U.S. patent application number 12/855833 was filed with the patent office on 2012-02-16 for insulation product with inward curling closure flap.
Invention is credited to Derek Cooper Bristol, Monroe William Shumate.
Application Number | 20120037259 12/855833 |
Document ID | / |
Family ID | 45563922 |
Filed Date | 2012-02-16 |
United States Patent
Application |
20120037259 |
Kind Code |
A1 |
Shumate; Monroe William ; et
al. |
February 16, 2012 |
INSULATION PRODUCT WITH INWARD CURLING CLOSURE FLAP
Abstract
A pipe insulation product including a core of insulating
material and a laminate surrounding the core and bonded to the
core. The core may include an outer surface; an inner surface; and
a wall extending between the outer and inner surfaces. The laminate
may include a foil or metallized polymeric film sheet, a scrim, a
porous media sheet, and a polymeric film sheet bonded together via
an adhesive. The laminate may include a closure flap that is
configured to adhesively seal opposite ends of the laminate
together to form a cylindrical tube with the core enclosed therein.
The closure flap may be configured to include a curl that provides
a greater closure flap adhesive seal.
Inventors: |
Shumate; Monroe William;
(Littleton, CO) ; Bristol; Derek Cooper;
(Littleton, CO) |
Family ID: |
45563922 |
Appl. No.: |
12/855833 |
Filed: |
August 13, 2010 |
Current U.S.
Class: |
138/149 ;
29/428 |
Current CPC
Class: |
B32B 5/028 20130101;
Y10T 29/49826 20150115; B32B 2307/304 20130101; B32B 2307/736
20130101; B32B 27/065 20130101; B32B 2305/026 20130101; B32B
2317/122 20130101; B32B 2255/06 20130101; B32B 2255/10 20130101;
B32B 2255/205 20130101; F16L 59/14 20130101; B32B 37/144 20130101;
B32B 2307/7246 20130101; B32B 5/18 20130101; B32B 7/12 20130101;
B32B 15/12 20130101; B32B 27/12 20130101; B32B 29/02 20130101; B32B
38/1875 20130101; B32B 2305/08 20130101; B32B 7/06 20130101; B32B
15/14 20130101; B32B 1/08 20130101; B32B 2255/12 20130101; F16L
59/029 20130101; B32B 2597/00 20130101; B32B 15/046 20130101; B32B
2305/022 20130101; B32B 37/10 20130101; B32B 2250/05 20130101; B32B
3/266 20130101; B32B 38/1866 20130101; B32B 37/12 20130101; B32B
2255/02 20130101; F24F 13/0263 20130101; B32B 27/10 20130101; F16L
59/026 20130101; B32B 2305/38 20130101 |
Class at
Publication: |
138/149 ;
29/428 |
International
Class: |
F16L 9/14 20060101
F16L009/14; B23P 19/04 20060101 B23P019/04 |
Claims
1. A pipe insulation product comprising: a tubular core of
insulating material, the tubular core comprising: a length and a
longitudinal axis; a substantially cylindrical outer surface; a
substantially cylindrical inner surface; and a wall extending
between the cylindrical outer surface and the cylindrical inner
surface, the wall having a radially extending thickness and a slit
extending completely there through, the slit extending parallel to
the longitudinal axis of the tubular core for the length of the
tubular core; and a laminate that is roughly rectangular in shape
and that is coextensive with and bonded to the substantially
cylindrical outer surface of the tubular core and flexible so that
the tubular core and laminate can be opened, placed about a pipe,
and closed without degrading the laminate, wherein the laminate
comprises: a polymeric film sheet forming an outer exposed layer of
the laminate; a foil or metallized polymeric sheet material that
provides a fluid vapor barrier to minimize fluid vapor transmission
through the laminate; a scrim comprising a mesh of a plurality of
fibers; a porous media sheet; and an adhesive, wherein the adhesive
bonds the foil or metallized polymeric sheet material, the scrim,
the porous media sheet, and the polymeric film sheet together to
form the roughly rectangular laminate; wherein: the laminate
comprises a closure flap configured to seal opposite sides of the
laminate in a closed position so that the laminate forms a
substantially cylindrical tube with at least a portion of the
tubular core enclosed therein; and the closure flap is concave to
provide a greater closure flap seal.
2. The pipe insulation product of claim 1, wherein: the foil or
metallized polymeric film sheet forms an inner layer of the
laminate; the porous media sheet is positioned immediately adjacent
to the foil or metallized polymeric film sheet so that the foil or
metallized polymeric film sheet lies substantially flat against the
porous media sheet; and the configuration of the substantially flat
foil or metallized polymeric film sheet provides an improved perm
rating for the laminate.
3. The pipe insulation product of claim 1, wherein the closure flap
is configured to be concave by controlling an amount of tension in
the polymeric sheet material and controlling an amount of tension
in one or more of the other layers during lamination of the layers
so that, after lamination, the tension in the polymeric sheet
material is less than the tension in the one or more of the other
layers.
4. The pipe insulation product of claim 1, wherein the closure flap
is configured to be concave by: securing the closure flap in the
closed position; heat treating the laminate to soften the polymeric
sheet material; and cooling the polymeric sheet material so that
the polymeric sheet material hardens with the concave closure
flap.
5. The pipe insulation product of claim 1, wherein the closure flap
is configured to be concave by: arranging at least one laminate so
that the closure flap is positioned in the closed position; and
maintaining the laminate with the closure flap in the closed
position for a period of time, wherein after the period of time
shape memory is induced in the closure flap.
6. The pipe insulation product of claim 1, wherein the closure flap
is configured to be concave by positioning the scrim between the
porous media material and the polymeric sheet material to either:
provide improved control over the tensioning of one or more of the
polymeric sheet material, the porous medial material, and the foil
or metallized polymeric sheet material; or provide increased
stability to the polymeric sheet material.
7. The pipe insulation product of claim 1, wherein the closure flap
is configured to be concave by either: controlling the temperature
of an adhesive used to bond the laminate and tubular core to
minimize heat dissipation from the adhesive to the polymeric sheet
material; or cooling the tubular core of insulating material to
roughly ambient temperature prior to bonding the tubular core and
the laminate to minimize heat dissipation from the insulating
material to the polymeric sheet material.
8. The pipe insulation product of claim 1, wherein the closure flap
is configured to be concave by either: controlling the size and
configuration of the fibers of the scrim fiber mesh to reduce a
convex configuration of the closure flap; or configuring the scrim
fiber mesh to include one or more fibers configured to provide the
closure flap with the concave configuration.
9. The pipe insulation product of claim 1, wherein the porous media
sheet comprises a kraft paper between the range of 25 and 35 pounds
per 3000 square feet to further provide a greater closure flap seal
by increasing the flexibility of the laminate.
