U.S. patent application number 12/888809 was filed with the patent office on 2011-02-03 for gasket and mandrel assembly for pipe joints.
This patent application is currently assigned to PRESS-SEAL GASKET CORPORATION. Invention is credited to Timothy A. Andrews, Andrew J. Happel, Michael R. Miller, James W. Skinner.
Application Number | 20110024993 12/888809 |
Document ID | / |
Family ID | 46205863 |
Filed Date | 2011-02-03 |
United States Patent
Application |
20110024993 |
Kind Code |
A1 |
Happel; Andrew J. ; et
al. |
February 3, 2011 |
GASKET AND MANDREL ASSEMBLY FOR PIPE JOINTS
Abstract
A gasket and mandrel assembly, including a gasket having an
annular main body portion with an anchor flange and a pipe sealing
portion. The gasket is foldable between a folded position in which
the pipe sealing portion is disposed substantially within the main
body portion and an unfolded position in which the pipe sealing
portion extends outwardly of the main body portion along its
longitudinal axis. A pair of mandrels are respectively fitted on
opposite sides of the folded gasket to enclose most of the gasket
for casting the gasket within a wall in a concrete structure. At
least one of the mandrels includes an annular outer surface aligned
parallel or substantially parallel with the longitudinal axis of
the gasket. Removal of the mandrels results in the cast opening in
the concrete structure having a circular inner surface which is
disposed parallel or substantially parallel to the longitudinal
axis of the gasket and the resulting opening such that, if the
gasket should fail, the gasket may be removed from the opening and
an expansion-type gasket may be sealingly compressed against the
opening surface with an expansion band assembly.
Inventors: |
Happel; Andrew J.; (Fort
Wayne, IN) ; Andrews; Timothy A.; (Marion, IN)
; Miller; Michael R.; (Churubusco, IN) ; Skinner;
James W.; (Fort Wayne, IN) |
Correspondence
Address: |
BAKER & DANIELS LLP;111 E. WAYNE STREET
SUITE 800
FORT WAYNE
IN
46802
US
|
Assignee: |
PRESS-SEAL GASKET
CORPORATION
Fort Wayne
IN
|
Family ID: |
46205863 |
Appl. No.: |
12/888809 |
Filed: |
September 23, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
11352498 |
Feb 10, 2006 |
7827665 |
|
|
12888809 |
|
|
|
|
10887427 |
Jul 8, 2004 |
7028972 |
|
|
11352498 |
|
|
|
|
Current U.S.
Class: |
277/606 ;
249/57 |
Current CPC
Class: |
Y10T 29/49719 20150115;
B28B 23/0043 20130101; F16L 5/10 20130101; E04G 15/063 20130101;
Y10T 29/4973 20150115 |
Class at
Publication: |
277/606 ;
249/57 |
International
Class: |
F16L 5/02 20060101
F16L005/02; B22C 9/24 20060101 B22C009/24 |
Claims
1. A gasket and mandrel assembly, comprising: a gasket, comprising:
an annular main body portion; an anchor flange extending radially
outwardly from said main body portion; a pipe sealing portion
extending from said main body portion, said pipe sealing portion
positionable in a folded condition in which said pipe sealing
portion is disposed at least partially within said main body
portion; and a mandrel assembly having a longitudinal axis,
comprising: a first mandrel including at least one annular outer
surface disposed at an angle of between 0.5.degree. and 7.degree.
with respect to said longitudinal axis; and a second mandrel made
at least in part of a resilient material, said first and second
mandrels cooperable with one another to substantially enclose at
least a portion of said gasket with said anchor flange of said
gasket exposed externally of said mandrels.
2. The gasket and mandrel assembly of claim 1, wherein said at
least one annular outer surface of said first mandrel is disposed
at an angle of between 0.5.degree. and 4.degree. with respect to
said longitudinal axis.
3. The gasket and mandrel assembly of claim 1, wherein said at
least one annular outer surface of said first mandrel is disposed
at an angle of between 1.5.degree. and 2.5.degree. with respect to
said longitudinal axis.
4. The gasket and mandrel assembly of claim 1, wherein said first
mandrel is formed at least in part of a rigid material and includes
an annular cavity within which at least a portion of said gasket is
receivable.
5. The gasket and mandrel assembly of claim 1, wherein said first
and second mandrels include cooperating engagement structures.
6. The gasket and mandrel assembly of claim 1, wherein said pipe
sealing portion of said gasket is foldable between a first position
in which said pipe sealing portion is disposed substantially within
said main body portion of said gasket and a second position in
which said pipe sealing portion extends away from said main body
portion along said longitudinal axis.
7. The gasket and mandrel assembly of claim 1, wherein said anchor
flange comprises at least one undercut, at least a portion of one
of said first and second mandrels received within said
undercut.
8. The gasket and mandrel assembly of claim 1, wherein one of said
first and second mandrels includes an annular front face disposed
generally transverse to said longitudinal axis, said front face
having a convex profile, and the other of said first and second
mandrels includes an annular rear face disposed generally
transverse to said longitudinal axis, said rear face having a
concave profile.
9. The gasket and mandrel assembly of claim 1, wherein said outer
annular surface is formed as a portion of a separate component
attached to said first mandrel.
10. A mandrel assembly for use in casting a gasket within a wall of
a structure, comprising: a first mandrel having a longitudinal
axis, a first face disposed substantially transverse to said
longitudinal axis, and at least one annular outer surface disposed
at an angle of between 0.5.degree. and 7.degree. with respect to
said longitudinal axis; and a second mandrel formed at least in
part of a resilient material and having a second face disposed
substantially transverse to said longitudinal axis.
