U.S. patent application number 12/665868 was filed with the patent office on 2010-12-23 for apparatus and method of zero clearance connection with optional sensing function.
This patent application is currently assigned to SWAGELOK COMPANY. Invention is credited to Richard A. Ales, Mark D. Bearer, Cal R. Brown, Mark A. Clason, Sunniva R. Collins, William H. Glime, Joseph M. Gorley, Stephen W. Moore, Jeffrey S. Rayle, Peter C. Williams.
Application Number | 20100320755 12/665868 |
Document ID | / |
Family ID | 39743764 |
Filed Date | 2010-12-23 |
United States Patent
Application |
20100320755 |
Kind Code |
A1 |
Williams; Peter C. ; et
al. |
December 23, 2010 |
APPARATUS AND METHOD OF ZERO CLEARANCE CONNECTION WITH OPTIONAL
SENSING FUNCTION
Abstract
Apparatus and method for mechanically attached connections of
conduits may include a conduit gripping member (34), a drive member
(36), and a seal member (48), the drive member (36) causing axial
movement of the conduit gripping member (34) to indent into an
outer surface of the conduit when the assembly is pulled-up, the
drive member (36) causing the seal member (48) to form a zero
clearance seal at a location that is axially spaced from the
conduit gripping member (34). The zero clearance seal may comprise
a face seal arrangement including a gasket (48), and the conduit
gripping member (34) may be a ferrule, ring or other device that
can grip and optionally seal against the conduit outer surface. The
assembly may include an optional sensing function for detecting or
sensing a characteristic or condition of an assembly component or
the fluid or both.
Inventors: |
Williams; Peter C.;
(Cleveland Heights, OH) ; Clason; Mark A.;
(Orwell, OH) ; Bearer; Mark D.; (Akron, OH)
; Ales; Richard A.; (Solon, OH) ; Glime; William
H.; (Chagrin Falls, OH) ; Moore; Stephen W.;
(Cleveland, OH) ; Collins; Sunniva R.; (Cleveland
Heights, OH) ; Rayle; Jeffrey S.; (Fairview Park,
OH) ; Gorley; Joseph M.; (Cleveland Heights, OH)
; Brown; Cal R.; (Lyndhurst, OH) |
Correspondence
Address: |
CALFEE HALTER & GRISWOLD, LLP
800 SUPERIOR AVENUE, SUITE 1400
CLEVELAND
OH
44114
US
|
Assignee: |
SWAGELOK COMPANY
|
Family ID: |
39743764 |
Appl. No.: |
12/665868 |
Filed: |
June 25, 2008 |
PCT Filed: |
June 25, 2008 |
PCT NO: |
PCT/US08/68145 |
371 Date: |
December 21, 2009 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60937277 |
Jun 26, 2007 |
|
|
|
61040187 |
Mar 28, 2008 |
|
|
|
61040178 |
Mar 28, 2008 |
|
|
|
Current U.S.
Class: |
285/355 ;
285/335 |
Current CPC
Class: |
G01D 21/00 20130101;
F16L 15/04 20130101; F16L 19/12 20130101; F16L 2201/00 20130101;
F16L 19/0283 20130101; F16L 19/05 20130101; F16L 19/061 20130101;
F16L 19/103 20130101; F16J 15/064 20130101; F16L 19/086 20130101;
F16L 15/08 20130101 |
Class at
Publication: |
285/355 ;
285/335 |
International
Class: |
F16L 15/04 20060101
F16L015/04 |
Claims
1. Fitting for connecting to a conduit end wherein the conduit has
a longitudinal axis, comprising, a first coupling component and a
second coupling component that are joinable together, a conduit
gripping member and a zero clearance seal arrangement, wherein said
conduit gripping member grips an outer surface of the conduit when
the fitting is pulled-up, and said zero clearance seal arrangement
forms a zero clearance seal at a location that is spaced from said
conduit gripping member.
2. The fitting of claim 1 wherein said first and second coupling
components being axially joinable together during pull-up of the
fitting to cause said conduit gripping member to grip the conduit
and to cause said zero clearance seal.
3. The fitting of claim 2 wherein said first coupling component
comprises a female threaded nut and said second coupling component
comprises a male threaded body.
4. The fitting of claim 1 wherein said conduit gripping member
indents into the conduit surface when the fitting is pulled-up.
5. The fitting of claim 4 comprising a gasket disposed between a
first seal surface of a face seal member and a first seal surface
of one of said coupling components, said seal surfaces facing each
other and forming said zero clearance seal with respective opposite
sides of said gasket.
6. The fitting of claim 1 wherein said gripping member comprises an
annular ring.
7. The fitting of claim 1 wherein said gripping member comprises a
ferrule.
8. The fitting of claim 5 wherein said conduit gripping member and
face seal member are adapted to be a joined subassembly prior to
installing said fitting onto a conduit.