10. A method for producing a roughly rectangular laminate that
provides a greater laminate seal, the method comprising: providing
a foil or metallized polymeric sheet material, the foil or
metallized polymeric sheet material forming an inner layer of the
laminate that provides a fluid vapor barrier to minimize fluid
vapor transmission through the laminate, the foil or metallized
polymeric sheet material comprising: a length, a width, a first
face, and a second face, wherein the length and width form an area
that define the first face and the second face; providing a
polymeric sheet material, wherein the polymeric sheet material is
coextensive with the second face and the polymeric sheet material
forms an outer exposed layer of the laminate; providing an
intermediate layer disposed between the foil or metallized
polymeric sheet material and the polymeric sheet material, wherein
the intermediate layer provides reinforcement for the laminate;
bonding, via an adhesive material, the foil or metallized polymeric
sheet material, the scrim, the porous media sheet material, and the
polymeric sheet material together to form the laminate jacket,
wherein the laminate jacket comprises a closure flap configured to
seal opposite sides of the laminate jacket in a closed position so
that the laminate jacket forms a hollow cylindrical tube; and
subjecting the closure flap to one or more processes to reshape the
closure flap so that after the one or more processes, the closure
flap is radially closer to the outer surface of the laminate to
provide a greater adhesive seal.
11. The method for producing a laminate jacket as in claim 10, the
method further comprising: positioning a tubular core of insulating
material directly adjacent the first face of the foil or metallized
polymeric sheet material, wherein the tubular core comprises: a
length and a longitudinal axis; a substantially cylindrical outer
surface, the substantially cylindrical outer surface comprising a
surface area that is roughly equivalent to the area of the first
face; a substantially cylindrical inner surface; and a wall
extending between the cylindrical outer surface and the cylindrical
inner surface; the wall comprising: a radially extending thickness;
and a slit extending from the cylindrical outer surface to the
cylindrical inner surface and extending parallel to the
longitudinal axis of the tubular core for the length of the tubular
core; and bonding, via an adhesive material, the tubular core of
insulating material with the first face of the foil or metallized
polymeric sheet material, wherein the laminate and tubular core are
flexible so that the tubular core and laminate jacket can be
opened, placed about a pipe, and closed without degrading the
laminate jacket.
12. The method for producing a laminate jacket as in claim 10,
wherein subjecting the closure flap to one or more processes
comprises either: reducing a convex configuration of the closure
flap, or configuring the closure flap to include a concave
configuration.
13. The method for producing a laminate jacket as in claim 10,
wherein subjecting the closure flap to one or more processes
comprises controlling an amount of tension in the polymeric sheet
material and controlling an amount of tension in one or more of the
other layers during lamination of the layers so that, after
lamination, the tension in the polymeric sheet material is less
than the tension in the one or more of the other layers.
14. The method for producing a laminate jacket as in claim 10,
wherein subjecting the closure flap to one or more processes
comprises: securing the closure flap in the closed position; heat
treating the laminate to soften the polymeric sheet material; and
cooling the polymeric sheet material so that the polymeric sheet
material hardens with the closure flap curled toward the closed
position.
15. The method for producing a laminate jacket as in claim 11,
further comprising: flexing the tubular core and laminate jacket to
open the laminate jacket and tubular core; placing the laminate
jacket and tubular core about the pipe; and closing the laminate
jacket and tubular core about the pipe by applying pressure to the
closure flap to adhesively seal the opposite sides of the laminate
jacket.
16. A method for producing a roughly rectangular laminate that
provides a greater laminate seal, the method comprising: providing
a foil or metallized polymeric sheet material, the foil or
metallized polymeric sheet material forming an inner layer of the
laminate that provides a fluid vapor barrier to minimize fluid
vapor transmission through the laminate, the foil or metallized
polymeric sheet material comprising: a length, a width, a first
face, and a second face, wherein the length and width form an area
that define the first face and the second face; providing a
polymeric sheet material, wherein the polymeric sheet material is
coextensive with the second face and the polymeric sheet material
forms an outer exposed layer of the laminate; providing a scrim
comprising a mesh of a plurality of fibers, wherein the scrim is
substantially coextensive with the second face; providing a porous
media sheet material, wherein: the scrim and porous media sheet
material are positioned between the foil or metallized polymeric
film sheet and the polymeric film sheet, and the porous media sheet
material is substantially coextensive with the second face;
bonding, via an adhesive material, the foil or metallized polymeric
sheet material, the scrim, the porous media sheet material, and the
polymeric sheet material together to form the laminate jacket,
wherein the laminate jacket comprises a closure flap configured to
seal opposite sides of the laminate jacket in a closed position so
that the laminate jacket forms a hollow cylindrical tube; and
subjecting the closure flap to one or more processes to reshape the
closure flap so that after the one or more processes, the closure
flap is radially closer to the outer surface of the laminate to
provide a greater adhesive seal.
17. The method for producing a laminate jacket as in claim 16,
wherein subjecting the closure flap to one or more processes
comprises controlling an amount of tension in the polymeric sheet
material and controlling an amount of tension in one or more of the
other layers during lamination of the layers so that, after
lamination, the tension in the polymeric sheet material is less
than the tension in the one or more of the other layers.
18. The method for producing a laminate jacket as in claim 16,
wherein subjecting the closure flap to one or more processes
comprises: securing the closure flap in the closed position; heat
treating the laminate to soften the polymeric sheet material; and
cooling the polymeric sheet material so that the polymeric sheet
material hardens with the closure flap in a concave
configuration.
19. The method for producing a laminate jacket as in claim 16,
wherein subjecting the closure flap to one or more processes
comprises: arranging at least one laminate so that the closure flap
is positioned in the closed position; and maintaining the laminate
with the closure flap in the closed position for a period of time,
wherein after the period of time shape memory is induced in the
closure flap.
20. The method for producing a laminate jacket as in claim 16,
wherein the foil or metallized polymeric film sheet forms an inner
layer of the laminate; the porous media sheet is positioned
immediately adjacent to the foil or metallized polymeric film sheet
so that the foil or metallized polymeric film sheet lies
substantially flat against the porous media sheet; and the
configuration of the substantially flat foil or metallized
polymeric film sheet provides an improved perm rating for the
laminate.
Description
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This application is related to the following Non-Provisional
U.S. patent applications: U.S. patent application Ser. No. ______
(attorney Docket No. 7983) filed on Aug. 13, 2010 by Shumate,
entitled "Systems and Methods for Insulating a Pipe;" U.S. patent
application Ser. No. ______ (attorney Docket No. 7981) filed on
Aug. 13, 2010 by Shumate et al., entitled "Pipe Insulation Product
with Charge Dissipater;" and U.S. patent application Ser. No.
______ (attorney Docket No. 7984) filed on Aug. 13, 2010 by Shumate
et al., entitled "Pipe Insulation Products and Methods."
[0002] The entire disclosures of all of the aforementioned
Non-Provisional U.S. patent applications are hereby incorporated by
reference, for all purposes, as if fully set forth herein.
BACKGROUND OF THE INVENTION
[0003] The subject invention relates generally to pipe insulation
products and more specifically to pipe insulation products
comprising an insulating material core enclosed within a laminate
jacket.
[0004] Piping is often used to transport one or more fluids between
destinations. For example, piping may be used to transport water,
petroleum, oxygen, etc. The piping is often made from a metal
material, such as copper, stainless steel, galvanized steel,
aluminum, brass, titanium, etc., or from a plastic material, such
as polyvinyl chloride (PVC), chlorinated polyvinyl chloride (CPVC),
fiber reinforced plastic (FRP), polypropylene (PP), polyethylene
(PE), etc. Piping may also be made from a ceramic, fiberglass, or
concrete material, although these pipes are less common.
