U.S. patent application number 13/890439 was filed with the patent office on 2014-02-06 for bio-pharmaceutical hose.
This patent application is currently assigned to Swagelok Company. The applicant listed for this patent is Swagelok Company. Invention is credited to Robert Bentley.
Application Number | 20140034177 13/890439 |
Document ID | / |
Family ID | 39049422 |
Filed Date | 2014-02-06 |
United States Patent
Application |
20140034177 |
Kind Code |
A1 |
Bentley; Robert |
February 6, 2014 |
BIO-PHARMACEUTICAL HOSE
Abstract
A hose for use in bio-pharmaceutical applications includes an
innermost tubular layer made from a fluoropolymer material. The
tubular layer has an inner, relatively smooth and pure surface that
defines an opening for transfer of various media. A layer of
silicone is disposed next to an outer surface of the innermost
tubular layer through use of, for example, an extrusion method. The
outer surface of the tubular layer may first be modified by various
treatments or chemicals to facilitate the adhesion of the silicone
layer thereto. The silicone material may be solid or foamed. A
reinforcement layer may be disposed adjacent to an outer surface of
the silicone layer. The reinforcement layer may be formed of a wire
braid having gaps. An outer jacket of silicone may be attached to
the reinforcement layer and to the inner silicone layer through the
gaps in the reinforcement layer.
Inventors: |
Bentley; Robert; (Windsor,
CT) |
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Applicant: |
Name |
City |
State |
Country |
Type |
Swagelok Company; |
|
|
US |
|
|
Assignee: |
Swagelok Company
Solon
OH
|
Family ID: |
39049422 |
Appl. No.: |
13/890439 |
Filed: |
May 9, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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13237063 |
Sep 20, 2011 |
8448670 |
|
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13890439 |
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11503868 |
Aug 14, 2006 |
8048351 |
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13237063 |
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Current U.S.
Class: |
138/137 ;
138/141 |
Current CPC
Class: |
B29C 48/153 20190201;
B29C 59/165 20130101; B29C 44/22 20130101; F16L 11/04 20130101;
B29C 48/09 20190201; Y10T 428/1393 20150115; B29C 59/103 20130101;
B29C 59/142 20130101; B29K 2083/00 20130101; B29C 2791/009
20130101 |
Class at
Publication: |
138/137 ;
138/141 |
International
Class: |
F16L 11/04 20060101
F16L011/04 |
Claims
1-20. (canceled)
21. A composite tube comprising: a tubular member through which
media can pass, said tubular member comprising a wall having inner
surface and an outer surface, said inner surface and said outer
surface comprising a fluoropolymer base material, said outer
surface comprising a modified outer surface of said base material
wherein said modified outer surface has a different surface energy
compared with an unmodified outer surface of said base material, a
layer of silicone adjacent to and bonded to said modified outer
surface.
22. The composite tube of claim 21 wherein said tubular member is a
liner in a hose, said inner surface contacting media conveyed
through said hose.
23. The composite tube of claim 21 wherein said fluoropolymer is
selected from the group comprising PTFE, FEP, PFA, ETFE, PVDF.
PCTFE.
24. The composite tube of claim 21 wherein said layer of silicone
comprises an extrusion of mixed catalyst and liquid base
silicone.
25. The composite tube of claim 21 wherein said modified outer
surface comprises a surface that was exposed to at least one of the
following: plasma discharge, corona discharge, laser, sodium
napthalate, ammonium napthalate, ammonia.
26. The composite tube of claim 21 wherein said modified outer
surface has a surface energy that promotes adhesion with silicone.
Description
BACKGROUND OF THE INVENTION
[0001] The invention relates in general to a hose and in particular
to a hose for use in bio-pharmaceutical applications.
[0002] Pharmaceutical companies typically use hoses to transfer
bio-pharmaceutical materials at various locations within the
process of manufacturing pharmaceutical products. These
bio-pharmaceutical materials may include laboratory and food
products as well as various chemicals. A requirement for such hoses
is for the inside surface of the innermost layer of the hose (i.e.,
the surface in contact with the bio-pharmaceutical materials) to be
smooth throughout and of a high degree of purity, and thus free
from becoming contaminated and/or breaking down (i.e., chemically
inert) or degrading relatively quickly over time. Typically the
innermost surface of such hoses is required to be sterilized and
cleaned relatively frequently, for example, by passing pressurized
superheated steam through the hose and/or by an autoclave process.