11. The mandrel assembly of claim 10, wherein said at least one
annular outer surface of said first mandrel is disposed at an angle
of between 0.5.degree. and 4.degree. with respect to said
longitudinal axis.
12. The mandrel assembly of claim 10, wherein said at least one
annular outer surface of said second mandrel is disposed at an
angle of between 1.5.degree. and 2.5.degree. with respect to said
longitudinal axis.
13. The mandrel assembly of claim 10, wherein said first mandrel is
formed at least in part of a rigid material and includes an annular
cavity.
14. The mandrel assembly of claim 10, wherein said first face of
said first mandrel has a convex profile, and said second face of
said second mandrel has a concave profile.
15. The mandrel assembly of claim 10, wherein said first and second
mandrels include cooperating engagement structures.
16. The mandrel assembly of claim 10, wherein said outer annular
surface is formed as a portion of a separate component attached to
said first mandrel.
17-23. (canceled)
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The present application is a continuation-in-part of U.S.
patent application Ser. No. 10/887,427, entitled GASKET AND MANDREL
ASSEMBLY FOR PIPE JOINTS, filed on Jul. 8, 2004.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a gasket and mandrel
assembly, including a flexible gasket and a pair of mandrels, for
use in casting the gasket in place within the wall of a concrete
structure, wherein the gasket provides a sealed joint between the
concrete structure and a pipe.
[0004] 2. Description of the Related Art
[0005] In general, pipe joint gaskets or seals are well known in
the art for sealing a pipe joint connection between a pipe and a
structure to which the pipe is connected. In one particular
application, for example, a pipe joint is formed between a sewer
pipe and a concrete manhole riser, in which a sewer pipe is
inserted through a gasket which is embedded within the concrete
wall of the manhole riser. In other applications, pipe joints may
be provided to connect pipes to septic tanks, for example, or may
be provided in any other structures to which pipes are
connected.
[0006] One known type of pipe joint connection between a concrete
structure and a pipe is shown in FIGS. 1 and 2. Referring to FIG.
1, an annular cast-in gasket 10 is shown, which is cast within the
wall of a concrete structure 12. Concrete structure 12 typically
includes a curved wall 14 having an opening 16 which is formed
within wall 14 when gasket 10 is cast in place within wall 14.
Gasket 10 generally includes an anchoring portion 18 extending
radially outwardly thereof for embedment within the concrete of
structure 12, and a compressible sealing portion 20 extending
radially inwardly thereof to sealingly engage the outer surface of
a pipe 22 inserted through gasket 10, as shown in FIG. 2, to
provide a fluid tight seal between pipe 22 and wall 14 of concrete
structure 12.
[0007] Gasket 10 is cast within concrete structure 12 using a pair
of mandrels, including conically-shaped front and rear mandrels 24
and 26, respectively. Front and rear mandrels 24 and 26 are each
generally annular in shape, and include outer walls 28 and 30,
respectively, which are disposed at an angle which is inclined at
least 10.degree. with respect to the common longitudinal axis
L.sub.1-L.sub.1 of gasket 10 and the resulting opening 16 which is
formed in concrete structure 12. In particular, it is desirable
that outer walls 28 and 30 of mandrels 24 and 26 are inclined at an
angle of at least 10.degree. with respect to the longitudinal axis
L.sub.1-L.sub.1 in order to facilitate the easy removal of mandrels
24 and 26 in opposite directions along longitudinal axis
L.sub.1-L.sub.1 from opening 16 in the concrete structure 12 after
the cast concrete has cured.
[0008] After mandrels 24 and 26 are removed, gasket 10 is anchored
in place by the embedment of anchor portion 18 of gasket 10 within
the cured concrete of structure 12. It is also desirable for the
inner surfaces of opening 16, which are formed by outer walls 28
and 30 of mandrels 24 and 26, to be angled at least 10.degree. with
respect to the longitudinal axis L.sub.1-L.sub.1 in order to
accommodate tilting movement of pipe 22 in which pipe 22 becomes
misaligned with longitudinal axis L.sub.1-L.sub.1. Other similar
gaskets which are cast in place in a similar manner to the
foregoing gasket 10, using similar mandrels, may include a pipe
sealing portion which extends along the longitudinal axis
L.sub.1-L.sub.1 of the gasket, with the pipe sealing portion
externally clamped to the outer surface of a pipe using a clamping
band to provide a fluid tight seal between the gasket and the
pipe.
[0009] Although the foregoing types of gaskets and mandrels have
been effective for forming concrete structures with cast-in gaskets
for providing sealed joints between the concrete structures and
pipes, a problem with the gaskets and mandrels is that it is
possible to cast the gaskets incorrectly within the concrete
structures when the structures are initially formed, such as, for
example, positioning the gasket incorrectly during casting of the
structure. Failure of the gasket in the field after a pipe is
connected to the gasket is also possible. In each of these
circumstances, repairing or replacing the gasket is often
difficult, if not impossible, without re-casting a portion of the
concrete structure or replacing the entire concrete structure.
[0010] What is needed is a gasket and mandrel assembly for pipe
joints which is an improvement over the foregoing.