9. The fitting of claim 8 wherein said face seal member comprises a
cylindrical extension that holds said face seal member and conduit
gripping member together as a subassembly.
10. The fitting of claim 1 wherein said conduit gripping member
comprises at least portions thereof that are surface hardened.
11. The fitting of claim 10 wherein said surface hardened parts
comprise carburized stainless steel surfaces substantially free of
carbides.
12. A fitting for conduits, comprising: a conduit end portion, a
first coupling component and a second coupling component that are
joinable together, a conduit gripping member, and a face seal
member disposed between said first and second coupling members,
said conduit gripping member indenting into a surface of the
conduit to grip the conduit and said face seal member forming a
zero clearance seal, when the fitting is made up.
13. The fitting of claim 12 comprising a gasket disposed between
said face seal member and said second coupling component, said
gasket forming a zero clearance face seal with each of said face
seal member and said second coupling component when the fitting is
made up.
14. The fitting of claim 12 wherein said face seal member comprises
a seal surface that seals against a seal surface of one of said
first and second coupling members when the fitting is made up.
15. The fitting of claim 1 wherein said zero clearance seal
arrangement comprises a face seal member and seal disposed between
a first seal surface of said face seal member and a second seal
surface, said first and second seal surfaces facing each other and
forming said zero clearance seal with respective opposite sides of
said seal.
16. The fitting of claim 15 wherein said seal comprises a
gasket.
17. The fitting of claim 16 wherein said gasket comprises a flat
metal washer-like device.
18. The fitting of claim 1 wherein said conduit gripping member
comprises a Belleville spring with a radial extension at an outer
circumference thereof.
19. The fitting of claim 1 wherein the conduit and said conduit
gripping member comprise a stainless steel alloy.
20. The fitting of claim 1 wherein said conduit gripping member
comprises a Belleville spring configuration.
21. The fitting of claim 1 wherein said conduit gripping member
comprises first and second frusto-conical walls extending radially
outward and in a first axial direction from a radially inner
portion to a radially outer portion, the radially inner portion
having an annular conduit indenting edge configured to plastically
deform the conduit along a circumferential ring of engagement when
the fitting is pulled up to provide a seal between the conduit
gripping member and the conduit.
22. The fitting of claim 21 wherein during pull-up said conduit
gripping member is axially compressed so as to partially flatten,
reducing a diameter of said radially inner portion to grip the
conduit.
23. A fitting for a fluid conduit mechanically attached connection,
comprising a conduit gripping member, a zero clearance seal element
and a sensor associated with said seal element to detect a
condition or characteristic of a fitting component or fluid
contained by the fitting.
24. The fitting of claim 23 wherein said sensor is one of the
following: a wetted sensor, a non-wetted sensor.
25. The fitting of claims 21 wherein the sensor is integrated with
the seal element.
26. The fitting of claim 25 wherein said seal element comprises an
annular face seal gasket.
Description
[0001] The present application claims the benefit of the following
U.S. Provisional patent applications: U.S. provisional application
Ser. No. 60/937,277, filed on Jun. 26, 2007, entitled Smart
Fittings, U.S. provisional application Ser. No. 61/040,187, filed
on Mar. 28, 2008, entitled Apparatus and Method of Zero Clearance
Connection, and U.S. provisional application Ser. No. 61/040,178,
filed on Mar. 28, 2008, entitled Apparatus and Method of Zero
Clearance Connection with Sensing Function, the entire disclosures
all of which are fully incorporated herein by reference.
BACKGROUND OF THE DISCLOSURE
[0002] The present disclosure relates to mechanically attached
connections such as fittings, joints, couplings, unions and so on
that are used in fluid systems or fluid circuits to contain fluid
flow and fluid pressure. Such mechanically attached connections may
be used with but are not limited to conduit fittings for tube, pipe
or any other type of conduit, and that connect a conduit end to
either another conduit end or to another portion, element or
component of a fluid system. For simplicity and clarity, the term
`fitting` as used herein is intended to be all inclusive of other
terms, for example coupling, connection, union, joint and so on,
that could alternatively be used to refer to a mechanically
attached connection. Such mechanically attached connections are
characterized by a fluid tight seal and mechanical strength to hold
the connection together including sufficient grip of the conduit
under vibration, stress and pressure. Fluids may include gas,
liquid, slurries and any variation or combination thereof.
[0003] Fluid systems and circuits typically use mechanically
attached connections to interconnect conduit ends to each other and
to flow devices which may control flow, contain flow, regulate
flow, measure one or more characteristics of the fluid or fluid
flow, or otherwise influence the fluid within the fluid system.
Fluid systems are found everywhere, from the simplest residential
plumbing system, to the most complex fluid systems for the
petrochemical, semiconductor, biopharmaceutical, medical, food,
commercial, residential, manufacturing, analytical instrumentation
and transportation industries to name just a few examples. Complex
systems may include thousands of fittings, either fittings being
installed as a new installation or as part of repair, maintenance
or retrofit operations, or fittings that were previously
installed.