However, such cleaning processes tend to degrade the innermost
surface of some prior art hoses over time. Other typical
requirements for bio-pharmaceutical hoses include, for example,
resistance from permanent kinking, a relatively high degree of
flexibility, sufficient hoop strength and tensile strength,
relative ease of handling and attachment to mechanical couplings,
and a relatively high degree of vacuum resistance (i.e., the
resistance to being constricted when negative pressure or suction
is applied to the hose).
[0003] Prior art hoses for use in the bio-pharmaceutical industry
typically comprise a single layer of silicone material or a
multi-layered hose having a silicone material for the innermost
tubular member. While the silicone material tends to provide
moderate levels of flexibility and kink resistance (and, thus,
relative ease in handling), the innermost surface of the silicone
material nevertheless tends to become contaminated and/or degraded
relatively quickly over time, particularly by the repeated steam
cleaning process, This results in the replacement of the silicone
material hose more frequently than desired. Other prior art
bio-pharmaceutical hoses have comprised a layer of a relatively
heavy or thick wall of fluoropolymer material where the layer has a
relatively smooth innermost surface and a convoluted or
spiral-grooved outer surface. However, oftentimes the required
smooth finish of the innermost surface of such a hose becomes
undesirably compromised over time (e.g., rippled or otherwise
deformed), particularly when the hose is flexed. Also, other
smoothbore fluoropolymer hoses without a convoluted external outer
surface typically lack flexibility and are relatively heavy and
thus difficult to handle when the inner diameter of the hose
exceeds one inch.
[0004] Still other prior art hoses achieve the required level of
vacuum resistance through use of a reinforcement layer made of
relatively heavy helix wire. However, such a metallic layer tends
to be relatively stiff, thereby requiring a large amount of force
to flex or bend the hose. Further, when bent, the innermost surface
of such a hose tends to lose its smoothness at the point of
bending. In other known hoses, the superheated steam vapor used
during the steam. cleaning process permeates or enters the matrix
of the inner wall material. This tends to accelerate the breakdown
of the innermost surface of the hose.
[0005] What is needed is a bio-pharmaceutical hose having a
relatively long-lasting purity of the innermost surface through
which the bio-pharmaceutical materials are transferred, while
providing a relatively large amount of flexibility and resistance
to kinking and steam permeation and also providing relatively high
tensile and hoop strength and vacuum resistance, and also being
easy to handle and readily attached to mechanical couplings.
SUMMARY OF THE INVENTION
[0006] According to an aspect of the invention, a hose for use in
bio-pharmaceutical applications includes an innermost tubular layer
that comprises, for example, a fluoropolymer material. The tubular
layer has an inner, relatively smooth and pure surface that defines
an opening for transfer of various media. The innermost tubular
layer may be made electrically-conductive by the addition of, e.g.,
carbon material, within the fluoropolymer material. A layer of
silicone is disposed next to an outer surface of the innermost
tubular layer through use of, for example, an extrusion method. The
outer surface of the tubular layer may first be modified by various
treatments or chemicals to facilitate the adhesion of the silicone
layer thereto. The silicone material comprising the layer may be
solid or foamed, and its outer surface may be smooth or convoluted
or corrugated.
[0007] According to a further aspect of the invention, a
reinforcement layer may be disposed adjacent to an outer surface of
the silicone layer. The reinforcement layer may comprise a yarn
textile or wire braid having gaps or interstices. Next, an outer
jacket layer of silicone may be attached to the reinforcement
layer, again through use of an extrusion method. By utilizing a
liquid silicone and subsequently curing the liquid silicone to a
solid state, the liquid silicone can penetrate the gaps of the
reinforcement layer and, upon curing, can adhere relatively
strongly to the outer surface of the inner silicone layer.
[0008] According to yet another aspect of the invention, a
plurality of hoses as described above may be arranged in a hose
assembly where an outer layer of silicone encloses the plurality of
hoses.