SUMMARY OF THE INVENTION
[0011] The present invention provides a gasket and mandrel
assembly, including a gasket having an annular main body portion
with an anchor flange and a pipe sealing portion. The gasket is
foldable between a folded position in which the pipe sealing
portion is disposed substantially within the main body portion and
an unfolded position in which the pipe sealing portion extends
outwardly of the main body portion along its longitudinal axis. A
pair of mandrels are respectively fitted on opposite sides of the
folded gasket to enclose most of the gasket for casting the gasket
within a wall in a concrete structure. At least one of the mandrels
includes an annular outer surface aligned parallel or substantially
parallel with the longitudinal axis of the gasket. Removal of the
mandrels results in the cast opening in the concrete structure
having a circular inner surface which is disposed parallel or
substantially parallel to the longitudinal axis of the gasket and
the resulting opening such that, if the gasket should fail, the
gasket may be removed from the opening and an expansion-type gasket
may be sealingly compressed against the opening surface with an
expansion band assembly.
[0012] In one embodiment, the first mandrel defines a longitudinal
axis and is made of a relatively rigid material, and includes a
first face disposed substantially transverse to the longitudinal
axis and having a convex profile, a cavity, and at least one
annular outer surface disposed at an angle between 0.5.degree. and
7.degree. with respect to longitudinal axis. A second mandrel is
made of a relatively resilient material, and includes a second face
disposed transverse to the longitudinal axis and having a concave
profile. In use, the first and second mandrels are cooperable with
one another to substantially enclose a folded gasket therebetween,
with the anchoring flange of the gasket remaining external of the
mandrels for embedment within a cast, curved wall. The relatively
resilient material of the second mandrel allows the second mandrel
to be easily pulled away or separated from the first mandrel and
the surrounding concrete after the wall is cast, and the annular
outer wall of the first mandrel provides an inner annular wall
within the resulting opening in the concrete structure to which an
expansion-type gasket may be installed should the original, cast-in
gasket fail.
[0013] Advantageously, should the first cast-in gasket fail, the
gasket may be removed and a second, expansion-type gasket may be
installed within the opening of the concrete structure without
requiring repair or replacement of the concrete structure
itself.
[0014] In one form thereof, the present invention provides a gasket
and mandrel assembly, including a gasket, including an annular main
body portion; an anchor flange extending radially outwardly from
the main body portion; a pipe sealing portion extending from the
main body portion, the pipe sealing portion positionable in a
folded condition in which the pipe sealing portion is disposed at
least partially within the main body portion; and a mandrel
assembly having a longitudinal axis, including a first mandrel
including at least one annular outer surface disposed at an angle
of between 0.5.degree. and 7.degree. with respect to the
longitudinal axis; and a second mandrel made at least in part of a
resilient material, the first and second mandrels cooperable with
one another to substantially enclose at least a portion of the
gasket with the anchor flange of the gasket exposed externally of
the mandrels.
[0015] In another form thereof, the present invention provides a
mandrel assembly for use in casting a gasket within a wall of a
structure, including a first mandrel having a longitudinal axis, a
first face disposed substantially transverse to the longitudinal
axis, and at least one annular outer surface disposed at an angle
of between 0.5.degree. and 7.degree. with respect to the
longitudinal axis; and a second mandrel formed at least in part of
a resilient material and having a second face disposed
substantially transverse to the longitudinal axis.
[0016] In a further form thereof, the present invention provides a
method of forming and maintaining a concrete structure, including
the steps of casting a first annular gasket within a wall of the
structure using at least one mandrel, the gasket including an
anchor flange embedded within the wall, the mandrel having at least
one annular outer surface disposed at an angle of between
0.5.degree. and 7.degree. with respect to a longitudinal axis of
the mandrel, whereby the mandrel forms an annular opening within
the wall having at least one annular inner surface disposed at an
angle of between 0.5.degree. and 7.degree. with respect to the
longitudinal axis; removing at least a portion of the first gasket
from the wall; and installing a second gasket within the opening in
the wall using an expansion band to sealingly compress at least a
portion of the second gasket to the annular inner surface of the
opening.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] The above-mentioned and other features and advantages of
this invention, and the manner of attaining them, will become more
apparent and the invention itself will be better understood by
reference to the following description of an embodiment of the
invention taken in conjunction with the accompanying drawings,
wherein:
[0018] FIG. 1 is a vertical sectional view of a known gasket and
mandrel assembly, showing the use of a pair of mandrels to cast the
gasket within a wall of a concrete structure;
[0019] FIG. 2 is a vertical sectional view of the gasket of FIG. 1
cast within the concrete structure, with the mandrels removed and a
pipe installed through the gasket;
[0020] FIG. 3 is a sectional view of a gasket according to the
present invention, the gasket shown in an unfolded position;
[0021] FIG. 4 is an exploded, horizontal sectional view showing the
gasket of FIG. 3 in a folded position, together with a pair of
mandrels for use in casting the gasket within a wall of a concrete
structure in accordance with the present invention;
[0022] FIG. 5 is a horizontal sectional view through a concrete
structure, showing the gasket and mandrels of FIG. 4;
[0023] FIG. 6 is a horizontal sectional view through the concrete
structure of FIG. 5, illustrating the removal of the mandrels after
curing of the concrete;
[0024] FIG. 7 is a horizontal sectional view through the concrete
structure of FIG. 6, showing the gasket disposed in an unfolded
position with the pipe sealing portion of the gasket sealingly
connected to a pipe with a clamping band;
[0025] FIG. 8 is a horizontal sectional view of the gasket and the
concrete structure of FIGS. 6 and 7, showing the removal of the
gasket from the opening in the concrete structure by cutting the
gasket in the upper portion of FIG. 8, or alternatively, by pulling
the anchor flange of the gasket outwardly of the concrete
structure, as shown in the lower portion of FIG. 8;
[0026] FIG. 9 is a horizontal sectional view through the concrete
structure of FIG. 8 with the first gasket of FIGS. 3-8 removed
therefrom, and showing a second, expansion-type gasket installed
within the opening of the structure with an expansion band, the
gasket sealingly connected to a pipe with a clamping band; and
[0027] FIG. 10 is a first perspective exploded view of first and
second mandrels of a mandrel assembly in accordance with another
embodiment of the present invention;
[0028] FIG. 11 is a second perspective exploded view of the first
and second mandrels of FIG. 10;
[0029] FIG. 12 is a sectional view through a cast wall of a
concrete structure, showing the first and second mandrels
cooperating with one another to substantially enclose a folded
gasket therebetween;
[0030] FIG. 13 is a fragmentary view of a portion of the first and
second mandrels, showing an annular lip of the first mandrel
cooperating with an annular recess in the second mandrel;
[0031] FIG. 14 is a partially sectioned view of the wall of FIG.