[0005] During fluid transportation, the fluid may be subjected to
heating and/or cooling from the surrounding environment. For
example, the fluid may be transported in either a hot or cold state
relative to the surrounding environment, which induces heat
transfer to or from the fluid and pipes. HVAC systems are a common
example of systems that routinely utilize various pipe
configurations to transport hot or cold fluids. Due to the
conductive nature of the pipes (especially metal pipes), heat may
be conducted to or from the fluid during transportation. The
addition or removal of heat may result in the decreased efficiency
of a system and/or increased time and/or expense in operating the
system. For example, in HVAC systems, the addition of heat to
cooled fluids may result in loss of efficiency for a cooling unit
and may also result in increased expense because of increased
operating time and energy needed to achieve a desired cooling
level.
[0006] To reduce heat transfer during fluid transportation, pipe
insulation products are commonly installed on one or more sections
of pipes to retard the flow of heat to or from the pipes. Commonly,
one or more sections of pipe are fitted with a pipe insulation
product where the sections of pipe are generally fully encased
within the pipe insulation product. Separate sections of the pipe
insulation product are often coupled together via adhesive tapes.
The outer surface of the pipe insulation product is often designed
to enhance the visual appeal of the piping system and serve as a
means for sealing the pipe insulation product about the pipes of
the piping system. In addition, the various layers of the pipe
insulation product often serve one or more important functions
(e.g., restricting water vapor transmission; resisting mold, mild,
and/or fungal growth; providing puncture resistance, tensile
strength, and/or durability; resisting UV, handling, environmental,
and/or shipping damage, etc.).
[0007] To perform some of these functions, it is critical that the
outer layer of the pipe insulation product be sealed and remain
sealed over the life of the pipe insulation product. For example,
the pipe insulation product may include one or more layers that
restrict the transmission of water vapor or other environmental
contaminants through the laminate. Generally, a pipe insulation
product is required to have a water vapor transmission rate of no
greater than 0.02 perms. If the pipe insulation product is not able
to seal and/or remain sealed over the life of the product, the
layer that functions as a water vapor barrier or retarder may be
compromised or circumvented because water vapor and/or other
contaminants may freely flow through the unsealed portion of the
pipe insulation product.
[0008] Leakage of water vapor and/or other contaminants into the
pipe insulation product's interior may cause a variety of problems
for the insulated pipe and/or surrounding objects including:
condensation of water on the pipes; mold, mildew, or fungal growth;
pipe corrosion or degradation; staining of the pipe insulation
product and/or surrounding objects; water drip damage; loss of the
pipe insulation product's insulating value, etc. Hence, the
integrity of the pipe insulation product's seal is critically
important to the functionality of the pipe insulation product.
BRIEF SUMMARY OF THE INVENTION
[0009] One embodiment of the present invention may include a pipe
insulation product for insulating a pipe. The pipe insulation
product may include a tubular core of insulating material and a
laminate that is roughly rectangular in shape, that is and bonded
to the tubular core, and that is flexible so that the tubular core
and laminate can be opened, placed about a pipe, and closed without
degrading the laminate.
[0010] The tubular core may include a length and a longitudinal
axis; a substantially cylindrical outer surface; a substantially
cylindrical inner surface; and a wall extending between the
cylindrical outer surface and the cylindrical inner surface. The
wall may include a radially extending thickness and a slit that
extends completely through the wall from the outer surface to the
inner surface and that extends parallel to the longitudinal axis of
the tubular core for the length of the tubular core.
[0011] The laminate may include a polymeric film sheet that forms
an outer exposed layer of the laminate; a foil or metallized
polymeric sheet material that provides a fluid vapor barrier to
minimize fluid vapor transmission through the laminate; a scrim
comprising a mesh of a plurality of fibers; a porous media sheet;
and an adhesive that bonds the foil or metallized polymeric sheet
material, the scrim, the porous media sheet, and the polymeric film
sheet together to form the roughly rectangular laminate.
[0012] The laminate may also include a closure flap that is
configured to adhesively seal opposite sides of the laminate in a
closed position so that the laminate forms a substantially
cylindrical tube with at least a portion of the tubular core
enclosed therein. The closure flap may be configured to include a
curl that provides a greater closure flap adhesive seal bond. The
porous media sheet may include a kraft paper between the range of
25 and 35 pounds per 3000 square feet to provide a greater closure
flap adhesive seal bond by increasing the flexibility of the
laminate.
[0013] Configuring the closure flap to include a curl may comprise
either reducing an amount of curl already present in the closure
flap, where the present curl is a curling of the closure flap away
from the closed position (i.e., reverse curl); or may include
configuring the closure flap to curl toward the closed position.
Configuring the closure flap to include a curl may also comprise
controlling an amount of tension in the polymeric sheet material
and an amount of tension in one or more of the other layers during
lamination of the layers so that, after lamination, the tension in
the polymeric sheet material is less than the tension in the one or
more of the other layers. Configuring the closure flap to include a
curl may further comprise securing the closure flap in the closed
position, heat treating the laminate to soften the polymeric sheet
material, and cooling the polymeric sheet material so that the
polymeric sheet material hardens with the closure flap curled
toward the closed position.
[0014] Configuring the closure flap to include a curl may
additionally comprise arranging at least one laminate so that the
closure flap is positioned in the closed position and maintaining
or holding the laminate with the closure flap in the closed
position for a period of time so that, after the period of time,
shape memory is induced in the closure flap. Configuring the
closure flap to include a curl may additionally comprise
positioning the scrim between the porous media material and the
polymeric sheet material to either provide improved control over
the tensioning of one or more of the polymeric sheet material, the
porous medial material, and the foil or metallized polymeric sheet
material; or to provide increased stability to the polymeric sheet
material.
[0015] Configuring the closure flap to include a curl may
additionally comprise either controlling the temperature of an
adhesive used to bond the laminate and tubular core to minimize
heat dissipation from the adhesive to the polymeric sheet material;
or cooling the tubular core of insulating material to roughly
ambient temperature prior to bonding the tubular core and the
laminate to minimize heat dissipation from the insulating material
to the polymeric sheet material. Configuring the closure flap to
include a curl may additionally comprise either controlling the
size and configuration of the fibers of the scrim fiber mesh to
reduce a curl of the closure flap away from the closed position; or
configuring the scrim fiber mesh to include one or more fibers
configured to provide the closure flap with a positive curling
force toward the closed position.
[0016] Another embodiment of the present invention may include a
method for producing a roughly rectangular laminate that provides a
greater laminate seal. The method may include providing a foil or
metallized polymeric sheet material that forms an inner layer of
the laminate and that provides a fluid vapor barrier to minimize
fluid vapor transmission through the laminate. The method may also
include providing a polymeric sheet material that is coextensive
with the foil or metallized polymeric sheet material and that forms
an outer exposed layer of the laminate. The method may further
include providing a scrim comprising a mesh of a plurality of
fibers where the scrim is coextensive with the foil or metallized
polymeric sheet material. The method may additionally include
providing a porous media sheet material.