[0009] Another aspect of the invention involves a method for making
a hose which includes the provision of an inner tubular member made
from, e.g., a fluoropolymer material, having a smooth innermost
surface. Next, a silicone layer is formed over. an outer surface of
the inner tubular member preferably by a cross-head extrusion
process that utilizes liquid silicone in two separate forms, a
first form of liquid silicone including a liquid platinum or
peroxide catalyzer; and a second form of silicone comprising a base
silicone material having an adhesion promoter. The two separate
liquid silicone elements are extruded onto the outer surface of the
inner tubular member through pumping and metering of the silicone
elements in a certain ratio, and mixing together of the elements to
form a liquid silicone mixture. The mixture is extruded onto the
inner tubular member through use of a cross-head die, and then the
silicone is cured thereby forming a composite tubular hose where
the silicone is strongly bonded to the inner tubular member. The
silicone may also be foamed or aerated to form voids in the
resulting silicone layer. The silicone layer may alternatively have
its outer surface convoluted or corrugated. Optional subsequent
steps may include attaching a reinforcement layer comprising a wire
braid to the outer surface of the inner silicone layer, where the
wire braid has gaps or interstices formed therein. An outer jacket
of silicone may be formed over the reinforcement layer. The outer
jacket may be formed initially from liquid silicone using similar
process steps to those described above for forming the inner
silicone layer. The liquid silicone of the outer jacket penetrates
the gaps in the reinforcement layer during extrusion of the
silicone onto the reinforcement layer such that the liquid silicone
bonds to the outer surface of the inner silicone layer. The liquid
silicone comprising the outer jacket is subsequently cured to form
the multi-layered hose end product.
[0010] These and other objects, features and advantages of the
present invention will become more apparent in light of the
following detailed description of preferred embodiments thereof, as
illustrated in the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is a perspective view, partially broken away, of a
first embodiment of a bio-pharmaceutical hose of the present
invention;
[0012] FIG. 2 is a perspective view, partially broken away, of an
alternative embodiment of the hose of FIG. 1;
[0013] FIG. 3 is a perspective view, partially broken away, of an
alternative embodiment of the hose of FIG. 1 having additional
layers;
[0014] FIG. 4 is a perspective view, partially broken away, of an
alternative embodiment of a bio-pharmaceutical hose of the present
invention having optional layers; and
[0015] FIG. 5 is an end view of a plurality of the hoses of FIGS. 1
and 3 enclosed by an outer layer.
DETAILED DESCRIPTION OF THE INVENTION
[0016] Referring to FIG. 1, there illustrated is a preferred
embodiment of a hose 10 in accordance with the present invention.
The hose 10 includes an inner tubular member or liner 12 that may
comprise a commercially-available fluoropolymer material such as,
for example, polytetrafluoroethylene ("PTFE"), fluorinated ethylene
propylene ("FEP"), perfluoroalkoxy ("PFA"), ethelyne
tetrafluoroethylene ("ETFE"), polyvinylidene fluoride ("PVDF"), or
polychlorotrifluoroethylene ("PCTFE"). Alternatively, the inner
liner 12 may comprise a plastic such as nylon, or another material
such as a liquid crystal polymer. The inner tubular member 12,
which itself may be commercially-available, may be formed by
extrusion as a thin-walled "skin" with a preferred, exemplary
thickness in the range of from 0.001 inches to 0.040 inches. The
diameter of the resulting opening 14 in the member 12 (i.e., the
"inner diameter") may range, for example, from 0.125 inches to 3.0
inches. As generally known to one of ordinary skill in the art, the
size of the inner diameter of the opening 14 of the tubular member
12 determines the thickness of each layer in the hose 10, including
that of the tubular member 12.
[0017] If desired, the fluoropolymer material comprising the
tubular member 12 may be made electrically conductive by the
addition of carbon in the form of, for example, finely divided
carbon black particles or other graphite nanotube additives. Making
the tubular member 12 electrically-conductive allows the member 12
to dissipate any undesired electrostatic charge that may tend to
build up in the hose 10, particularly in the inner tubular member
12, by the media passing through the opening 14 in the inner
tubular member 12. For use in bio-pharmaceutical applications, the
fluoropolymer materials utilized for the member 12 are, in general,
FDA-approved materials that also conform to the U.S. Pharmacopia
("USP") Class 6 purity standard. The inner tubular member or liner
12 thus forms a relatively pure, smooth, chemical- and
temperature-resistant conduit and barrier for the medium which is
conveyed therethrough. In particular, the fluoropolymer member 12
prevents the superheated steam used in the aforementioned steam
cleaning process from permeating into the material comprising the
inner tubular member 12 and causing degradation to such
material.