12, illustrating the removal of the first and second mandrels after
the wall has been cast;
[0032] FIG. 15 is a sectional view of a mandrel assembly according
to a further embodiment; and
[0033] FIG. 16 is a sectional view of a mandrel assembly according
to a still further embodiment.
[0034] Corresponding reference characters indicate corresponding
parts throughout the several views. The exemplification set out
herein illustrates one preferred embodiment of the invention, in
one form, and such exemplification is not to be construed as
limiting the scope of the invention any manner
DETAILED DESCRIPTION
[0035] Referring to FIGS. 3 and 4, a gasket and mandrel assembly 32
in accordance with the present invention is shown, including a
cast-in type gasket 34, shown in FIG. 3, which may be cast in place
within the wall of a concrete structure using mandrels 36 and 38,
shown in FIG. 4. Gasket 34 may be made from a suitable flexible
elastomeric material, such as rubber or neoprene, for example, and
generally includes an annular main body portion 40, an annular
intermediate portion 42, and an annular pipe sealing portion
44.
[0036] Main body portion 40 of gasket 34 includes anchor flange 46
extending radially outwardly therefrom, with anchor flange 46
including an enlarged anchoring end 48 and a pair of undercuts 50
disposed on opposite sides of anchor flange 46 proximate main body
portion 40 for the purpose described below. Intermediate portion 42
is connected to main body portion 40 by a first annular hinge
section 52, which may be formed as a groove or weakening in gasket
34, and intermediate portion 42 is connected to pipe sealing
portion 44 by a second annular hinge section 54, which also may be
formed as a groove or weakening in gasket 34. Pipe sealing portion
44 includes at least one clamping band seat 56 for receipt of a
clamping band as described below to sealingly connect pipe sealing
portion 44 of gasket 34 to the outer surface of a pipe, and the
inner surface of pipe sealing portion 44 includes a plurality of
compressible sealing ridges 58 which are compressible against the
outer surface of a pipe.
[0037] In FIG. 3, gasket 34 is shown in an unfolded or extended
position in which intermediate portion 42 and pipe sealing portion
44 are extended outwardly of main body portion 40 along
longitudinal axis L.sub.1-L.sub.1 of gasket 34, with intermediate
portion 42 disposed at a sloped angle with respect to longitudinal
axis L.sub.1-L.sub.1 of gasket 34 and pipe sealing portion 44
disposed generally radially inwardly of main body portion 40. In
FIG. 4, gasket 34 is shown in a folded position in which
intermediate portion 42 is folded about hinge section 52 radially
inwardly of main body portion 40, and pipe sealing portion 44 is
folded about second hinge section 54 radially inwardly of
intermediate portion 42.
[0038] A pair of annular mandrels 36 and 38, including first or
outer mandrel 36 and second or inner mandrel 38, are used to cast
gasket 34 within the wall of a concrete structure in the manner
described below. Mandrels 36 and 38 may be formed of metal or of a
rigid plastic material, for example. Outer mandrel 36 generally
includes a body including annular outer wall 60 with outer surface
62, and annular inner wall 64 disposed radially inwardly of outer
wall 60 and including an inner surface 66 defining a central
opening through mandrel 36. Front wall 68 connects outer wall 60
and inner wall 64, is annular in shape, and has a convex profile,
as shown in FIG. 4. Outer mandrel 36 additionally includes an
annular cavity 70 defined between outer wall 60, inner wall 64, and
front wall 68 which opens toward the rear side of mandrel 36
opposite front wall 60.
[0039] Inner mandrel 38 generally includes a body including annular
outer wall 72 with outer surface 74, and annular inner wall 76
disposed radially inwardly of outer wall 72 and including an inner
surface 78 defining a central opening through mandrel 38. Rear wall
80 connects outer wall 72 and inner wall 76, is annular in shape,
and has a concave profile, as shown in FIG. 4. Inner mandrel 38
additionally includes an annular cavity 82 defined between outer
wall 72, inner wall 76, and rear wall 80 which opens toward the
front side of mandrel 38 opposite rear wall 80.