[0017] The porous media sheet material may be coextensive with the
foil or metallized polymeric film sheet. The scrim and porous media
sheet material may be positioned between the foil or metallized
polymeric film sheet and the polymeric film sheet. The method may
additionally include bonding the foil or metallized polymeric sheet
material, the scrim, the porous media sheet material, and the
polymeric sheet material together with an adhesive to form the
laminate jacket. The laminate jacket may include a closure flap
that is configured to adhesively seal opposite sides of the
laminate jacket in a closed position so that the laminate jacket
forms a hollow cylindrical tube. The method may additionally
include configuring the closure flap to include a curl that
provides a greater closure flap adhesive seal bond.
[0018] The method for producing a laminate jacket may additionally
include bonding a tubular core of insulating material with the
laminate jacket. The method for bonding the tubular core and
laminate jacket may include positioning a tubular core of
insulating material directly adjacent to the foil or metallized
polymeric sheet material. The method may also include bonding the
tubular core of insulating material with the foil or metallized
polymeric sheet material with an adhesive material. The laminate
and tubular core may be flexible so that the tubular core and
laminate jacket can be opened, placed about a pipe, and closed
without degrading the laminate jacket. The method may further
include flexing the tubular core and laminate jacket to open the
laminate jacket and tubular core; placing the laminate jacket and
tubular core about the pipe; and closing the laminate jacket and
tubular core about the pipe by applying pressure to the closure
flap to adhesively seal the opposite sides of the laminate
jacket.
[0019] Another embodiment of the present invention may include a
roughly rectangular laminate. The laminate may include a polymeric
film sheet forming an outer exposed layer of the laminate; a foil
or metallized polymeric sheet material the provides a fluid vapor
barrier to minimize fluid vapor transmission through the laminate;
a scrim comprising a mesh of a plurality of fibers; a porous media
sheet; and an adhesive that bonds the foil or metallized polymeric
sheet material, the scrim, the porous media sheet, and the
polymeric film sheet together to form the roughly rectangular
laminate. The laminate may include a closure flap that is
configured to adhesively seal opposite sides of the laminate in a
closed position so that the laminate forms a substantially
cylindrical tube. The closure flap may be configured to curl toward
the closed position to provide a greater closure flap adhesive seal
bond.
[0020] The foil or metallized polymeric film sheet may form an
inner layer of the laminate and the porous media sheet may be
positioned immediately adjacent to the foil or metallized polymeric
film sheet so that the foil or metallized polymeric film sheet lies
substantially flat against the porous media sheet. The
configuration of the substantially flat foil or metallized
polymeric film sheet may provide an improved perm rating for the
laminate.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] FIG. 1 is a schematic perspective view of a pipe insulation
product that includes a core of insulating material encased within
a laminate jacket.
[0022] FIG. 2 is a schematic perspective view of a laminate jacket
according to one embodiment of the present invention with portions
of the laminate broken away to show the various layers of the
laminate.
[0023] FIG. 3 is a schematic perspective view of a process for
manufacturing a laminate.
[0024] FIG. 4 is a schematic perspective view illustrating a
process for inducing an inward curling closure flap.
[0025] FIG. 5 is a schematic perspective view illustrating another
process for inducing an inward curling closure flap.
[0026] FIG. 6 is a schematic perspective view illustrating
laminates of the present invention having different layer
configurations.
[0027] FIG. 7 is a schematic perspective view of various scrim
fibers that may be used to induce an inward curling closure
flap.
[0028] FIG. 8 is a flow diagram illustrating a method for
manufacturing a pipe insulation product.
DETAILED DESCRIPTION OF THE INVENTION
[0029] The present invention includes a pipe insulation product
that may be used to insulate a pipe and to provide one or more
other beneficial properties. For example, the pipe insulation
product may serve an aesthetic purpose when fitted about pipe
sections. Pipe insulation products are often designed to provide a
smooth, finished, and visually appealing outer surface to enhance
the visual appeal of the piping systems. In addition, the pipe
insulation product may also shield or protect the pipe from one or
more environmental elements (e.g., water vapor). The
protection/shielding function minimizes potential risks for the
pipe and/or for surrounding objects (e.g., minimizes condensation
of water on the pipes; mold, mildew, and/or fungal growth; water
drip damage; loss of the pipe insulation product's insulating
value; etc.). To minimize these risks, it is critical that the
outer layer of the pipe insulation product be sealed and remain
sealed over the life of the pipe insulation product. Further, the
pipe insulation product must readily adapt to a wide variety of
different climates and conditions in which the products are often
used and/or installed (e.g., hot, cold, humid, dry, etc.).
[0030] Pipe insulation products typically include a tubular core of
insulating material surrounded by and encased within a laminate
jacket or laminate. Individual segments of the pipe insulation
product typically range in length from about 36 inches to about 48
inches; have a wall thickness ranging from about 0.5 inches to
about 3 inches; and a range in outside diameter from about 2 inches
to about 32 inches.
[0031] In addition, the laminate may include one or more layers
that provide various beneficial properties that enhance the
performance of the pipe insulation product. For example, one of the
most important functions that the laminate serves is to act as a
water vapor barrier to protect the pipe and/or insulating material
from water vapor in the surrounding environment. Water vapor that
is able to pass into the laminate's interior may condensate on the
pipes and/or absorb into the insulating material, which may cause
pipe corrosion or degradation; mold, mildew, and/or fungal growth;
water drip damage; staining of the laminate and/or surrounding
objects; loss of the pipe insulation product's insulating value;
etc.
[0032] To provide the water vapor barrier function, laminates
typically include an aluminum foil layer that reduces the
transmission of water vapor and/or other contaminants through the
laminate. In addition, laminates typically include a closure flap
and adhesive material that allows the ends or edges of the laminate
to be sealed in a closed position so that the laminate forms a
sealed hollow tube fully encasing the pipe and insulating material
(the unsealed laminate allows the laminate and tubular core to be
opened and placed about a pipe). The failure of the closure flap to
seal and/or remain sealed may compromise or circumvent the
laminate's water/contaminant barrier function because water vapor
and/or other contaminants may freely flow through the unsealed
portion of the laminate into the interior.
[0033] In some instance, the configuration of the pipe insulation
product may contribute to the inability of the closure flap to seal
and/or remain sealed. For example, some laminate jackets include a
polymeric film material outer layer. The polymeric film material
may be selected as the outer layer to provide one or more
advantages including: durability, wrinkle resistance, stain
resistance, mold resistance, aesthetic appeal, etc. However, the
closure flap of laminates that include a polymeric film outer layer
may have a tendency to curl away from the sealing position, or in
other words "reverse curl" (i.e., the closure flap may curl away
from the position it occupies when the laminate is closed or
sealed). The reverse curl of the closure flap may impart a lifting
force on the adhesive material that seals the laminate, which may
facilitate in failure of the seal. In addition, the inclusion of
the polymeric film material outer layer may increase the stiffness
and rigidity of the laminate, which may impede the ability of the
closure flap to be curled toward the sealing position and remain in
the sealing position. Further, the various different climates and
conditions that the pipe insulation product may be subjected to,
and therefore must adapt to, may increase the likelihood that the
closure flap's seal will fail.
[0034] The present invention provides a laminate with closure flap
having a reduced "reverse curl," or in some embodiments provides a
laminate with a closure flap having a "positive curl" where the
closure flap curls toward the sealing position (i.e., the closure
flap may curl toward the position it occupies when the laminate is
closed or sealed). A laminate with a reduced reverse curl or a
positive curl may increase the integrity of the closure flap seal
(i.e., may provide for a greater closure flap adhesive seal bond)
by reducing a lifting force and/or imparting a closure force (i.e.,
a force biasing the closure flap toward the closed position).
