U.S. patent number RE31,978 [Application Number 06/603,629] was granted by the patent office on 1985-09-03 for well tool having knitted wire mesh seal means and method of use thereof.
This patent grant is currently assigned to Baker Oil Tools, Inc.. Invention is credited to David M. McStravick.
United States Patent |
RE31,978 |
McStravick |
September 3, 1985 |
Well tool having knitted wire mesh seal means and method of use
thereof
Abstract
A well tool, such as a packer apparatus, is adaptable for
insertion on a conduit within a subterranean well having casing
therein. The well tool comprises a cylindrical mandrel which is
communicable to the conduit. Slip means are carried exteriorly
around the mandrel and are movable into expanded position for
anchoring the apparatus to the casing whereby subsequent
longitudinal movement of the apparatus in at least one direction is
prevented. Seal means are circumferentially extending exteriorly
around the mandrel and are urgable into sealing relation with the
casing to prevent fluid communication thereacross, the seal means
comprising at least one section of transversely compressible
seamless, knitted elements generally defined by a continuous series
of interlocking ductile metal-containing loop members.
Inventors: |
McStravick; David M. (Houston,
TX) |
Assignee: |
Baker Oil Tools, Inc. (Orange,
CA)
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Family
ID: |
26820303 |
Appl.
No.: |
06/603,629 |
Filed: |
April 25, 1984 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
Reissue of: |
122225 |
Feb 19, 1980 |
04326588 |
Apr 27, 1982 |
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Current U.S.
Class: |
166/387; 166/124;
166/134; 277/340 |
Current CPC
Class: |
E21B
33/1208 (20130101) |
Current International
Class: |
E21B
33/12 (20060101); E21B 033/128 (); E21B
033/129 () |
Field of
Search: |
;166/195,196,118,123,127,134,135,179,387,124 ;66/170,196
;277/117,118,121,122,125,188A,DIG.6 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Novosad; Stephen J.
Attorney, Agent or Firm: Norvell & Associates
Claims
What is claimed and desired to be secured by Letters Patent is:
1. A packer apparatus adaptable for insertion on a conduit within a
subterranean well having casing therein, said apparatus comprising:
a cylindrical mandrel communicable to said conduit; slip means
carried exteriorly around said mandrel and movable into expanded
position for anchoring said apparatus to said casing whereby
subsequent longitudinal movement of said apparatus in at least one
direction is prevented; and seal means circumferentially extending
exteriorly of said mandrel and urgeable into sealing relation with
said casing to prevent fluid transmission thereacross, said seal
means comprising at least one section of transversely compressible,
seamless, knitted elements generally defined by a continuous series
of interlocking ductile, metal-containing loop members, and further
comprising .[.an elastomeric.]. .Iadd.a sealing .Iaddend.material
introduced among said loop members.
2. The apparatus of claim 1 wherein said seal means further
comprises an asbestos-laden material interwoven among said loop
members.
3. The apparatus of claim 1 wherein said seal means further
comprises a bridging material introduced among said loop
members.
4. The apparatus of claim 1, 2 or 3 wherein said seal means further
comprises upper and lower sections of said seamless elements, and a
seal member comprising one of tetrafluoroethylene and flourinated
ethylene propylene spaced therebetween.
5. The apparatus of claim 4 further comprising at least one
circumferentially extending interiorly facing groove on said first
seal member to permit flexing of said first .[.seal.]. member
during setting of said apparatus.
6. The apparatus of claim 1, 2 or 3 wherein said seal means further
comprises upper and lower sections of said seamless elements, and a
seal member comprising one of tetrafluoroethylene and flourinated
ethylene propylene extending between first and second
circumferentially extending glass-filled seal members.
7. The apparatus of claim 1 or 2 wherein said seal means further
comprises a gapped secondary metal seal member, the gap on said
seal member radially increasing as said member is urged to sealing
position.
8. The apparatus of claim 7; and said second of seamless, knitted
elements extrude into said extended gap upon urging of said seal
means into sealed relation with said casing.
9. An apparatus adaptable for insertion on a first conduit within a
subterranean well having a second conduit extending therein, said
apparatus comprising: a cylindrical mandrel communicable to said
first conduit; slip means carried exteriorly around said mandrel
and movable into expanded position for anchoring said apparatus to
said second conduit whereby subsequent longitudinal movement of
said apparatus in at least one direction is prevented; and seal
means circumferentially extending exteriorly of said mandrel and
urgeable into sealing relation with said second conduit to prevent
fluid transmission thereacross, said seal means comprising at least
one section of transversely compressible seamless, knitted elements
generally defined by a continuous series of interlocking ductile,
metal-containing loop members, and further comprising .[.an
elastomeric.]. .Iadd.a sealing .Iaddend.material introduced among
said loop members.