[0040] As shown in FIG. 4, gasket 34 and mandrels 36 and 38 have a
common longitudinal axis L.sub.1-L.sub.1 and, as described further
below, outer surfaces 62 and 74 of mandrels 36 and 38 are aligned
parallel to longitudinal axis L.sub.1-L.sub.1, or are aligned
substantially parallel to longitudinal axis L.sub.1-L.sub.1 whereby
outer surfaces 62 and 74 are angled slightly with respect to
longitudinal axis L.sub.1-L.sub.1.
[0041] When gasket 34 is in its folded position as shown in FIG. 4,
main body portion 40, intermediate portion 42, and sealing portion
44 of gasket 34 may be enclosed within cavities 70 and 82 of
mandrels 36 and 38, respectively, as shown in FIG. 5. Specifically,
the folded gasket 34 is placed within cavities 70 and 82 of
mandrels 36 and 38, and mandrels 36 and 38 are moved toward one
another until inner walls 64 and 76 thereof contact one another as
shown in FIG. 5. In this position, main body portion 40,
intermediate portion 42, and pipe sealing portion 44 of gasket 34
are completely enclosed or encapsulated within cavities 70 and 82
of mandrels 36 and 38 to prevent liquid concrete from contacting
the foregoing portions of gasket 34 during casting of gasket 34
within a concrete structure. Further, as shown in FIGS. 4 and 5,
the inner edges of outer walls 60 and 72 of mandrels 36 and 38 are
received within undercuts 52 in anchor flange 46 of gasket 34 to
provide an interlock between mandrels 36 and 38 and anchor flange
46 which further prevents liquid concrete from contacting main body
portion 40, intermediate portion 42, and pipe sealing portion 44 of
gasket 34. With the foregoing interlocking arrangement between the
inner edges of outer walls 60 and 72 of mandrels 36 and 38 and
undercuts 52 in anchor flange 46, at least some of main body
portion 40, intermediate portion 42, and pipe sealing portion 44 of
gasket 34 need not be enclosed within cavities 70 of mandrels 36
and 38 to prevent same from being contacted by liquid concrete
during casting. Anchor flange 46 of gasket 34 is exposed externally
of mandrels 36 and 38 for embedment within the cast concrete.
[0042] As shown in FIG. 5, outer surfaces 62 and 74 of outer walls
60 and 72 of mandrels 36 and 38, respectively, are disposed
parallel to the common longitudinal axis L.sub.1-L.sub.1 of gasket
34 and mandrels 36 and 38, or at a slight angle with respect to
longitudinal axis L.sub.1-L.sub.1. Specifically, outer surfaces 62
and 74 of first and second mandrels 36 and 38 are disposed
co-linear with a line L.sub.2-L.sub.2 parallel with longitudinal
axis L.sub.1-L.sub.1, or alternatively, are disposed at angles
A.sub.1 and A.sub.2, respectively, with respect to longitudinal
axis L.sub.1-L.sub.1. Angles A.sub.1 and A.sub.2 may be small as
0.5.degree., more preferably 1.2.degree., most preferably
1.5.degree., from line L.sub.2-L.sub.2, or angles A.sub.1 and
A.sub.2 may be as great as 7.degree., more preferably 4.degree.,
most preferably 2.degree., from line L.sub.2-L.sub.2. The inner
surfaces 66 and 78 of inner walls 64 and 76 of mandrels 36 and 38,
respectively, may or may not be aligned parallel with longitudinal
axis L.sub.1-L.sub.1.
[0043] When gasket 34 is enclosed within mandrels 36 and 38 as
shown in FIG. 5, the gasket and mandrel assembly 32 may be secured
in a suitable manner between a pair of curved outer and inner form
walls (not shown). The curved form walls fit against the convex
front wall 68 of mandrel 36 and against the convex rear wall 80 of
mandrel 38 in a concrete-tight manner. Thereafter, liquid concrete
is poured between the form walls around gasket and mandrel assembly
32. As shown in FIG. 5, after the concrete cures, anchor flange 46
of gasket 34 is embedded within the cured concrete to anchor gasket
34 within the resulting opening 84 of the curved wall 86 of the
concrete structure which is formed by the cured concrete.
[0044] Referring to FIG. 6, after the concrete cures and the form
walls are removed, mandrels 36 and 38 may be removed from the
opening 84 formed within wall 86 of the concrete structure by
pulling mandrels outwardly from opening 84 in opposite directions
along longitudinal axis L.sub.1-L.sub.1. Notably, a very slightly
angled orientation between outer surfaces 62 and 74 of mandrels 36
and 38 with respect to longitudinal axis L.sub.1-L.sub.1 as
discussed above facilitates the easy removal of mandrels 36 and 38
from opening 84 to reveal first and second circular inner surfaces
88 and 90 of opening 84 which are disposed on respective opposite
sides of anchor flange 46 of gasket 34. First and second circular
inner surfaces 88 and 90 of opening 84 are formed by outer surfaces
62 and 74 of mandrels 36 and 38, and are therefore disposed either
parallel to longitudinal axis L.sub.1-L.sub.1, or at the same
angles A.sub.1 and A.sub.2 with respect to longitudinal axis
L.sub.1-L.sub.1 as are outer surfaces 62 and 74 of mandrels 36 and
38. If an outer surface 62 or 74 of mandrel 36 or 38 is disposed
parallel with longitudinal axis L.sub.1-L.sub.1, it may be
advantageous to form the annular body of the mandrel with a
removable section or wedge which, when inserted into a gap in the
annular body of the mandrel, forces the annular body of the mandrel
into a circular shape for casting. After the concrete cures
following casting, the removable section or wedge may be removed,
allowing the annular body of the mandrel to slightly collapse
radially inwardly in order to facilitate removal of the mandrel
from the opening in the concrete wall.