[0004] The term `mechanically attached connection` as used herein
means any connection for or in a fluid system that involves at
least one connection that is held in place by mechanically applied
force, stress, pressure, torque, or the like, such as, for example,
a threaded connection, a clamped connection, a bolted or screwed
connection and so on. This is distinguished from a metallurgical or
chemical connection most commonly practiced as welding, brazing,
soldering, adhesive and so forth. A mechanically attached
connection may include a combination of mechanical and
metallurgical connections, and often does, and such connections are
also within the term `mechanically attached connections` as they
include at least one such connection.
SUMMARY OF THE DISCLOSURE
[0005] In accordance with one of the inventions presented in this
disclosure, a zero clearance fitting or assembly for a conduit
mechanically attached connection is provided. In one embodiment, a
fitting for conduit connection may include a conduit gripping
member that optionally indents into an outer surface of the
conduit, and may optionally seal against that outer surface. In
another embodiment, the fitting further includes a seal element
that forms a zero clearance seal that is axially spaced from the
conduit gripping indentation. In still a further embodiment, a seal
element is disposed between a facing surface of a face seal member
and a face seal surface on another facing surface. In a more
specific exemplary embodiment, the seal element comprises a gasket
axially compressed between two facing surfaces. In another
embodiment, the conduit gripping member and seal arrangement, and
in some cases additional parts, may optionally be held together as
a separate subassembly or preassembly.
[0006] In accordance with another invention presented in this
disclosure, a mechanically attached connection for conduits is
contemplated that includes a zero clearance seal as part of a zero
clearance fitting or assembly for conduit connection, along with a
sensing function that is integrated or incorporated into one or
more parts of the fitting. In an exemplary embodiment, a sensing
function may be included or associated with a seal element that is
also used to provide a zero clearance seal in the assembly. In a
more specific exemplary embodiment, the sensing function may be
realized in the form of a sensor or device that is embedded,
attached, integrated or otherwise incorporated with or associated
with the seal element.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is an embodiment of a fitting incorporating one or
more inventions disclosed herein, illustrated in longitudinal
cross-section, with the parts assembled in a finger-tight
condition;
[0008] FIG. 2 is an enlarged view of the circle A region in FIG.
1;
[0009] FIG. 3 is an enlarged view of the circled region of FIG.
2;
[0010] FIG. 4 is an enlarged view of the circle B region in FIG.
1;
[0011] FIG. 5 is an enlarged illustration of the fitting of FIG. 1
in a completed pulled-up condition, illustrated in
half-longitudinal cross-section;
[0012] FIG. 6 is another embodiment of the assembly illustrated in
FIGS. 1 and 2, including a sensing function in accordance with
another invention disclosed herein;
[0013] FIG. 7 illustrates an example of a flareless ferrule type
fitting in a finger tight condition including a sensing
function;
[0014] FIG. 8 is another embodiment of a zero clearance fitting,
illustrated in longitudinal cross-section, with the parts assembled
in a finger-tight condition;
[0015] FIG. 9 is an enlarged illustration of the fitting of FIG. 8
in a completed pulled-up condition, illustrated in
half-longitudinal cross-section;
[0016] FIG. 10 is an enlarged illustration of the circled region A
of FIG. 8;
[0017] FIGS. 11-15 illustrate additional alternative embodiments of
zero clearance fittings.