10. The apparatus of claim 9 wherein said seal means further
comprises an asbestos-laden material interwoven among said loop
members.
11. The apparatus of claim 9 or 10 wherein said seal means further
comprises a gapped secondary metal seal member, the gap on said
seal member radially increasing as said member is urged to sealing
position.
12. The apparatus of claim 11; and said section of seamless,
knitted elements extrude into said extended gap upon urging of said
seal means into sealed relation with said casing.
13. The apparatus of claim 9 wherein said seal means further
comprises a bridging material introduced among said loop
members.
14. The apparatus of claim 9, 10 or 13 wherein said seal means
further comprises upper and lower sections of said seamless
elements, and a first seal member comprising one of
tetrafluoroethylene and flourinated ethylene propylene spaced
therebetween.
15. The apparatus of claim 14 further comprising at least one
circumferentially extending interiorly facing groove on said first
seal member to permit flexing of said first seal member during
setting of said apparatus.
16. The apparatus of claim 9, 10 or 13 wherein said seal means
further comprises upper and lower sections of said seamless
elements, and a first seal member comprising one of
tetrafluoroethylene and flourinated ethylene propylene extending
between first and second circumferentially extending glass-filled
seal members.
17. A packer apparatus adaptable for insertion on a conduit within
a subterranean well having casing therein, said apparatus
comprising: a cylindrical mandrel communicable to said conduit;
slip means carried exteriorly around said mandrel and movable into
expanded position for anchoring said apparatus to said casing
whereby subsequent longitudinal movement of said apparatus in at
least one direction is prevented; seal means circumferentially
extending exteriorly of said mandrel and urgeable into sealing
relation with said casing to prevent fluid transmission
thereacross, said seal means comprising at least one section of
transversely compressible, seamless, knitted elements generally
defined by a continuous series of interlocking ductile,
metal-containing loop members, and further comprising fibrous means
introduced among said metal-containing loop members for preventing
fluid transmission through said loop members.
18. The apparatus of claim 17 wherein said fibrous means comprises
an asbestos-laden material interwoven among said loop members.
19. The apparatus of claim 17 wherein said fibrous means comprises
.[.an elastomeric.]. .Iadd.a sealing .Iaddend.material introduced
among said loop members.
20. The apparatus of claim 17, 18 or 19 wherein said seal means
further comprises upper and lower sections of said seamless
elements, and a seal member comprising one of tetrafluoroethylene
and flourinated ethylene propylene extending between first and
second propylene spaced therebetween.
21. The apparatus of claim 17, 18 or 19 wherein said seal means
further comprises upper and lower sections of said seamless
elements, and a seal member comprising one of tetrafluoroethylene
and flourinated ethylene circumferentially extending glass-filled
seal members.
22. An apparatus adaptable for insertion on a first conduit within
a subterranean well having a second conduit extending therein, and
responsive to means for anchoring said apparatus at a predetermined
location in a subterranean well, said apparatus comprising seal
means for preventing fluid transmission thereacross, said seal
means comprising at least one section of transversely compressible,
seamless, knitted elements generally defined by a continuous series
of interlocking ductile metal-containing loop members and further
comprising fibrous means, introduced among said loop members, for
preventing fluid transmission through said knitted elements.
23. The apparatus of claim 22 wherein said interspersed fibrous
means further comprises .[.an elastomeric.]. .Iadd.a sealing
.Iaddend.material introduced among said loop members.
24. The apparatus of claim 22 wherein said interspersed fibrous
means comprises an asbestos-laden material interwoven among said
loop members.
25. An apparatus for insertion on a first conduit within a
subterranean well having a second conduit extending therein, said
apparatus comprising: a mandrel communicable to said first conduit;
slip means for anchoring said apparatus to said second conduit to
prevent longitudinal movement of said apparatus in at least one
direction; and seal means extending between said mandrel and said
second conduit to prevent fluid transmission thereacross, said seal
means comprising a first .Iadd.primary flexible .Iaddend.sealing
element and a second seal means adjacent thereto for preventing
extrusion of said primary flexible sealing element after initial
sealing relation is established, said second seal means comprising
a continuous series of interlocking ductile, metal-containing loop
members.
