upper portion, a
`loWer portion, a middle portion and an upWardly facing
`
`10
`
`15
`
`8
`engaging portion in a set condition of the bridge plug
`for engaging a slot in a superposed bridge plug, the
`engaging portion comprising a torque transmitting con
`nection;
`a head member attached to the loWer portion of the
`mandrel having a slot for catchably retaining the engag
`ing portion of a superposed bridge plug;
`an upper collar positioned about the upper portion of the
`mandrel;
`at least one gripping member positioned about the middle
`portion of the mandrel;
`at least one sealing member positioned about the middle
`portion of the mandrel and positioned betWeen the head
`member and the at least one gripping member.
`
`*
`
`*
`
`*
`
`*
`
`*
`
`MEGCO Ex. 1005
`
`

`
`UNITED STATES PATENT AND TRADEMARK OFFICE
`CERTIFICATE OF CORRECTION
`
`: 6,796,376 B2
`PATENT NO.
`APPLICATION NO. : 10/189887
`DATED
`: September 28, 2004
`INVENTOR(S)
`: Warren L. Frazier
`
`Page 1 of 1
`
`It is certified that error appears in the above-identi?ed patent and that said Letters Patent is
`hereby corrected as shown below:
`
`Figure 3, “54b” should be --54b'--.
`
`Column 6, line 65: delete “the” from before “at least one sealing member”.
`
`Column 7, line 8: “the bridge plug.” should read --the bridge plug,--.
`
`Signed and Sealed this
`
`Twenty-second Day of December, 2009
`
`David J. Kappos
`Director ofthe United States Patent and Trademark O?ice
`
`MEGCO Ex. 1005
`
`

`
`UNITED STATES PATENT AND TRADEMARK OFFICE
`CERTIFICATE OF CORRECTION
`
`PATENT NO.
`APPLICATION NO.
`DATED
`INVENTOR(S)
`
`2 6,796,376 B2
`: 10/189887
`: September 28, 2004
`: Warren L. Frazier
`
`Page 1 Ofl
`
`It is certified that error appears in the above-identi?ed patent and that said Letters Patent is hereby corrected as shown below:
`
`Column 8, line 7: “superposed” should read --subjacent--.
`
`Signed and Sealed this
`
`David J. Kappos
`Director ofthe United States Patent and Trademark O?ice
`
`MEGCO Ex. 1005