DESCRIPTION OF THE EXEMPLARY EMBODIMENTS
[0018] Although the various embodiments are described herein with
specific reference to a tube fitting, and more specifically to a
tube fitting for stainless steel tubing, those skilled in the art
will readily appreciate that the inventions herein may be used with
any metal or non-metal conduit and any metal or non-metal fitting
components, including but not limited to plastics, polymers and so
on. The inventions may also be used with thinner walled conduits or
thicker walled conduits. As used herein, the term `zero clearance`
refers to an arrangement by which a fitting that has been
previously attached to a conduit end and connected to another fluid
member, such fitting may be loosened to allow separation of the
conduit end from the other fluid member, without requiring axial
displacement of the conduit end. In a more general concept, a zero
clearance fitting facilitates disassembly of the fitting so that
the fitting may be separated without requiring axial displacement
of the conduit end that is attached to the fitting. For example, a
zero clearance fitting that includes a zero clearance seal may
allow separating of a first coupling component--for example a
nut--from a second coupling component--for example a body--to
permit the conduit end to be disconnected from the other fluid
member, with a simple radial movement or displacement. Moreover,
while the exemplary embodiments illustrate a connection between a
conduit end and a particular type of fluid member (a coupling
body), such illustration if for explanation purposes only and
should not be construed in a limiting sense. The inventions herein
may be used to connect a conduit end to any fluid member, such as
but not limited to, another conduit end, a coupling component or
member, a flow control member such as a valve, regulator, filter
and so on. The zero clearance aspect of the present inventions
facilitates installing and removing a fitting in a fluid system or
circuit by eliminating any need for axial displacement of the
conduit end relative to the other fluid member it was coupled to,
all while maintaining conduit grip and seal when the fitting is in
an installed and completed pulled-up condition. By finger-tight
condition is meant that the various parts have been assembled onto
a conduit end but in a fairly loose or sometimes snug condition
achieved by the rather low manual assembly force or torque. By
`completed pulled-up condition` is meant that the fitting has been
tightened onto a conduit end to complete a connection between the
conduit end and another fluid member, with an established conduit
grip and seal. Between finger-tight and completed pulled-up
condition may be intermediate pull-up and assembly steps as the
fitting is being tightened. Also used herein is the term "make-up"
or a fitting that is "made-up" which is similar to "pull-up" in
that the terms refer to the process of assembling and tightening
the fitting onto a conduit end. Reference herein to a `subassembly`
or `preassembly` of fitting parts, and derivatives of those terms,
refers to two or more parts that may separately be assembled or
joined and held together by any convenient arrangement or method as
an integral or single unit to simplify final assembly of the
fitting by reducing the opportunity for incorrect installation of
the various parts. The terms fluid system and fluid circuit are
used somewhat interchangeably herein, with a fluid system generally
referring to a more complex arrangement for fluid containment,
whereas a fluid circuit may be as simple as a conduit connected to
another fluid device by a mechanically attached connection. The
present inventions are applicable to all different kinds of fluid
systems and circuits regardless of the complexity.
[0019] The present disclosure also relates to including a sensing
function with a mechanically attached connection including but not
limited to a zero clearance fitting, assembly or mechanically
attached connection for conduits. As used herein, sensing function,
and any embodiment of a sensing function in a `sensor`, is intended
to be construed in its broadest context as the capability, for
example, but not limited to, sense, detect, measure, indicate,
report, feedback or collect, or any combination thereof,
information, condition, status, state or data relating to the
fitting or assembly, one or more of the fitting or assembly
components, members or parts, and/or the fluid contained by the
fitting or assembly. By sensing fluid contained by the fitting is
meant sensing the fluid within the boundaries of the fitting, as
distinguished from a sensor or sensing function downstream or
upstream of the fitting assembly. The sensing function may be
realized by a sensor that is either wetted or non-wetted or both. A
wetted sensor is one having at least a portion thereof exposed to
the fluid contained by the fitting or mechanically attached
connection, while a non-wetted sensor is one that is isolated from
contact with the fluid.
[0020] While various inventive aspects, concepts and features of
the inventions may be described and illustrated herein as embodied
in combination in the exemplary embodiments, these various aspects,
concepts and features may be used in many alternative embodiments,
either individually or in various combinations and sub-combinations
thereof. Unless expressly excluded herein all such combinations and
sub-combinations are intended to be within the scope of the present
inventions. Still further, while various alternative embodiments as
to the various aspects, concepts and features of the
inventions--such as alternative materials, structures,
configurations, methods, circuits, devices and components,
software, hardware, control logic, alternatives as to form, fit and
function, and so on--may be described herein, such descriptions are
not intended to be a complete or exhaustive list of available
alternative embodiments, whether presently known or later
developed. Those skilled in the art may readily adopt one or more
of the inventive aspects, concepts or features into additional
embodiments and uses within the scope of the present inventions
even if such embodiments are not expressly disclosed herein.
Additionally, even though some features, concepts or aspects of the
inventions may be described herein as being a preferred arrangement
or method, such description is not intended to suggest that such
feature is required or necessary unless expressly so stated. Still
further, exemplary or representative values and ranges may be
included to assist in understanding the present disclosure,
however, such values and ranges are not to be construed in a
limiting sense and are intended to be critical values or ranges
only if so expressly stated. Moreover, while various aspects,
features and concepts may be expressly identified herein as being
inventive or forming part of an invention, such identification is
not intended to be exclusive, but rather there may be inventive
aspects, concepts and features that are fully described herein
without being expressly identified as such or as part of a specific
invention, the inventions instead being set forth in the appended
claims. Descriptions of exemplary methods or processes are not
limited to inclusion of all steps as being required in all cases,
nor is the order that the steps are presented to be construed as
required or necessary unless expressly so stated.
[0021] With reference to FIG. 1, a first embodiment of one or more
of the inventions is presented. An assembly 10 for mechanically
attaching or connecting a conduit end C to another fluid member is
illustrated. The assembly 10 is also referred to herein as a
mechanically attached connection or fitting, but the term fitting
is intended to be broadly construed as any arrangement by which a
conduit end may be mechanically attached or connected to another
fluid component. For reference purposes only, the conduit C has a
central longitudinal axis X. Reference herein to `axial` movement
or displacement and `radial` movement or displacement is made with
respect to the axis X.