26. The apparatus of claim 25 wherein said second seal means
comprises transversely compressible, seamless, knitted elements
generally defined by a continuous series of interlocking ductile,
metal-containing loop members.
27. The apparatus of claim 25 or 26 wherein similar second seal
means are positioned on opposite sides of said first sealing
element and said .[.second.]. .Iadd.first .Iaddend.sealing element
comprises one of tetrafluoroethylene and flourinated ethylene
propylene.
28. An apparatus adaptable for insertion on a first conduit within
a subterranean well and responsive to means for positioning said
apparatus at a predetermined location in said subterranean well
against movement in at least one direction said apparatus
comprising seal means for preventing fluid transmission
thereacross, said seal means comprising a first sealing element and
a second sealing element adjacent thereto for preventing extrusion
of said first sealing element after initial sealing relation is
established, said second sealing element comprising a continuous
series of interlocking ductile, metal-containing loop members.
29. A method of establishing a seal in a subterranean well between
a first conduit and an inner wall of a second conduit in said well
to prevent fluid communication thereacross; comprising the steps of
positioning said second conduit with respect to said first conduit;
compressing a knitted wire mesh comprising seamless, knitted
elements generally defined by a continuous series of interlocking
ductile, metal-containing loop members with a fibrous material
introduced among said metal-containing loop members to urge said
knitted wire mesh into contact with both said first and second
conduits to form a seal therebetween.
30. A method of establishing a seal in a subterranean well between
a first conduit and an inner wall of a second conduit in said well
to prevent fluid communication thereacross; comprising the steps of
positioning and anchoring said second conduit with respect to said
first conduit: activating a main sealing component to urge said
main sealing component radially outward into sealing relationship
between said first and said second conduits; and comprising a
knitted wire mesh comprising seamless, knitted elements generally
defined by a continuous series of interlocking ductile,
metal-containing loop members to urge said knitted wire mesh
radially outward into contact with said first and second conduits,
urging said knitted wire mesh into contact with said main sealing
component immediately adjacent to said knitted wire mesh to fill
gaps through which said main sealing component would otherwise
extrude. .Iadd.
31. An apparatus adaptable for insertion on a first conduit within
a subterranean well having a second conduit extending therein, and
responsive to means for anchoring said apparatus at a predetermined
location in a subterranean well, said apparatus comprising seal
means for preventing fluid transmission thereacross, said seal
means comprising a first sealing element; extrusion preventing back
up means preventing extrusion of the first sealing element
therepast; and a resilient metallic element, transversely
compressible and conformable to the contour of the extrusion
preventing means, positioned between the extrusion preventing means
and the first sealing element. .Iaddend. .Iadd.
32. An apparatus adaptable for insertion on a first conduit within
a subterranean well having a second conduit extending therein, and
responsive to means for anchoring said apparatus at a predetermined
location in a subterranean well, said apparatus comprising seal
means for preventing fluid transmission thereacross, said seal
means comprising a first sealing element; extrusion preventing
means radially expandable into engagement with the second conduit
for preventing extrusion of the first sealing element therepast;
and a resilient metallic element, transversely compressible and
conformable to the contour of the extrusion preventing means,
positioned between the extrusion preventing means and the first
sealing element. .Iaddend. .Iadd.33. The apparatus of claim 32
wherein said resilient metallic element comprises a continuous
series of
interlocking metal-containing loop members. .Iaddend. .Iadd.34. The
apparatus of claim 33 wherein the extrusion preventing means
comprises a gapped secondary metal member, the gap thereon radially
increasing as said member is urged into engagement with the second
conduit. .Iaddend.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a tool insertable within a subterranean
well comprising a seal means defined by a continuous series of
transversely compressible interlocking ductile metal-containing
loop members.