[0045] Referring to FIG. 7, after removal of mandrels 36 and 38,
gasket 34 may be unfolded to its unfolded or extended position, and
a pipe 92 may be inserted through gasket 34. Thereafter, a clamping
band 94 is positioned within clamping band seat 56 of pipe sealing
portion 44 of gasket 34, and is then radially tightened to
sealingly compress sealing portion 44 and sealing ridges 58 of
gasket 34 into fluid tight engagement with outer surface 96 of pipe
92, thereby providing a fluid tight seal between pipe 92 and wall
86 of the concrete structure.
[0046] Additionally, as shown in FIG. 7, a first annular space or
gap 98 is formed between gasket 34 and pipe 92, and a second
annular space or gap 100 is formed between gasket 34 and opening 84
in wall 86. These gaps 98 and 100 provide take-up spaces which
accommodate flexing of gasket 34 to in turn accommodate angular
tilting movement of pipe 92 from longitudinal axis L.sub.1-L.sub.1
if pipe 92 should shift position with respect wall 86 of the
concrete structure after installation. If pipe 92 moves in a
tilting manner from longitudinal axis L.sub.1-L.sub.1, clamping
band 94 maintains fluid tight engagement between pipe sealing
portion 44 of gasket 34 and pipe 92.
[0047] If gasket 34 needs to be replaced due to failure of gasket
34 or any other reason, gasket 34 may be removed and replaced with
an expansion-type gasket in the manner shown in FIGS. 8 and 9.
Referring to FIG. 8, after clamping band 94 and pipe 92 have been
removed from gasket 34, gasket 34 may be removed from opening 84 in
wall 86 of the concrete structure by at least one of the following
two methods. First, as shown in the upper portion of FIG. 8, a
utility knife 102 or other suitable tool may be used to cut gasket
34 at the base of anchor flange 46 to thereby separate main body
portion 40 and the remainder of gasket 34 from anchoring flange 34.
Thereafter, gasket 34 is removed from opening 84 with anchor flange
46 remaining embedded within wall 86 of the concrete structure.
Alternatively, as shown in the lower portion of FIG. 8, when gasket
34 is formed of a material which is flexible enough to allow
sufficient deformation of anchor flange 46, anchor flange 46 of
gasket 34 may be pulled outwardly of wall 86 of the concrete
structure.
[0048] After removal of gasket 34, a second, expansion-type gasket
104 may be installed within opening 84 of the concrete structure as
follows. Gasket 104 is generally similar to gasket 34 described
above and may be made of the same material, and includes an annular
outer or wall sealing portion 106 having an outer surface and an
inner surface including expansion band seat 110. Gasket 104
additionally includes an annular inner or pipe sealing portion 112
which includes an outer surface having a clamping band seat 114 and
an inner surface. An intermediate portion 118 connects portions 106
and 112 of gasket 104.
[0049] An annular expansion band assembly, including expansion band
120 and an expanding device (not shown) are used to seal portion
106 of gasket 104 to one of circular inner surfaces 88 or 90 of
opening 84 within wall 86. Specifically, as shown in FIG. 9,
portion 106 of gasket 104 is fitted within opening 84 adjacent
first surface 88 of opening 84. Thereafter, an expansion band 120
is fitted within expansion band seat 110, and an expanding device
(not shown) is used to expand expansion band 120 outwardly to
sealingly compress portion 106 of gasket 104 into sealing
engagement with inner surface 88 of opening 84. Suitable expansion
bands and expanding devices are described in U.S. Pat. Nos.
5,507,500, 5,732,955, and 5,954,354, as well as in U.S. Patent
Application Publication No. 2004/0080118, each assigned to the
assignee of the present application, the disclosures of which are
expressly incorporated herein by reference. After gasket 104 has
been installed within opening 84 in wall 86, a clamping band 94 may
be used to sealingly compress portion 112 of gasket 104 into fluid
tight sealing engagement with outer surface 96 of pipe 92, as shown
in FIG. 9.
[0050] Advantageously, the angles A.sub.1 and A.sub.2 of circular
surfaces 88 and 90 of opening 84, which are parallel to or only
slightly angularly offset from longitudinal axis L.sub.1-L.sub.1 as
described above, provide surfaces to which a portion of an
expansion-type gasket may be sealingly compressed using an
expansion band assembly as described above. By contrast, in the
known arrangement shown in FIGS. 1 and 2, the inner surfaces of
opening 16 in wall 14 are angled from longitudinal axis
L.sub.1-L.sub.1 to a further extent, such that an expansion-type
gasket cannot be compressed against such surfaces. Therefore, as
described above, the present gasket and mandrel assembly 32
facilitates the formation of circular surfaces 88 and 90 of opening
84 at the angles discussed above, such that if the cast-in gasket
34 should fail or otherwise need to be replaced in the field,
gasket 34 may be removed from wall 86 of the concrete structure
followed by installation of an expansion-type gasket 104 without
necessitating repairs or re-casting of a portion or the entirety of
the concrete structure.