[0022] The assembly 10 may include a first coupling member or
component 12 and a second coupling member or component 14. The
coupling components may be any suitable arrangement by which the
assembly 10 is installed with conduit grip and seal on the conduit
end C. For the FIG. 1 embodiment, the first coupling component 12
may be realized in the form of a female threaded nut, and the
second coupling component may be realized in the form of a male
threaded body. Typically, a coupling member in the form of a `body`
receives the conduit end, typically but not necessarily in a
conduit socket. However, in the case of zero clearance fittings as
taught herein, the body 14 provides a zero clearance seal surface
as will be described below and does not receive the conduit C end.
However, the body 14 may have end configurations such as at 16 that
do accept a conduit end. Therefore, for purposes of this disclosure
we consider a body to be a coupling member that is joinable to
another coupling member such as a nut. A coupling member in the
form of a `nut` is joined to the body to tighten or pull-up the
fitting to a made condition with proper conduit grip and seal, with
the nut typically including a drive surface that engages the
conduit gripping member during pull-up or may alternatively engage
a drive member that engages the gripping member. These components
(such as the nut and body for example) are `coupling` in the sense
that they can be joined together by relative axial movement with
respect to each other, and tightened so as to install the assembly
10 onto the conduit end C so that the assembly 10 grips the conduit
to prevent the conduit from loosening under any one or more
environmental stresses such as temperature, pressure, strain and
vibration to name a few examples. The assembly 10 also provides a
seal against loss of fluid. The fluid that is carried by the
conduit C may be gas, liquid, a combination thereof or any other
fluid medium. The assembly 10 may find typical application in
making connections within an overall fluid system. It should also
be noted that one or both of the coupling members may in practice
be part of or integral with a fluid component, and not necessarily
a discrete component as illustrated herein. For example, the body
14 may be integrated or associated with another device or
structure, such as a fluid control device such as a valve or valve
body, flow meter, tank, a manifold or any other fluid component to
which a conduit is to be attached.
[0023] The coupling body 14 may itself be considered a fluid member
that is connected to the conduit end C, or may include an end
configuration 16 that may be further connected to another part,
such as a fluid component, another conduit end and so on. As shown,
the end connection 16 of FIG. 1 may include a male threaded end 18
of a conventional tube fitting body, but any end connection
configuration may be used as needed to connect the conduit end C
into the fluid system or to another fluid member.
[0024] Although this embodiment provides for a threaded connection
between the first and second coupling components 12, 14, threaded
connections are only one of the many available choices.
Alternatives include but are not limited to clamped or bolted
connections. The type of connection used will be determined by the
nature of the force needed to secure the assembly 10 to the conduit
end in a fluid tight manner. Generally speaking, a fitting such as
illustrated in FIG. 1 may be used for a flareless end connection,
meaning that the conduit cylindrical shape is not flared as a
processing step prior to connection to another fluid member
(although the conduit may plastically deform during the
installation process). The conduit end does not require any
particular preparation other than perhaps the usual face and debur
process for the end surface C1 (FIG. 2). In still a further
alternative embodiment, the male and female threading may be
reversed for the first and second coupling components.
[0025] The first coupling component 12 and second coupling
component 14 may include wrench flats 20, 22 respectively to assist
in joining and tightening the assembly 10 together during pull-up
of the fitting. Relative rotation between the coupling components
12, 14 may be used to tighten and loosen the fitting as
appropriate.
[0026] The body 14 may include a central bore 24 having a diameter
that is about the same or the same as the diameter of inside
cylindrical wall 26 of the conduit C. For most connections,
although not necessarily required in all cases, the bore 24 and
conduit C are aligned and assembled in a coaxial manner along the
axis X.
[0027] The second coupling component 14 further includes a first
end face or facing surface 28 at an inner end portion 30 thereof.
This end face or facing surface 28 presents a seal surface 32 for
purposes which will be more fully explained herein below. The seal
surface 32 in this embodiment comprises a generally planar face
seal surface, however, other seal surface configurations may be
alternatively used based on the type of seal that will interface
with the seal surface 32. For example, in the embodiment of FIG. 1,
the seal surfaces may include recesses (not shown) that help to
align the beads of the seal element 48 during assembly and
tightening. From FIG. 1 it will be appreciated that when the first
and second coupling components 12, 14 are separated, for example
after the fitting 10 has been installed on a conduit end, a simple
radial movement or displacement may be used to undo the assembly
10, or in other words to separate the conduit end C from the body
14. This configuration thus achieves a zero clearance connection
because the fitting components can be separated without need for
axial movement of the conduit C relative to the body 14. In various
embodiments, though not necessarily required in all cases, the zero
clearance seal is axially separated or spaced from the conduit
gripping member, particularly the region where the conduit gripping
member indents or otherwise grips the conduit outer surface.