2. Description of the Prior Art
During certain operations in a subterranean oil or gas well, such
as during a completion or workover procedure, it is common practice
to utilize a packer assembly, bridge plug or other isolation tool
to separate one section or zone of a well from another section or
zone. Such apparatuses typically employ elastomeric sealing
members, utilized alone or in combination with other sealing
elements, such as virgin tetrafluoroethylene and/or glass-filled
tetrafluoroethylene components (sometimes referred to under the
tradename "Teflon"), as the primary means for isolating the section
or zone, the seal means, upon manipulation of the tool, sealing
against the internal wall of the casing. In extremely hostile well
environments, such as those wherein the bottom hole temperature is
in excess of about 350.degree. F. and/or exposed to considerably
high concentrations of H.sub.2 S and or CO.sub.2, an
acrylonitrile-type elastomeric substance has been utilized in the
seal means of the tool, to provide somewhat effective working life
for the tool. The use of such acrylonitrile-type elastomers is not
entirely satisfactory because this material can, with time,
chemically degrade to the extent that its elastomeric properties
are lost in the hostile environment, described above, Other
materials, such as tetrafluoroethylene have the desired chemical
inertness, but tend to extrude under high temperature and pressure.
Additionally, when metallic back-up rings are utilized in such seal
systems, wherein a gap is defined in the metallic ring upon
expansion thereof into engagement with the casing, "gaps" or
"voids" will be necessarily defined at one or more points thereon
which require sealing with respect to the casing in order to insure
the integrity of the entire seal system.
The present invention is directed to a seal means for use in a well
tool, such as a well packer, which prevents extrusion of such inert
sealing elements, described above, and which will fill "gaps" and
"voids" within metallic back-up rings within the seal system.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a longitudinally extending sectional view, the left hand
side showing the exterior, and the right hand side being a cut-away
view showing the interior, of a well packer apparatus employing the
present invention, prior to setting in a well having casing
therein.
FIG. 2 is a view similar to that illustrated in FIG. 1 showing the
component parts of the apparatus subsequent to setting of the
apparatus, the seal means being illustrated in sealing relation to
the casing, the slips being in anchored position.
FIG. 3 is an enlarged perspective view of the seal assembly
illustrated in FIGS. 1 and 2.
FIG. 3A is a cross-sectional view taken along line 3A--3A of FIG. 3
illustrating, in pre-crushed state the continuous series of
interlocking ductile metal-containing loop members utilized in the
seal means of the present invention.
FIG. 4 is a perspective view of the seal means subsequent to the
setting of the apparatus in the well.
SUMMARY OF THE INVENTION
The present invention is directed to a well tool, such as a well
packer, bridge plug, or other sealing means which is adaptable for
insertion in a conduit within a subterranean well and for selective
sealing engagement with a second conduit, such as a casing. The
well tool comprises a cylindrical mandrel communicable to the first
conduit, such as the tubular work or production string. Slip means
are carried exteriorly around the mandrel and are moveable into
expanded position for anchoring the apparatus to the second
conduit, or casing, whereby subsequent longitudinal movement of the
apparatus in at least one direction is prevented. Seal means
circumferentially extend exteriorly of the mandrel and are urged
into sealing relation with the second conduit to prevent fluid
transmission thereacross, the seal means comprising at least one
section of transversely compressible seamless, knitted elements
generally defined by a continuous series of interlocking ductile
metal-containing loop members. In a preferred form, the seal means
may further comprise as asbestos-laden material innerwoven among
the loop members. In still another preferred form, the seal means
may additionally comprise upper and lower sections of the seamless
elements, together with a seal member comprising one of
tetrafluoroethylene and flourinated ethylene propylene. Metal
extrusion barriers or secondary supports, together with
glass-filled seal members, also may be incorporated within the seal
means.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Now referring to FIG. 1, the apparatus A which is illustrated as a
well packer, is carried on a tubular conduit TC and is inserted
within a well W extending to a production zone Z, the well W having
a string of casing C extending from the zone Z to the top of the
well, the casing C having perforations P therethrough communicating
from the zone Z to within the annulus AL.
The apparatus A is run on the tubular conduit TC within the well W
below and in operational communication with a setting tool ST
having an internal setting tool activator STA affixed by threads
10A to a longitudinally extending cylindrical mandrel in the
apparatus A, the setting tool ST also having a setting tool sleeve
STS formed on the exterior of the setting tool ST. Together, the
setting tool sleeve STS and the setting tool activator STA provide
a "push-pull" action upon the apparatus A during the setting
thereof.
The setting tool may be one of a number of conventionally and
commercially known setting tools, and the particular setting tool
or mechanism utilized does not form a part of the present
invention. Typical of such setting tools is that as shown in the
Technical Data Manual Unit No. 2717 of the Baker Packers Division,
Baker International Corporation and the Baker Packers Model "J"
Hydraulic Setting Assembly, Product No. 413-71. However, any
setting tool which is adaptable to provide a "push-pull" action, as
described above, may be used in conjunction with the apparatus A
for the setting thereof.