[0018] An outer surface 16 of the inner tubular member 12 may be
modified by exposure to various treatments and/or chemicals,
including plasma discharge, corona discharge, or laser treatment,
and/or sodium napthalate, ammonium napthalate, or ammonia. The
resulting modified outer surface 16 has a relatively reduced amount
of surface energy, which allows for better adhesion (i.e., reduced
slippage) of the outer surface 16 to an inner surface of the next
layer 18 that comprises the hose 10, discussed hereinbelow.
[0019] Disposed next to the outer surface 16 of the inner tubular
member 12 as part of the hose 10 is a tubular layer 18 that
comprises, in a preferred embodiment, a cross-linked silicone
rubber material. To form the layer 18 next to or over the inner
tubular layer 12, the silicone material may be wrapped around the
outer surface 16 of the inner member 12, or may be over-molded to
the outer surface 16 of the tubular member 12 by injection molding
or cross-head extrusion methods. Preferably, the silicone material
comprising the layer 18 is initially in liquid form and is cured to
a solid state during the bonding process to the outer surface 16 of
the tubular member 12. As a result, the silicone layer 18 forms a
permanent bond to the inner tubular member 12.
[0020] More specifically, in a preferred embodiment of a method
aspect of the invention using a cross-head extrusion technique, the
silicone material comprising the layer 18 may initially include a
liquid platinum or peroxide catalyzer and a separate liquid base
silicone without the catalyzer but containing an adhesion promoter
to promote adhesion to the outer surface 16 of the inner tubular
member 12. The base silicone may be pigmented or clear. Both of
these separate silicone elements are commercially available from,
e.g., Specialty Silicones, Inc. of Ballston Spa, NY. The two
separate silicone elements may be extruded onto the outer surface
16 of the inner tubular member 12 using a displacement pump system
that includes two separate servo-controlled gear pumps for
separately and simultaneously pumping and accurately metering the
liquid silicone elements. The speed of the gear pumps is used to
achieve relatively accurate metering of the silicone elements. The
gear pumps typically pump the separate silicone elements from their
containers through tubes or lines into a static mixing vessel or
tube where the silicone elements are mixed together repeatedly to
form a resulting liquid silicone mixture. In the mixing vessel it
is generally not necessary to adjust the balance of the silicone
elements. Preferably, the two separate silicone elements are mixed
in a certain ratio, preferably a one-to-one ratio.
[0021] The silicone mixture then passes to a cross-head die where
the mixture is extruded at room temperature around the outer
surface 16 of the inner tubular member 12 in a particular profile
(e.g., round or circular, as illustrated in FIG. 1). The cross-head
die typically contains a negative (i.e., vacuum) pressure to remove
any residual air. The inner tubular member 12 with the silicone
mixture extruded thereon may then be passed to an infrared heating
system that cross-links or cures the silicone to a hardened state.
The resulting composite tube 20 comprising the inner tubular member
12 and the silicone layer 18 may then be quenched or cooled,
thereby forming the composite tube 20 end product. During the
extrusion process described above, the inner tubular member 12 may
be pressurized throughout to prevent the member 12 from
collapsing.
[0022] The thickness of the silicone layer 18 may be, for example,
in the range of from 0.080 inches to 0.250 inches. However, the
resulting thickness of the layer 18 depends on the desired inner
diameter of the opening 14 in the tubular member 12, and, as such,
the resulting layer thickness should be apparent to one of ordinary
skill in the art in light of the teachings herein. After adhesion
of the silicone layer 18 to the outer surface 16 of the tubular
member 12 as described hereinabove, the composite tube 20 can be
physically manipulated and kinked without causing any lasting
defect.
[0023] As illustrated in FIG. 1, the layer 18 may comprise a foamed
layer where the silicone material comprising the layer 18 may have
air or some other gas (e.g., Argon/Nitrogen) introduced into it
during the cross-head extrusion technique described hereinabove (or
within some other technique for forming the silicone layer 18) to
form a closed cell foamed or aerated construction of the layer 18,
or may have a blowing or nucleating agent added to it as is known
in the art to form voids in the silicone layer 18 when viewing an
outer surface 22 of the silicone layer 18. Such a foamed
construction gives . the silicone layer 18 various known beneficial
mechanical properties, including lighter weight and/or material
savings. In the alternative, the layer 18 may be of solid silicone
construction.