Accordingly, the seal that is made at the facing surface 28 is
referred to herein as a zero clearance seal, and the assembly or
fitting 10 is referred to herein as a zero clearance assembly or
fitting. More generally, a zero clearance seal arrangement
comprises those parts that together form a zero clearance seal when
the fitting is pulled up. In this first embodiment then, a zero
clearance seal arrangement may include a face seal insert (40, see
below), a seal element such as a gasket for example (48, see below)
and one of the coupling components, in this example the body 14.
But many alternative embodiments may use different parts and
different configurations and shapes to effect a zero clearance
seal. In an alternative embodiment, the beads may be provided on
one or both of the planar facing surfaces, rather than on the
gasket, and the gasket may have flat planar surfaces. Additionally,
a zero clearance fitting is provided wherein after disassembly the
gripping member remains on the conduit, thus facilitating re-makes
of the fitting 10 (a re-make refers to subsequent make-up or
pull-up of the fitting after a prior installation of the fitting on
a conduit end).
[0028] With reference to FIGS. 1 and 2, the assembly 10 may further
include one or more parts that may be used to effect conduit grip
and seal. A conduit gripping member 34 may be provided to grip the
conduit C against an outer surface C2 thereof. For higher pressure
applications it may be desirable for the gripping member 34 to
indent, cut or bite into the conduit outer surface C so as to
provide a strong gripping pressure and resistance to the conduit C
backing away under pressure and potentially compromising fluid
tight seals within the fitting 10. However, in lower pressure
applications the gripping member 34 may be designed to adequately
grip the conduit without actually indenting or cutting the conduit
surface C2. In addition to providing an appropriate gripping force
on the conduit C, the gripping member 34 may also provide a primary
or secondary fluid tight seal against the conduit external surface
C2 to protect against loss of fluid from the assembly 10.
Therefore, as understood herein, a conduit gripping member is any
part or combination of parts that, upon complete pull-up of the
fitting, grips the conduit against pressure, vibration and other
environmental effects, and optionally also may provide a fluid
tight seal.
[0029] A drive member 36 may be used to assist in applying the
needed force to the conduit gripping member 34 during pull-up of
the fitting so as to cause the gripping member 34 to deflect or
otherwise deform (from its unstressed condition such as in FIG. 1)
to grip and optionally seal against the conduit C. In alternative
applications, the drive member 36 may not be needed, and an
interior surface such as a drive surface 38 of the first fitting
component 12 may be used (with additional suitable modifications to
the gripping member 34 and seal member 40) to drive the gripping
member 34 into gripping engagement with the conduit C.
[0030] A face seal member or insert 40 may be used to assist or in
cooperation with the driving member 36 in causing the gripping
member 34 to grip and optionally seal against the conduit C. The
face seal member 40 may optionally provide another primary or
secondary seal area where the gripping member 34 engages with an
interior surface 42 of the face seal member 40. The face seal
member 40 is referred to herein as a seal member because a
significant though optional aspect of that component is to provide
an end face 44 that presents a second seal surface 46 that faces
the first end face 28 and first seal surface 32 of the second
coupling component 14. In this exemplary embodiment the seal
surfaces 32, 46 are generally flat planar facing surfaces and
function as face seal surfaces, in that the fluid tight seal areas
are presented in the generally planar surfaces 28, 44. Again, the
face seal surfaces 32, 46 may be configured as needed to conform to
the shape or geometry of an intermediate seal element 48. In many
embodiments, the face seal member 40 may be realized in the form of
a gland or body having an appropriate geometry and configuration to
present a seal surface to one side of the seal element 48.
[0031] With reference to FIGS. 2 and 4, the seal element 48 may be
realized in any form that is suitable to provide a zero clearance
seal between the conduit gripping member 34 and the second coupling
member 14. One example of many is a seal configuration in which a
face seal is provided between seal surfaces 50, 52 of the seal
element 48 and facing seal surfaces 32 and 46, so as to form a zero
clearance seal when the fitting 10 is adequately pulled-up.
[0032] In the exemplary embodiment of FIGS. 2 and 4, the seal
element 48 may be realized in the form of a face seal gasket of
conventional or special design, or as another alternative as shown,
have a generally flat, thin washer-like body 54 with an annular
sealing bead 56, 58 on either side and facing their respective face
seal surfaces 46, 32. Preferably, the relative hardness between
each sealing bead 56, 58 and its respective facing surface is such
as to promote a good seal when the parts are axially compressed
together. Whether the seal surfaces 50, 52 are harder than or
softer than the respective facing surfaces 46, 32 is a matter of
design option.