[0051] Referring to FIGS. 10-14, mandrel assembly 130 according to
another embodiment of the present invention is shown. Mandrel
assembly 130 is similar to mandrel assembly 32 described above, and
identical reference numerals will be used to indicate identical or
substantially identical structures therebetween. In particular,
mandrel assembly 130 of FIGS. 10-14 may be used with a cast-in type
gasket 34 described above or with other similar gaskets to cast
same within a wall of a structure. Referring to FIGS. 10-12, first
mandrel 132 and second mandrel 134 are shown. First mandrel 132 is
made at least in part of a relatively rigid material, for example a
rigid plastic such as polyethylene and polyvinyl chloride, and
generally includes a mandrel body 136 having first face 138,
annular outer surface 140, cavity 142, and inner section 144. First
face 138 is oriented substantially transversely to a longitudinal
axis L.sub.1-L.sub.1 of mandrel assembly 130 and first mandrel 132
and, similar to mandrel 36 described above, has a convex profile to
enable mandrel assembly 130 to be used to cast a gasket into a
curved wall of a structure. Referring to FIG. 12 and again,
similarly to mandrel assembly 32 described above, annular outer
surface 140 of first mandrel 132 is disposed at an angle A.sub.1
with respect to longitudinal axis L.sub.1-L.sub.1 and a line
L.sub.2 parallel to longitudinal axis L.sub.1-L.sub.1 which may be
as small as 0.5.degree., 0.75.degree., 1.degree., 1.25.degree.,
1.5.degree., 1.75.degree., or 2.degree., or may be as large as
7.degree., 6.degree., 5.degree., 4.degree., 3.degree., or
2.5.degree., for example. Cavity 142 of first mandrel 132 gasket is
a substantially annular cavity which faces toward second mandrel
134 along longitudinal axis L.sub.1-L.sub.1.
[0052] Referring to FIG. 12, body 136 of first mandrel 132 may be
formed of two separate components, including a first component 146
and second component 148 secured to one another via a plurality of
bolts 150 inserted through bores 152 in first component 146 and
threaded into threaded bores 154 of second component 148.
Additionally, a thread spring 156 may be disposed within cavities
defined within first and second components 146 and 148. Outer form
wall W.sub.O may be secured to first component 146 of first mandrel
132 via a bolt 158 passing through outer form wall W.sub.O and a
tapered passage 160 of first component 146 and threaded into thread
spring 156.
[0053] Referring to FIGS. 10-12, second mandrel 134 may be made at
least in part of a relatively resilient material, such as rubber or
a flexible plastic, for example, and generally includes second face
162 aligned substantially transversely to longitudinal axis
L.sub.1-L.sub.1 with second face 162 having a concave profile
similar to that of mandrel 38 described above such that first and
second mandrels 132 and 134 may be used to cast gasket 34 in a
curved wall of structure. Second mandrel 134 additionally includes
an annular outer surface 164 and an interior cavity 166 facing
cavity 142 of first mandrel 132 along longitudinal axis
L.sub.1-L.sub.1.
[0054] Referring to FIGS. 12 and 13, body 136 of first mandrel 132
may include an annular lip 168 which fits within or otherwise
engages an annular notch or groove 170 in second mandrel 134 to
temporarily locate and retain second mandrel 134 with respect to
first mandrel 132. Alternatively, first mandrel 132 may include an
annular notch or groove and second mandrel 134 may include an
annular lip.
[0055] Referring to FIG. 12, the folded gasket 34 is substantially
enclosed between the cooperating cavities 142 and 166 of first
mandrel 132 and second mandrel 134, respectively, in a manner
similar to mandrel assembly 32 described above, with anchoring
flange 46 of gasket 34 disposed exteriorly of mandrel assembly 130
for embedment within the cast concrete. Optionally, an annular
flange 172 of first mandrel 132 may engage cutout 50 of gasket 34
to aid in locating gasket 34 with respect to first mandrel 132 and
to prevent concrete from flowing interiorly into mandrel assembly
130 and contacting the interior portions of gasket 34. In one
embodiment, body 136 of first mandrel 132 may be inserted through
the folded gasket 34 such that the interior portions of gasket 34
are fitted within cavity 142 of first mandrel, followed by fitting
second mandrel 132 over body 136 of first mandrel 132 and engaging
lip 168 of first mandrel 132 with annular groove or notch 170 of
second mandrel 134 as described above.
[0056] Thereafter, mandrel assembly 130 is attached to outer form
wall W.sub.O as described above. In one embodiment, outer form wall
W.sub.O is mounted via a hinge (not shown) such that outer form
wall W.sub.O and mandrel assembly 130 may together be pivoted
upwardly to the vertical position shown in FIG. 12 to resiliently
press second mandrel 134 sealingly against an interior form wall
W.sub.I. Thereafter, concrete is filled between the outer and inner
form walls W.sub.O and W.sub.I and cures to embed anchor flange 46
of gasket 34 within the cured concrete. Alternatively, the
arrangement of first and second mandrels 132 and 134 may be
reversed, wherein first mandrel 132 is secured to interior form
wall W.sub.I and includes a concave face, and second mandrel is
pressed against outer form wall W.sub.O and includes a convex face,
for example. Further, first and second mandrels 132 and 134 may
have flat, planar faces for casting gaskets into flat, planar
walls.