[0024] Advantageously, the bond between the inner tubular member 12
and the silicone layer 18 that form the composite tube 20 is
generally strong enough to provide the inner tubular member 12 with
a relatively large amount of kink resistance and flexibility, along
with excellent recovery from crushing and kinking without any
undesired separation of the member 12 and the layer 18. That is,
the structural integrity of the composite tube 20 is maintained
throughout typical usage of the hose 10 in various
bio-pharmaceutical applications. In addition, the bond between the
member 12 and the layer 18 can withstand the typical sterilization
temperatures utilized in repetitive steam and/or autoclave
procedures. Thus, the layer 18 provides the composite tube 20 with
sufficient body and strength to be subsequently additionally
reinforced, if desired, by braiding, as discussed hereinbelow. When
flexed or bent into relatively tight bend radii, the silicone
material comprising the layer 18 can stretch on the outside of the
bend and compress on the inside. The silicone material may also
provide an anchor for additional outer layers of the hose 10 to be
adhered to, as discussed hereinbelow, with respect to alternative
embodiments of the hose 10.
[0025] Referring to FIG. 2, an alternative embodiment of the hose
10 of FIG. 1 has the outer surface 22 of the inner silicone layer
18 of a corrugated or convoluted structure. For example, the outer
surface 22 may have a single spiral groove formed therein, or
multiple grooves formed in parallel therein. This provides the hose
10 with various beneficial features, including increased
flexibility and resistance to kinking, and also relatively high
tensile and hoop strength and ease of handling.
[0026] Referring to FIG. 3, an alternative embodiment of a hose 30
of the present invention includes the hose 10 (i.e., the composite
tube 20) of FIG. 1 having a reinforcement layer 24 attached or
disposed adjacent to the outer surface 22 of the inner silicone
layer 18. The inner silicone layer 18 is illustrated in FIG. 3 as
being of solid silicone construction, instead of the foamed
construction of FIG. 1 or the convoluted outer surface 22 of FIG.
2. The reinforcement layer 24 may comprise a tubular wire braid
construction and can be applied to the outer surface 22 of the
silicone layer 18, for example, by known wrapping, knitting or
braiding techniques. The reinforcement layer 24 may comprise a
metal wire or a non-metallic (e.g., yam) textile material such as
cotton, polyester or aramid fiber. For example, using stainless
steel wire with an open pitch provides relatively large gaps or
interstices between the wires, as illustrated in FIG. 1. This
allows an outer jacket 26 of the hose 30, discussed hereinbelow,
which may initially comprise uncured liquid silicone during the
extrusion process discussed herein, to penetrate through the gaps
in the wire braid and abut the outer surface 22 of the inner layer
18. When cured, the silicone comprising the outer jacket 26
provides relatively excellent adhesion to the outer surface 22 of
the inner silicone layer 18.
[0027] However, it is not required for the broadest scope of the
present invention that the reinforcement layer 24 is provided with
a wire braid with gaps or interstices between the wires to allow
the outer jacket 26 to come in contact with the outer surface 22 of
the inner silicone layer 18. The angle of the braid (preferably, 54
degrees) and the tension at which the wire is applied in the
reinforcement layer 24 provides the hose 30 with relatively good
kink resistance when bent or flexed. It also provides the hose 30
with excellent vacuum resistance (i.e., the resistance to
collapsing of the tubular member 12 as well as the inner silicone
layer 18 when negative pressure or suction is applied to the hose).
Further, the tensile properties of the wire comprising the
reinforcement layer 24 provides the hose 30 with the additional
desired properties of flexural memory, suppleness and small bend
radius capability. Also, the hoop strength and tensile strength of
the hose 30 are increased through use of the reinforcement layer
24, which allows for the relatively simple and easy attachment of
the hose 30 to various types of mechanical coupling devices.
[0028] As an alternative to the hose 30 comprising a separate
reinforcement layer 24, the hose 30 may omit the reinforcement
layer 24. The silicone layer 18 may instead contain relatively
short fibers (e.g., aramid) to achieve the desired properties
discussed above. The fibers may be introduced into the silicone
material comprising the layer 18 during the formation of the
silicone layer 18, as discussed hereinabove in the particular
example of a cross-head extrusion process.