[0033] The seal element 48 need not have the sealing beads 56, 58
but instead may be flat or may have other features and shapes to
promote a good face seal and zero clearance. As another
alternative, the beads may be formed on the facing surfaces 44, 28.
Other alternatives include but are not limited to using a seal
element that is all metal, non-metal or a combination thereof. For
example, an elastomer or plastic material may be included with the
seal element 48 or with the facing surfaces 28, 44, or both, as
needed and as compatible with the system fluid.
[0034] With continued reference to FIGS. 2 and 4, the seal element
48 may include a radially tapered collar portion 60 that forms a
socket or recess 62. This socket 62 may be used to provide a
locator position for the conduit end C1. The socket 62 is defined
in part by a tapered and inwardly recessed wall 64 against which
the conduit end C1 may abut to indicate to the assembler that the
conduit is fully inserted into the fitting 10. The seal element 48
also may include a through passage 66 that is circumscribed by an
interior cylindrical wall 68. The diameter of the wall 68 as well
as the geometry and material of the seal 48 may be selected so that
upon complete pull-up of the fitting, the wall 68 forms a bore line
or near bore line continuity between the conduit cylindrical wall
26 and the body central bore 24, so as to reduce entrapment areas
at the connection. The tapered wall 64 and cylindrical wall 68
converge at an annular edge 70. This edge 70 may be used to provide
a seal area against the conduit end C1 if needed, either as a
back-up seal for the bead 56 and the gripping member 34, or as a
primary seal.
[0035] In the illustrated exemplary embodiment of FIGS. 1-3 and 5,
and with particular reference to FIG. 3, the conduit gripping
member 34 may be realized in the form of a conically shaped body 72
which in some respects may be comparable to a spring washer.
Accordingly, the body 72 may include a central opening 74 that is
defined in this example by a radially inner cylindrical wall 76,
and that allows the conduit C to be slid there through during
assembly of the fitting 10. A common example of a spring washer
geometry is a Belleville spring, although such geometry is only
exemplary. Belleville springs generally are used to provide a
live-load or bias against a surface in a direction along a central
longitudinal axis of the spring, in terms of FIG. 1 in a direction
that is parallel to the axis X. Our concept in one embodiment is to
use a spring washer approach to effect conduit grip and optionally
a seal by a radial compression against the conduit outer surface C2
brought about when the spring is axially loaded. An axial load
against the conduit gripping member 34 causes the spring to deform
to a flatter condition, as compared for example to the spring in an
unstressed condition, which produces an inward radial compression
of the spring against the conduit C. This concept of using a spring
washer to effectively grip and optionally seal against an outer
surface of a conduit is fully described in International Patent
Application number PCT/US2006/024776 published as WO 2007/002576 A2
on Jan. 4, 2007 and fully incorporated herein by reference. A copy
of such disclosure is appended to the provisional application
referenced herein above.
[0036] In the embodiment of FIG. 3, the conically shaped body 72
comprises two generally and optionally parallel frusto-conical
walls 80, 82 extend from the radially inner wall 76 to an optional
radial extension 84. A typical Belleville spring does not use the
extension 84, and the present inventions may be used with such
conventional spring designs in many cases. The outer frusto-conical
wall 80 and the inner cylindrical wall 76 converge at a front end
or edge 86 of the spring washer 72. This front edge 86 may be but
need not be a sharp edge, and preferably may be of such
configuration and shape as to indent or embed into the outer
surface C2 of the conduit when the fitting 10 is pulled up. During
pull-up, in addition to the radial compression against the conduit
outer surface, there is a slight axial movement of the front edge
86 as the spring begins to flatten. The front edge 86 is also
radially directed against the conduit surface by engagement with
the tapered or frusto-conical surface 42 of the face seal member
40. These movements cause the front edge 86 to indent or penetrate
into the conduit outer surface C2 (see the discussion below
relating to FIG. 5). By indenting into the conduit surface, the
conically shaped body 72 will exhibit a high gripping strength
against any tendency for the conduit C to try to back out of the
fitting, especially under pressure. For lower pressure
applications, however, it may not be necessary to have a biting or
indenting type effect on the conduit. The conically shaped body 72
may have many alternative geometries and configurations to promote
the grip and seal functions as needed and as needed for particular
overall fitting 10 configurations and designs.