Additionally, the reduced reverse curl and/or positive curl may
increase the integrity of the seal, and hence reduce the seal's
failure rate, over a wide variety of different climates and
conditions to which the pipe insulation product may be exposed. In
other words, the present invention may allow a single pipe
insulation product to be used in a variety of conditions because of
the product's increased ability to maintain a closed sealed
position in all conditions. These and other advantages of the
present invention will become more evident with reference to the
figures.
[0035] As shown in FIG. 1, a pipe insulation product 100 may
include a tubular core of insulating material 104 that may include
a substantially cylindrical outer surface (i.e., the outside of the
tubular core that directly contacts the laminate) and a
substantially cylindrical inner surface 114. Extending between the
cylindrical outer surface and the cylindrical inner surface 114 may
be a wall of insulating material. The insulating material provides
the insulating properties of the pipe insulation product 100. In
one embodiment, the insulating material may be a fibrous material
(e.g., fiberglass, mineral wool, refractory ceramic fiber, chopped
strand fiber glass, etc.). In other embodiments the insulating
material may be a foam (e.g., phenolic foam, polyisocyanurate,
polyolefin, polystyrene, polyurethane), a polymer, foam glass,
microporous insulation (e.g., Microtherm.RTM.), or any other
material that provides insulation.
[0036] The cylindrical inner surface 114 may be configured to
correspond with a specific pipe outer diameter (e.g., 1/2 inch, 1
inch, etc.). The tubular core 104 may also include a longitudinally
extending slit 112 that passes completely through the wall of
insulating material on one side and into the interior of the
substantially cylindrical inner surface 114 so that the tubular
core 104, and thus, the pipe insulation product 100, can be opened,
passed over, and closed about a pipe.
[0037] Circumferentially surrounding and encasing the tubular core
104 is a laminate jacket or simply a laminate 102. The laminate 102
has a thickness 106 that includes one or more layers of various
materials as described below. The laminate 102 is roughly
co-extensive with the tubular core 104 and bonded to the
cylindrical outer surface. The laminate 102 may be positioned so
that a longitudinal edge portion 116 extends parallel and adjacent
to the slit 112, but does not overlap the slit 112. The laminate
102 includes a closure flap 108 that may have a pressure sensitive
adhesive layer 110 so that the laminate 102 may be adhesively
sealed in a closed position fully encasing the tubular core 104
within the laminate 102. The laminate may be sealed by folding or
overlapping the closure flap 108 over the longitudinal edge portion
116 of the laminate 102 and by applying pressure to the pressure
sensitive adhesive layer 110 so that the closure flap 108
adhesively seals to the outer surface of the overlapped portion of
the laminate 102.
[0038] In some embodiments, the closure flap 108 may curl outward,
meaning that the closure flap 108 curls away from the closed
position (FIG. 1 shows the outward or "reverse" curl of the closure
flap 108). In such embodiments, the outward or reverse curl must be
overcome in order to adhesively seal the closure flap 108 to the
laminate's outer surface. The reverse curl of the closure flap 108
may impart a lifting force on the adhesive material after the
closure flap 108 is sealed, which may cause the closure flap 108 to
become unsealed at some time during the laminate's 102 lifetime
(i.e., the reverse curl may cause the closure flap 108 to peel back
away from the sealed position). The closure flap's tendency to
unseal or peel back may be enhanced under some environmental
conditions and/or may be enhanced as those conditions change (i.e.,
unsealing or peeling back may be accelerated due to high heat and
humidity, due to repeated change from high to low temperatures,
etc.). The reverse curl may be due to the stiffness of the porous
media layer; stiffness, shrinkage, and/or internal stress within
the polymeric film sheet layer; etc.
[0039] In other embodiments, the closure flap 108 may not have a
reverse curl, but may be biased toward a straight or flat position
due to the stiffness of the laminate and/or one or more layers of
the laminate (i.e., the porous media layer, the polymeric film
material, etc.). As additional layers are added to the laminate,
the stiffness may increase, which may cause and/or enhance the
closure flap 108 sealing problems discussed herein.
[0040] The closure flap 108 may include a removable silicone
treated release strip (not shown) removably adhered to the pressure
sensitive adhesive layer 110 to protect the adhesive material from
degradation prior to installation. Maintaining a sealed closed
position is a critical function of the closure flap 108 and
adhesive layer 110 so that the insulated pipe and/or insulating
material are not subjected to one or more environmental elements,
such as water vapor. If the closure flap 108 is not able to seal or
remain sealed (e.g., the closure flap 108 curls backward after
being adhered to the laminate's outer surface), then water vapor
and/or other contaminants may flow between the closure flap 108 and
longitudinal edge portion 116 and thereby leak or pass into the
interior of the pipe insulation product (i.e., pass to the encased
pipe and insulating material). Water vapor and/or other
contaminants that pass into the laminate's interior may cause
condensation of water on the pipes; pipe corrosion or degradation;
mold, mildew, and/or fungal growth; water drip damage; staining of
the laminate and/or surrounding objects; loss of the pipe
insulation product's insulating value; etc.
[0041] The laminate 102 may include one or more flame retardants,
fungi growth inhibiting agents, charge dissipators, and/or other
additives to enhance the performance of the laminate. Additionally,
butt strips (not shown) may be used to connect individual segments
of the pipe insulation product end to end. The butt strips may be
strips of adhesive material (i.e., tape) that are substantially
impermeable to fluid vapors to greatly restrict or eliminate the
transmission of water vapor through the butt strips (i.e., the butt
strips seal end segments of the pipe insulation product 100
together). The butt strip's ability to seal the end segments may
also be compromised due to the closure flap's tendency to peel back
or unseal.
[0042] FIG. 2 depicts a laminate jacket 200 according to one
embodiment of the present invention. FIG. 2 shows portions of the
laminate 200 broken away to reveal the various layers of the
laminate. The laminate 200 may include an inner layer composed of a
foil or metallized polymeric film sheet 208. Preferably, the
laminate 200 includes an inner layer that is made of aluminum foil
or metallized polyethylene terphthalate (MPET) between about 0.48
mils and about 100 mils in thickness (between about 48 and 100
gauge in thickness). The inner layer aluminum foil or MPET provides
a nearly impermeable fluid vapor barrier to fluids that are
external to and surrounding the pipe insulation product. For
example, the foil or metallized polymeric film sheet 208 is nearly
impermeable to water vapor, which protects the insulated pipe from
water condensation, corrosion, loss of insulating value, mold
growth, etc. The foil or metallized polymeric film sheet 208
enables the laminate 200 to provide a water vapor transmission rate
of less than 0.02 perms.
[0043] By using the foil or metallized polymeric film sheet 208,
fluid may be passed through the insulated pipe and one or more
environmental elements (e.g., water vapor) in the surrounding
environment may be restricted (or kept) from penetrating through
laminate to the pipe. When cold fluid is passed through the pipe,
the foil or metallized polymeric film sheet 208 prevents water
vapor from condensing on the pipes and causing the associated
problems described herein. If the closure flap 108 becomes
unsealed, however, the water vapor barrier is circumvented as water
vapor may freely flow between the unsealed portion of the laminate.