[0057] Referring to FIG. 14, after inner form wall W.sub.I is
removed, second mandrel 134 may be removed from the cast concrete
by bending, twisting, or pulling same outwardly from the formed
opening 84 in the cured concrete, either by hand or with a suitable
tool. Advantageously, the resilient material from which second
mandrel 134 is made allows same to be easily deformed as necessary
to facilitate removal from the cured concrete. Thereafter, first
mandrel 132 may be slid outwardly from gasket 34, either along with
outer form wall W.sub.O or after outer form wall W.sub.O is
disengaged from first mandrel 132. Typically, it is easier to
remove second mandrel 134 prior to first mandrel 132, however,
first mandrel 134 may optionally be removed prior to second mandrel
134 in the manner described above
[0058] In a manner similar to mandrel assembly 32 described above,
outer annular surface 140 of first mandrel provides an annular
inner surface 88 in opening 84 of the cast wall which is disposed
at the same angle as outer annular surface 140 of first mandrel 132
with respect to longitudinal axis L.sub.1-L.sub.1, thereby enabling
a cast-in type gasket, such as gasket 34 or a similar gasket, to be
cast within the wall and wherein, should the cast-in gasket 34
fail, same may be removed from the wall and replaced with an
expansion-type or press-in gasket 104 as described above and shown
in FIGS. 7-9.
[0059] Referring to FIGS. 15 and 16, mandrel assembly 180 according
to another embodiment of the present invention is shown which, as
described below, may be configured for attachment to form walls
W.sub.O and W.sub.I (FIG. 12) via a bolt connection similar to
mandrel assembly 130, or via a magnetic connection. Mandrel
assembly 180 is similar to mandrel assemblies 32 and 130 described
above, and identical reference numerals will be used to indicate
identical or substantially identical structures therebetween.
Mandrel assembly 180 generally includes first mandrel 182 and a
second mandrel 134 identical to second mandrel 134 used with
mandrel assembly 130 described above.
[0060] First mandrel 182 is formed of two components, including
hollow main body portion 184 which may be formed of one or more
sections molded of a suitable plastic, for example, and annular
outer ring 186 including outer surface 140 identically configured
to outer surface of mandrel assembly 140 discussed above. Main body
portion 184 of first mandrel 182 generally includes a series of
walls including rear wall 188, front wall 190, outer wall 192
defining an annular cavity 194 for receipt of folded gasket 34, and
inner wall 196 defining a cylindrical interior cavity 198. Rear
wall 188 includes an inwardly-stepped portion 200 and a flange 201
having a series of threaded holes 202 along an outer periphery
thereof to which outer annular ring 186 is attached via a plurality
of fasteners 204.
[0061] Advantageously, the hollow construction of main body portion
184 of mandrel assembly 180 reduces the cost of manufacture
thereof, and also reduces the weight of mandrel assembly 180 as
compared to mandrel assembly 130 described above. Additionally,
main body portion 184 may be formed to any desired width to
accommodate varying spaces between form walls used for casting the
concrete structure, wherein the same outer annular ring 186 may be
used with differently-sized main body portions 184 to reduce the
total number of parts needed and thereby reduce the costs of
constructing first mandrels 182 of varying widths. Further, the
size, such as width and/or diameter, of either or both of second
mandrel 134 and annular outer ring 186 may be varied to provide
various sized openings in the structure while optionally using the
same size first mandrel 182. Also, the mandrels of all of the
mandrel assemblies disclosed herein may be shaped for use in
casting straight walls in addition to casting curved walls.
[0062] Similar to second mandrel 134 of mandrel assembly 130,
second mandrel 134 of mandrel assembly 180 is made of a resilient
material which may be sized such that, when mandrel assembly 180 is
disposed between a pair of form walls W.sub.O and W.sub.I (FIG. 12)
second mandrel 134 is resiliently compressed between the form walls
W.sub.O and W.sub.I to thereby provide an abutting seal against one
of the form walls to prevent concrete from penetrating into the
interior of mandrel assembly 180.
[0063] Main body portion 184 of mandrel assembly 180 may be
configured for bolt or magnetic attachment to a form wall in the
manner described below. For bolt attachment, as shown in FIG. 15,
bolt plate 206 is secured to inwardly-stepped portion 200 of rear
wall 188 of main body 184 via a plurality of threaded fasteners
208, and includes thread spring 156 to accommodate bolt 158 (FIG.
12) for connection to a form wall. Alternatively, or in addition
to, thread spring 156, as shown in FIG. 16, mandrel assembly 180
may include magnet assembly 210 fitted within into the hollow inner
space toward the front end of cylindrical interior cavity 198,
which is magnetically secured to the surface of a metal form wall
to position mandrel assembly 180 thereon.
[0064] In use, mandrel assembly 180 is used to cast an opening
within a concrete structure in the same manner as described above
with respect to mandrel assembly 130, and the outer annular surface
140 of outer annular ring 186 of mandrel assembly 180, again
similar to mandrel assembly 130, provides an annular inner surface
88 of opening 84 of the cast wall which is disposed at the same
angle of outer annular surface 140 of outer annular ring 186 with
respect to longitudinal axis L.sub.1-L.sub.1, thereby enabling a
cast-in type gasket, such as gasket 34 or a similar gasket, to be
cast within the wall and wherein, should the cast-in gasket 34
fail, same may be removed from the wall and replaced with an
expansion-type or press-in gasket 104 as described above and shown
in FIGS. 7-9.
[0065] While this invention has been described as having a
preferred design, the present invention can be further modified
within the spirit and scope of this disclosure. This application is
therefore intended to cover any variations, uses, or adaptations of
the invention using its general principles. Further, this
application is intended to cover such departures from the present
disclosure as come within known or customary practice in the art to
which this invention pertains and which fall within the limits of
the appended claims.
* * * * *