The mandrel 10 has defined thereon a series of exteriorly defined
circumferentially extending wicker elements 11 which, together with
engageable wickers 18 on a body lock ring 17 carried exteriorly
around the mandrel 10 are utilized in the setting of the apparatus
A. A hole 12 is defined in the mandrel 10 for receipt of one end of
a shear screw 24 protruding therein and out of an upper cone
element 23 for initial securement of the upper cone element 23
around the mandrel 10. A similar hole 13 holds the exterior
inwardly protruding end of a lower shear screw 40 insertable
therein and extending interiorly from a lower cone element 39. The
mandrel 10 is terminated at its lower end by a series of threads 14
for affixation of a ported bottom sub element 43.
The wickered lock ring 17 is secured at threads 16 to a lock ring
protector 15 having an upper end 15A receiving the lower end of the
setting tool sleeve STS, prior to the setting of the apparatus A.
The lower end 19 of the lock ring protector abuts upon the upper
face of a circumferentially extending series of slotted upper slips
20 having exteriorly protruding teeth 21 thereon which, upon
setting of the apparatus A, will break up along longitudinal
grooves and then contact and grasp the inner wall of the casing C
for anchoring of the apparatus A relative to the casing C. An upper
cone element 23 is carried below the upper slips 20 and
circumferentially around the exterior of the mandrel 10, the upper
cone 23 having a slanted guide surface 22 for guiding and urging
the upper slips 20 outwardly into anchored position. The upper
shear screws 24 is carried within a bore of the upper cone 23 and
has its innermost end protruding outwardly of the cone 23 and into
the hole 12 fo initial securement of the upper cone 23 to the
mandrel 10.
An upper triangularly shaped cone ring element 25 is carried
circumferentially around the mandrel 10 and below the upper cone 23
and is initially shouldered against said upper cone 23. This upper
cone ring 25 typically is of a metallic substance and, when urged
outwardly into engagement with the casing C, provides a metal
back-up bridging means to prevent extrusion of other components of
the seal means and further provide support to the sealing means.
The cone ring 25 contains a groove 27 profiled on its lower face
for receipt of a companion tongue 28 of a similarly constructed
element ring 26, of triangular configuration. It should be noted
that each of the rings 25 and 26 contain a gap, such as 29 shown in
FIG. 3 which is enlarged (as shown in FIG. 4) upon activation of
the apparatus A into sealing engagement with the casing C, the
"gap" in the cone ring 25 being spaced 180.degree. from the "gap"
in the element ring 26. Such a gap is a construction detail of the
rings 25-26 enabling each of the said rings to radially expand into
engagement with the internal wall of the casing C.
Below the element ring 26 and extending circumferentially around
the mandrel 10 is a section of transversely compressible seamless,
knitted elements generally defined by a continuous series of
interlocking ductile, metal-containing loop members. Such an
element is described in U.S. Pat. No. 2,761,203, entitled
"Resilient Gasket Forming Material And Method Of Reducing Same",
and No. 3,033,722, entitled "Compressible Metal Gasket And Method
Of Making Same", each being assigned to Metex Corporation of
Edison, N.J., from which such a product can be readily
obtained.
Now referring specifically to FIG. 3A, this element consists of
continuous series 30A, 30B, 30C, etc., of interlocking loops
knitted in a tubular form, allowing two-way movement in the wire
plane, affording unusual flexibility and resiliency, even under
heavy compression loads and exposure to extreme temperatures. It
has been found that knitted wire yields to applied force, yet
maintains its compressive stress. Since there are no ribs, seams or
other weak areas in this construction, the seal has a uniform
strength over its entire area. When used in combination with other
basic sealing material, such as asbestos-laden cords 30D, 30E, 30F,
etc., interwoven between one or more of the loops 30A, 30B, 30C,
etc., the knitted wire serves as a "backbone" sleeve or expander,
imparting its resiliency to the combined element. This seamless,
knitted element is compressed to contour to the general
requirements of contour of the apparatus and may be fabricated from
almost any material or combination of materials that may be drawn
or filament form, such as stainless steel wire, or other ductile
metals, such as aluminum, copper and special alloys, in combination
wth the asbestos-laden material, other synthetic fibers, polymers
and yarns. Such a knitted element is further disclosed in Bulletin
No. M1-50 of the Metex Thermal-Mechanical Group, Metex
Corporation.