Although the foil or metallized polymeric sheet 208 is described as
the inner layer of the laminate 200, the foil or metallized
polymeric sheet 208 may be positioned anywhere within the laminate
(e.g., immediately adjacent the polymeric sheet outer layer).
[0044] The laminate 200 may also include a scrim 206 the includes a
mesh of a plurality of fibers. The scrim 206 may function to
reinforce and strengthen the laminate 200 and thereby provide
increased tensile strength, puncture resistance, etc. The scrim 206
may be made of fiberglass reinforcing yarn, such as but not limited
to a G75 or H110 yarn. In addition, the yarn may be configured to
be from 2 to 6 strands per inch in both the machine and cross
machine directions, with a typical scrim being about 5 strands per
inch in both directions. In some embodiments the scrim 206 may be
made of polyester strings or any other synthetic string. The scrim
206 may be positioned immediately adjacent to the foil or
metallized polymeric sheet 208 or may positioned anywhere else
within the laminate (i.e., may be positioned immediately adjacent
the polymeric sheet outer layer 202).
[0045] The laminate 200 may also include a porous media sheet 204.
The porous media sheet 204 may be positioned immediately adjacent
to the scrim 204 or may be positioned anywhere else within the
laminate 200. The porous media sheet 204 may be a kraft paper that
is between about 25 and 45 pounds/3000 square feet and may include
one or more additives to enhance the performance of the laminate
200 (e.g., fire retardant additives and/or anti-microbial agents to
prevent mold or fungal growth and prevent propagation of smoke
and/or fire). In one embodiment, the porous media sheet 204 may be
a kraft paper between 25 and 35 pounds/3000 square feet to provide
increased seal integrity and/or closure of the closure flap 108
without significantly degrading beneficial properties of the
laminate (e.g., tensile strength, puncture resistance, handling
damage resistance, etc.). In one specific embodiment, the kraft
paper may be roughly 30 pounds/3000 square feet to provide optimal
levels of closure flap seal integrity and laminate properties.
[0046] Alternatively, the porous media sheet 204 may be other
materials such as a fiberglass mat, synthetic mat, paper, etc.
Likewise, in some embodiments the scrim 206 and porous media sheet
204 may be replaced by a single, preferably porous, material. The
porous nature of the porous media sheet 204 may allow absorption
and retention of one or more additives within the porous media
sheet layer, which may provide one or more enhancements to the
laminate 200 (e.g., flame and smoke propagation resistance; mold,
mildew, and/or fungal growth resistance; etc.).
[0047] In laminates that employ a kraft paper, the use of a heavy
weight kraft paper (e.g., 40-45 pounds/3000 square feet) may be
preferred because such papers provide several advantages over
lighter weight papers (e.g., 25-35 pounds/3000 square feet). For
example, heavier weight kraft papers may provide structural
advantages including increased durability, support, tensile
strength, puncture resistance, handling damage resistance,
environmental damage resistance, shipping damage resistance, etc.
and/or may provide aesthetic advantages including a smoother,
visually appealing, and more abuse resistant the outer surface.
Heavy weight kraft papers, however, may increase that stiffness and
rigidity of the laminate, which may increase a laminate's closure
flap seal failure due to the laminate's resistance to bending or
curling towards the closed position and remaining in the closed
position (i.e., stiff and rigid laminates may be biased toward a
flat or unsealed position).
[0048] The use of a lighter weight kraft paper (e.g., 25-35
pounds/3000 square feet) may increase a laminate's closure flap
seal integrity by decreasing the laminate's resistance to bending
or curling toward the closed position. In addition, the lighter
weight kraft paper may not significantly degrade the beneficial
properties of the laminate so that the laminate's functionality is
not comprised. A paper weight that is roughly 30 pounds/3000 square
feet may provide an optimal level of seal integrity vs. laminate
properties. A further description of the advantages of using a
kraft paper between the range of 25 and 35 pounds/3000 square feet
is provided in U.S. patent application Ser. No. ______ (attorney
Docket No. 018336-016700US) filed on ______ by Bristol et al.,
entitled "Pipe Insulation Products and Methods," the entire
disclosure of which is incorporated herein.
[0049] The present invention, however, is not limited to the use of
a lighter weight kraft paper (or to the use of a kraft paper in
general). The present invention provides increased closure flap
seal integrity regardless of if a heavy weight kraft paper, a light
weight kraft paper, or some other porous media layer is used.
[0050] The laminate 200 additionally includes a polymeric film
sheet outer layer 202. The polymeric film sheet 202 may be made of
polypropylene, polyethylene, polyvinyl chloride, vinyl, saran,
polyethylene terephthalate, thermoplastic polyolefin, etc. The
polymeric film material may be selected as the laminate's outer
layer 200 to provide one or more of the following advantages:
shielding the porous media sheet 204 and/or insulating material
from water vapor absorption; protecting against UV damage;
protecting against mold, mildew, or fungal growth; providing a
smooth, unwrinkled, visually appealing outer surface; etc.
Polymeric film materials generally provide a smoother, more
visually appealing outer surface when compared with traditional
laminates.
[0051] However, the use of a polymeric film sheet outer layer 202
may result in an increased tendency of the closure flap to curl
away from the closed sealed position, or in other words to reverse
curl as described previously. The reverse curl may cause and/or
enhance closure flap seal failure due to providing a lifting force
against the adhesive material. Seal failure may be further enhanced
depending on the climate and conditions the laminate 200 is subject
to and/or may be enhanced because the polymeric film sheet provides
a smoother lower energy surface for the adhesive material to bond
with.
[0052] The reverse curl of the closure flap may be caused and/or
enhanced by the inclusion of the polymeric film sheet 202. For
example, in some embodiments the tension in the polymeric film
sheet 202 (i.e., internal stress) may be greater than the tension
in one or more layers within the laminate 200 (e.g., the porous
media layer 204, the scrim 206, and/or the foil or metallized
polymeric film sheet 208). The greater tension or internal stress
in the polymeric film sheet 202 may cause the laminate to curl so
that the edges of the laminate bend toward the polymeric film sheet
202. The increased tension in the polymeric film sheet 202 may be
due to the process of manufacturing the laminate (e.g., the
polymeric sheet may be tensioned more than the other layers during
manufacturing), to shrinkage of the polymeric film sheet 202 after
manufacturing (e.g., heat shrinkage), to cold working the polymeric
film sheet 202 and/or laminate 200, to shape memory within the
laminate, or may be due to some other process. In some embodiments,
the tension may not be greater in the polymeric film sheet 202 and
the reverse curl may be due to other factors (e.g., creasing of the
laminate, the shipping configuration of the laminate and cold
working or shape memory (see description of FIG. 5), etc.).