[0029] The outer jacket 26 of the hose 30 preferably comprises
another layer of silicone that may be applied onto the
reinforcement layer 24 as a wrapped layer, or may be injection
molded or cross-head extruded, similar to cross-head extrusion
process discussed hereinabove with respect to the formation of the
inner silicone layer 18. The outer jacket 26 provides external
serviceability for cleaning and protecting the inner layers 12, 18,
24 of the hose 30 from external damage. When extruded onto the
reinforcement layer 24, the silicone (initially in liquid form)
comprising the outer jacket 26 penetrates the interstices of the
wire braid to form intimate contact with the outer surface 22 of
the inner silicone layer 18. When cured, the liquid silicone
material provides additional hoop strength to the composite tube 20
comprising the inner tubular member 12 and the inner silicone layer
18. Similar to the inner silicone layer 18, the silicone material
comprising the outer jacket 26 may be of solid construction or may
be foamed by the addition of gas or a blowing agent, resulting in a
closed cell structure. Further, in general when the hose 30
includes the reinforcement layer 26, the outer surface of the outer
jacket 26 preferably is of smooth construction, rather than being
convoluted. In addition, a thermoplastic elastomer material may be
utilized as the material of the outer jacket 26 instead of
silicone. The thermoplastic elastomer material may have an adhesion
system formulated into it.
[0030] Referring to FIG. 4, in an alternative embodiment of the
present invention, a hose 40 includes the inner tubular member 12
of the hoses 10, 30 of FIGS. 1-3. In the hose 40, the inner layer
18 of silicone material is replaced by two separate layers 42, 44.
A first layer 42 may comprise a relatively thin layer of modified
polypropylene. The modifying or coupling agent may be a silane or a
maleic-anhydride material. This material, which forms a permanent
strong bond to the outer surface 16 of the inner tubular member 12,
may be either injection molded or cross-head extruded over the
outer surface 16 of the inner tubular member 12, using known
techniques. The second layer 44 may be a thermoplastic elastomer
from the olefinic family, or may be a urethane. This material can
either be injection molded or cross-head extruded over an outer
surface of the modified polypropylene layer 42, using known
techniques. In general, thermoplastic elastomer materials are less
expensive than silicone, do not need to be sterilized as often, and
may require less processing steps (i.e., omission of the
cross-linking step). Next the reinforcement layer 24 and the outer
jacket 26 may be formed over the layer 44, similar to their methods
of formation over the inner silicone layer 18 as described
hereinabove with respect to the embodiment of the hose 30
illustrated in FIG. 3.
[0031] Referring to FIG. 5, there illustrated is an assembly 50 of
a plurality hoses, specifically, hose 10 of FIG. 1 and the hose 30
of FIG. 3. However, the hose assembly 50 of FIG. 5 may comprise any
combination of the aforementioned hoses 10, 30, 40. As illustrated
in FIG. 3, the two hoses 10, 30 are disposed adjacent one another
in a non-abutting physical relationship, and a single outer sleeve
52 is formed around the hoses 10, 30. The outer sleeve 52 may
comprise a silicone rubber material, similar to that of the inner
layer 18 and/or the outer jacket 26. The outer sleeve 52 may be
formed using a similar cross-head extrusion technique described
hereinabove with respect to the formation of the inner silicone
layer 18, or by some other methods known to one or ordinary skill
in the art.
[0032] With respect to the overall thickness of the hose 10, 30, 40
of the embodiments disclosed and illustrated herein, for an inner
diameter of 1.0 inches, the resulting exemplary thickness of the
entirety of the hose 10, 30, 40 is approximately 0.250 inches.
However, it should be apparent to one of ordinary skill in the art
that the thickness of the hose 10, 30, 40 can vary depending not
only on the desired inner diameter of the opening 14 but on the
number and thickness of the various layers utilized in the
construction of the hose 10, 30, 40.
[0033] The hose 10, 30, 40 of the present invention has been
described for use in bio-pharmaceutical applications. However, the
hose is not limited as such. Instead, the hose 10, 30, 40 of the
present invention may find use in various non-bio-pharmaceutical
applications where is may be desired to utilize a hose having the
physical characteristics and resulting benefits of that described
herein.
[0034] Although the present invention has been illustrated and
described with respect to several preferred embodiments thereof,
various changes, omissions and additions to the form and detail
thereof, may be made therein, without departing from the spirit and
scope of the invention.
* * * * *