Referring to FIG. 3, below the upper knitted wire mesh element 30
and communicating therewith is a secondary seal element 31, which
may be typically a teflon or glass-filled teflon ring element. The
main sealing component of the seal means in the apparatus A is
defined as a virgin teflon ring element 32, preferably having
grooved internally spaced circumferentially extending rib elements
32A thereon to permit flexing of the seal 32 during setting.
Below the main seal element 32 is provided a lower, preferably
glass-filled teflon secondary seal element 33 which, in turn,
contacts a second or lower knitted wire mesh element 34 of the same
or similar construction as the upper knitted wire mesh element 30.
Similarly, the seal means is terminated at its lowermost end by the
companion lower cone 39 and lower element rings 35 and 38,
respectively, of similar construction and design as the rings 25
and 26. A groove and tongue configuration 36 and 37, respectively,
is defined between the rings 38 and 35 for interengagement
thereof.
Carried circumferentially around the exterior of the mandrel 10 and
below the lower element ring 38 is a lower cone element 39
receiving a lower shear screw element 40 therethrough having its
innermost interior end received within the hole 13 in the mandrel
10 for securing the lower cone 39 to the mandrel 10 prior to the
setting of the apparatus A. The lower cone 39 has a guide 39A for
directing a series of slotted lower slip elements 41 having teeth
42 into radially extended positioning for securing the teeth 42
into the inner wall of the casing C to assist in anchoring the
apparatus A unto the inner wall of the casing C.
OPERATION
The apparatus A is run into the well on a tubular conduit TC, such
as the tubing string or the like, and is located above perforations
P within the zone Z. The setting tool ST typically will be
activated by pumping or gravitating a ball element through the
tubular conduit TC until it lands upon a seat (not shown) in the
setting tool ST. Thereafter, pressure is applied within the tubular
conduit TC and against the ball and seat for transmission of
hydraulic force through setting tool ST. The setting tool sleeve
STS typically will be urged downwardly while the setting tool
activator STA is stabilized or urged upwardly. This "push-pull"
force is transmitted between the mandrel 10 and the components of
the apparatus A extending therearound, and, because of the
innerengagement of the bottom sub 43 to the mandrel 10 at threads
14, such action will cause the lock ring 17 to shift relative to
the mandrel 10 upon innerengagement of the wickers 11-18, thereby
urging the lock ring protector 15 against the upper slips 20 which
are moved along the guide 22 of the upper cone 23 until the teeth
21 contact and engage the inner wall of the casing C. Concurrently,
the force is transmitted from the upper slips 20 through the cone
23 and, subsequent to shearing of the shear screw 24, through the
upper cone ring 25 and element ring 26, whereby the rings 25-26
expand radially outwardly, extending the length of the gap 29,
until the rings 25 and 26 contact the inner wall of the casing C.
The setting force continues to be transmitted to the upper knitted
wire mesh element 30 which is urged outwardly into contact with the
casing C to prevent extrusion of the ring 31 therebelow and to fill
the gap defined in the element ring 26. The setting force continues
to be transmitted through the apparatus A for outward urging of the
virgin teflon ring 32, the lower glass-filled ring 33, the lower
knitted wire mesh element 34, the lower cone ring 35 and the lower
element ring 38.
It should be noted that as the lower knitted wire mesh element 34
extends outwardly, it will fill the extended "gap" or "void" in the
lower cone ring 35 as it extends radially outwardly into sealing
engagement with the casing C. The force continues to be transmitted
to the lower cone members 39 which, by means of the guide 39A, urge
the lower slip members 41 outwardly away from the apparatus A, such
that the teeth 42 grasp the casing C, subsequent to shearing of the
lower shear screw 40 from position on the mandrel 10.
The complete setting position of the apparatus A is shown in FIG. 2
with the upper and lower slip elements 20 and 41 respectively
engaging in the wall of the casing C and the seal means being in
sealed relationship with the casing C. The relative position of the
components of the seal means in their expanded mode are as shown in
FIG. 4.
Although the invention has been described in terms of specified
embodiments which has been set forth in detail, it should be
understood that this is by illustration only and that the invention
is not necessarily limited thereto, since alternative embodiments
and operating techniques will become apparent to those skilled in
the art in view of the disclosure. Accordingly, modifications are
contemplated which can be made without departing from the spirit of
the described invention.
* * * * *