[0053] The foil or metallized polymeric film sheet 208, the scrim
206, the porous media sheet 204, and the polymeric film sheet 202
may be bonded or adhered together using one or more adhesives (not
shown). The adhesive or adhesives used may be contact type,
pressure sensitive, heat seal, etc. and may include one or more
additives to enhance the performance, dimensional stability,
moisture resistance, handleability, fire and smoke propagation
resistance, and/or durability of the laminate 200. Examples of
adhesives that can be used include, but are not limited to,
melamine, urea formaldehyde, phenolic, polyurethane, acrylic,
latex, and acrylo-nitrile. Additional adhesives that can be used
include adhesives that can migrate into the porous media sheet 204
to improve the physical characteristics of the laminate 200 (e.g.,
improve UV stability, flame spread resistance, mold growth
resistance, etc.). Examples of such migrating adhesives are
colloidal silica or alumina, sodium or potassium silicate, ammonium
phosphate stabilized with zinc oxide, magnesia or alumina; borax,
and oxi-chloride stabilized with zinc oxide or magnesia.
[0054] FIG. 3 depicts a process 300 of manufacturing a laminate
according to one embodiment of the present invention. The process
300 may be used to induce an inward curling closure flap (i.e.,
produce a positive curl) or, alternatively, reduce the amount of
reverse curl that a closure flap experiences due to manufacturing.
The process 300 may include a plurality of rollers 306 that may
compress a plurality of layers 302 and 304 (e.g., the foil or
metallized polymeric sheet, scrim, porous media sheet, and
polymeric film sheet) to form a single multilayered laminate. The
figures illustrates two layers being compressed together, but the
system could include other layers. In some embodiments, layer 302
includes the polymeric film sheet outer layer and layer 304
includes the foil or metallized polymeric sheet, the scrim, and the
porous media sheet.
[0055] During lamination, tension may be applied to each of the
layers 302 and 304 (shown by element 312 (tension A) and 310
(tension B), respectively). The layers may be kept in tension
during lamination to prevent wrinkles and/or to facilitate winding
of the finished laminate. The tension applied to each of the
laminates, however, may not be uniform. For example, in some
embodiments, tension A, 310, that is applied to the polymeric film
sheet layer 304 may be greater than tension B, 312, that is applied
to the other layers 302 of the laminate. The increased tension
applied the polymeric film sheet layer 304 may result in greater
internal stress within the polymeric film sheet outer layer 304 of
the laminate, which may cause the laminate to curl toward the
polymeric film sheet and thereby cause the reverse curl of the
closure flap. In other embodiments, tension A, 310, may be roughly
equivalent to tension B, 312, but shrinkage (e.g., heat shrinkage)
after lamination may cause the internal stress within the polymeric
film sheet outer layer 304 to be greater than one or more of the
other layers 302. The greater internal stress may result in the
reverse curl of the closure flap.
[0056] According to one embodiment of the invention, the tensions,
310 and 312, applied to the layers, 304 and 302, may be controlled
to increase the post lamination tension or internal stress in the
other layers 302 of the laminate and/or to account for any post
lamination shrinkage that may occur in the polymeric film sheet
layer 304 (i.e., tension A, 310, may be decreased, tension B, 312,
may be increased, etc.). As the tension or internal stress in the
other layers 302 of the laminate are increased relative to the
polymeric film sheet layer 304, the reverse curl may be reduced
and/or a positive curl may be induced so that the closure flap
curls toward the closed sealed position (i.e., the tension or
internal stress within the other layers 302 will cause the laminate
to curl toward the inner layer of the laminate).
[0057] FIG. 4 depicts another process 400 for reducing a closure
flap's reverse curl and/or inducing a positive inward curl. The
process 400 may include a laminate 402 surrounding and bonded to a
tubular core of insulating material 404 as previously described.
The laminate 402 may include a polymeric film material outer layer
having a closure flap 408 with a reverse curl. The reverse curl may
be reduced and/or a positive curl induced by positioning the
closure flap 408 in the closed position, securing the closure flap
408 in the closed position, heat treating the laminate to soften
the polymeric sheet material (i.e., relaxing the polymers to reduce
or eliminate the internal stress or tension), and cooling the
polymeric film sheet so that the polymeric sheet material hardens
or sets and recrystallizes or reforms with a reduced reverse curl
or with a positive curl (i.e., the polymeric sheet material hardens
with the closure flap curling toward the closed position).
[0058] FIG. 4 illustrates the closure flap 408 being secured in the
closed position through the use of a plurality of straps 422, but
any securing device, mechanism, or method may be used to secure the
closure flap 408 in the closed position. For example, the securing
device may include one or more adhesives, weights, clamps, molds,
clips, bands, jackets, etc. Further, the laminate may be heated
and/or cooled using a variety of process such as ovens (radiation,
microwave, etc.), blowers, heating elements, fans, etc. The
laminate 402 may be kept in the secured position until prior to
installation to further configure the closure flap with the
positive curl (i.e., induce shape memory).
[0059] FIG. 5 depicts another process 500 for reducing a closure
flap's reverse curl and/or inducing a positive inward curl. The
figure illustrates a plurality of laminates 502 stacked atop one
another. Each laminate 502 of the plurality of laminates may
include a securing device or mechanism, such as a strap 522, to
secure the laminate's closure flap 508 in a closed position. In
some embodiments, the laminates 502 do not include a securing
device, but are arranged so that the closure flap is positioned in
the closed position as the laminates are stacked atop one another.
The arrangement of the laminates may secure the closure flap in the
closed position (i.e., the adjacent laminates may secure the
closure flap). The plurality of laminates may then be heat treated
to reduce a reverse curl or induce a positive curl as previously
described and/or the laminates may be maintained or held in the
arranged position for a duration of time so that a reverse curl is
reduced or a positive curl is induced (i.e., a positive curl shape
memory is induced, the polymeric film material experiences cold
working, etc.). In some embodiments, the plurality of laminates are
arranged with the closure flap in the closed position, and/or
secured in the closed position, and shipped so that the reverse
curl is reduced or the positive curl is induced during
shipping.
[0060] FIG. 6 illustrates two different laminate configurations
600. The figure shows the surface of the foil or metallized
polymeric film sheet inner layer of both laminates, 602 and 610.
Laminate 602 illustrates a common laminate configuration with the
foil or metallized polymeric film sheet directly adjacent to the
scrim layer (shown by the fiber mesh). The scrim mesh may include a
plurality of fibers having a defined spacing A, 604, and a defined
fiber orientation .theta., 606. The foil or metallized polymeric
sheet layer is generally a thin pliable layer of material. As such,
the scrim fiber mesh often produces contours 608 in the foil or
metallized polymeric sheet layer as the foil or metallized
polymeric film sheet conforms to the individual fiber strands
directly underneath the foil or metallized polymeric film sheet.
The contours may produce areas where the foil or metallized
polymeric material is more prone to damage such as scrapping,
scuffing, tearing, ripping, etc.
[0061] In addition, the contours may produce stress concentration
points within the foil or metallized polymeric sheet, which may
increase the likelihood of tearing, ripping, etc. Likewise, the
contours may limit the amount of stress that may be applied to the
foil or metallized polymeric sheet layer due to tearing and/or
ripping concerns. The contours may cause one or more defects (e.g.,
tearing, scuffing, etc.) to occur to the foil or metallized
polymeric sheet during manufacturing and/or use of the laminate.
According to one embodiment of the present invention, the scrim
fiber mesh may be placed away from the foil or metallized polymeric
sheet so that at least one layer of material (e.g., the porous
media layer) is between the scrim and the foil or metallized
polymeric sheet as illustrated by laminate 610. The layer between
the scrim and the foil or metallized polymeric sheet may act as a
buffer between the layers so that the contours in the foil or
metallized polymeric sheet are reduced or eliminated (illustrated
by the smooth foil or metallized polymeric sheet surface in
laminate 610).
[0062] Because the contours may be removed, the foil or metallized
polymeric sheet may be less prone to scrapping, scuffing, tearing,
ripping, etc. and/or the stress concentration points may be
removed. This may allow the foil or metallized polymeric sheet to
be placed under greater tension without ripping or tearing the foil
or metallized polymeric sheet. The layer directly adjacent the foil
or metallized polymeric sheet (e.g., the porous media layer) may
further add structural support to the foil or metallized polymeric
sheet. The increased tensioning of the foil or metallized polymeric
sheet and/or the added structural support may allow the reverse
curl to be reduce or a positive curl to be induced through
controlled tensioning described in relation to FIG. 3. The removal
or the contours and/or the added structural support may also
minimize the defects that occurs during manufacturing and or use.
The removal of defects in the foil or metallized polymeric sheet
may increase the perm rating of the laminate (i.e., may provide a
more impermeable layer to water vapor and/or other
contaminants).
[0063] In addition, the scrim may be placed directly adjacent to
the polymeric film sheet outer layer, which may add structural
support and/or stability to the polymeric film sheet outer layer.
The added structural support and/or stability may limit the heat
shrinkage of the polymeric film sheet outer layer and/or allow for
greater control over the tensioning of the polymeric film sheet
layer. The added structural support and/or stability of the
polymeric film sheet may reduce the amount of reverse curl that the
closure flap experiences.
[0064] FIG. 7 illustrates various scrim fibers 700 that may be used
to reduce a reverse curl or induce a positive curl. Fiber 702 may
be a straight fiber having a defined diameter 706. The fiber 702
may be biased toward the straight position, which may impede
closure and sealing of the laminate's closure flap due to a force
produced by the fiber 702 as the fiber 702 is forced to bend away
from the straight position. As the diameter 706 of the fiber 702 is
increased, the force produced when the fiber is bent from the
straight position may also increase. The fiber mesh of the scrim
may be designed to have a specific configuration and fiber spacing
(see spacing A and orientation .theta. of FIG. 6) based on the
diameter 706 of the fibers 702 used in the scrim. Closure and/or
sealing of the closure flap may be facilitated by reducing the
diameter 706 of the fibers 702 used and adjusting the fiber
configuration and spacing accordingly. The decreased diameter 706
of the fibers 702 may reduce the force produced when the fibers 702
are bent from the straight position (i.e., smaller and more tightly
spaced fibers may reduce a force produced by the scrim to flatten
out the laminate).
[0065] Similarly, the use of lighter weight fibers, more flexible
fibers, and/or fiber pattern geometry (i.e., the spacing and/or
orientation of the fibers--see A and .theta. of FIG. 6) may further
reduce a force produced when the fibers 702 are bent from the
straight position. Additionally, fibers could be used that produce
a positive curling force in the polymeric film sheet. Fiber 704
illustrates a fiber that may produce a positive curling force. The
positive curl may be induced in the fiber 704 when the fiber is
stretched, heated, exposed to a chemical, etc. Similarly, the fiber
704 may be included in the scrim and laminate so that after
inclusion in the laminate, the fiber scrim mesh provides a positive
curling force on the laminate.
[0066] As previously described, the polymeric film sheet outer
layer may shrink during and/or after manufacturing of the laminate.
The shrinkage may be due to the exposure of the polymeric film
sheet to heat. The heat may be provided by the adhesive used to
bond the layers of the laminate and/or used to bond the laminate
with the insulating material (e.g., hot melt adhesive) and/or may
be provided by residual heat present in the insulating material
when the laminate is bonded to the insulating material (the
insulating material may have residual heat due to one or more
manufacturing processes). The heat from the adhesive and/or the
residual heat present in the insulating material may conduct
through the inner layers of the laminate to the polymeric film
sheet outer layer. Upon exposure to the heat, the polymeric film
material may shrink, which may cause internal stress or tension
that results in reverse curling of the closure flap.
[0067] To reduce the amount of reverse curl in the closure flap,
the polymeric film sheet's exposure to heat may be minimized by
strictly controlling the temperature of the adhesive so that the
adhesive is not applied in excess of the temperature needed and/or
by exposing the insulating material to one or more cooling
processes (i.e., the insulating material may be brought to near
ambient temperature). Minimizing the polymeric film sheet's
exposure to heat may minimize the polymeric film material's heat
shrinkage, which may reduce the closure flap's reverse curl.
[0068] FIG. 8 illustrates a flow diagram 800 of a method for
manufacturing a pipe insulation product according to one embodiment
of the present invention. At block 805, a foil or metallized
polymeric sheet may be provided. The foil or metallized polymeric
sheet may form an inner layer of the laminate and may provide a
fluid vapor barrier to minimize fluid vapor transmission through
the laminate. At block 810, a polymeric sheet material may be
provided. The polymeric sheet material may form an outer exposed
layer of the laminate and may include a closure flap that is
configured to adhesively seal opposite sides of the laminate jacket
so that the laminate forms a hollow cylindrical tube. The closure
flap may curl toward the closed position (or may be configure to
curl more toward the closed position) to provide a greater closure
flap adhesive seal bond.
[0069] At block 815, a scrim may be provided. The scrim may include
a mesh of a plurality of fibers and may be positioned between the
foil or metallized polymeric sheet and the polymeric sheet outer
layer. At block 820, a porous media sheet material may be provided.
At block 825, the foil or metallized polymeric sheet material, the
scrim, the porous media sheet material, and the polymeric sheet
material may be bonded together via an adhesive material to form
the laminate jacket. At block 830, the closure flap may be
configured so that the closure flap includes a curl that provides a
greater closure flap adhesive seal bond.
[0070] At block 835 a tubular core of insulating material may be
positioned relative to the laminate so that the tubular core can be
wrapped or encased within the laminated. At block 840, the laminate
and tubular core may be bonded together to form the pipe insulation
product. The pipe insulation product may be flexible so that the
tubular core and laminate can be opened, placed about a pipe, and
closed without degrading the laminate jacket. At block 845, the
pipe insulation product may be fitted about a pipe to insulate
and/or protect the pipe as described previously.
[0071] In describing the invention, certain embodiments have been
used to illustrate the invention and the practices thereof.
However, the invention is not limited to these specific embodiments
as other embodiments and modifications within the spirit of the
invention will readily occur to those skilled in the art on reading
this specification. Thus, the invention is not intended to be
limited to the specific embodiments disclosed, but is to be limited
only by the claims appended hereto.
[0072] As used herein and in the appended claims, the singular
forms "a", "an", and "the" include plural referents unless the
context clearly dictates otherwise. Thus, for example, reference to
"a process" includes a plurality of such processes and reference to
"the device" includes reference to one or more devices and
equivalents thereof known to those skilled in the art, and so
forth.
[0073] Also, the words "comprise," "comprising," "include,"
"including," and "includes" when used in this specification and in
the following claims are intended to specify the presence of stated
features, integers, components, or steps, but they do not preclude
the presence or addition of one or more other features, integers,
components, steps, acts, or groups.
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