[0037] The gripping member 34 initially engages the interior
surface 42 of the face seal member 40 down near the conduit
surface, as illustrated in FIG. 3 in the finger-tight condition of
the fitting. The interior surface 42 is frusto-conical so as to
present a camming surface for the conically shaped body 72, and
also to provide a limit on the deflection of the conically shaped
body 72 during pull-up. The forward or outer frusto-conical wall 80
and the interior surface 42 may define an included suitable angle
.alpha., while the rearward or inner spring wall 82 and an outer
tapered frusto-conical surface 88 of the drive member 36 may define
an included suitable angle .beta.. In many cases, the angles
.alpha. and .beta. may be the same or nearly the same, but in other
cases they may be different, depending on the design and operation
of the gripping member 34. The surfaces 88 and 42 cooperate to
control deflection of the conically shaped body 72 in a manner
desired to achieve the desired grip and optional seal against the
conduit outer surface C2. This control of the deflection may be
further enhanced with the use of the optional radial extension 84
that engages a corresponding radial extension 90 on the drive
member 36. As the drive member 36 is axially moved against the
conically shaped body 72, axial movement of the forward edge 86 is
restricted by the face seal member 40, and so the conically shaped
body 72 begins to flatten, which in cross-section appears as the
walls 80, 82 moving towards a more vertical orientation. This
causes in inward contraction of the cylindrical wall 76, in other
words a decrease in its diameter, thus causing the forward edge 86
to indent or bite into the conduit, and for the cylindrical wall 76
in general to swage against the conduit C2. By swage is meant that
the conduit surface is radially compressed to a smaller diameter,
with either plastic or elastic deformation. In alternative cases,
especially for lower pressure applications, it may be sufficient
for the spring wall 76 to be compressed against the conduit to in
effect collet with a radial load against the conduit outer surface,
even if the compression is not as much as would be considered a
swaging action. Because the conically shaped body 72 does not fully
plastically deform and stores potential energy as it is flattened,
we consider this design to be a live loaded, and further, the
design allows for re-make of the fitting 10, in other words, a
fully tightened fitting may be untightened and then re-made with
the same resulting conduit grip and seal as needed. Note further
that as system pressure increases, the pressure force tends to push
the conduit back out of the fitting 10 (as viewed in FIG. 1, from
right to left for example). For designs in which the conically
shaped body 72 convex side faces the high side system pressure,
this tendency for the conduit to attempt to shift out of the
fitting results in the conically shaped body 72 becoming even more
compressed, causing the conically shaped body 72 to indent further
into the conduit and also grip the conduit surface tighter. We call
this action an energized conduit grip because the gripping strength
increases with increasing system pressure.
[0038] It should be noted that while the gripping member 34
illustrated herein is a spring washer type configuration, such is
not required, and other annular ring-like conduit gripping and
sealing members may alternatively be used.
[0039] The face seal member 40 may include an optional cylindrical
extension 92 that extends rearward of the conduit gripping member
34, and shrouds about the conduit gripping member 34 and a portion
of the drive member 36. The rearward extension 92 may include a
hook 94 or similarly functioning and somewhat flexible member that
can snap over a back end 96 of the drive member radial extension
90. This arrangement may be used to couple the drive member 36, the
conduit gripping member 34 and the face seal member 40 together as
a unified subassembly or preassembly 98 (FIG. 1) that may be use to
simplify assembly or field use of the fitting 10 so as to reduce
chances of improper installation. Techniques other than a clip
together arrangement may be used to hold the parts together as a
subassembly 98. A subassembly may also include additional parts or
fewer parts as needed. For example, the seal element 48 may be
included in a subassembly. Another alternative, in some cases the
drive member 36 may not be needed, but rather the surface 38 of the
nut may be used to drive the conically shaped body 72 against the
face seal member 40. In such an alternative, the conduit gripping
member 34 and face seal member 40 may be joined as a subassembly or
optionally may include the seal element 48 as part of the
subassembly. In any case, a subassembly of selected parts that has
been fully tightened onto the conduit end will remain on the
conduit end after disassembly, loosening, uncoupling or separation
of the nut 12 from the body 14.
[0040] The cylindrical extension 92 may also include an inner end
surface 99 that optionally engages the nut drive surface 38 with a
camming action that causes inward radial deflection of the hook or
end 94 (see FIG. 5 also). This causes the hook or end to be crimped
or compressed against the drive member 36, for example an
optionally tapered outer surface 36a of the drive member. This
assures that when a tightened fitting is subsequently loosened or
disassembled, the face seal member 40 may remain assembled with the
drive member 36 and gripping member 34 as a subassembly 98 on the
conduit end.
[0041] The drive member 36 may further include an optional rearward
cylindrical extension 100 that engages the nut drive surface 38
with a camming action that causes the extension 100 to inwardly
deflect or crimp against the conduit outer surface C2 (see FIG. 5).
This crimping may optionally include indenting into the conduit but
is not required. An optional lubricating material, for example a
resin or lubricant 102, such as for example, ultra-high molecular
weight (UHMW) polyethylene or UHMW-PE, may be initially placed in
the pocket 104 defined by the rearward extension 100. After
complete pull-up, the lubricating material is squeezed or displaced
into the contact region between the crimped extension 100 and the
conduit surface C2. The lubricating material serves to reduce the
effects of abrasion and fretting of the conduit surface that may
occur as a result of vibrations and bending moments in the
conduit.
[0042] With reference to FIG. 5, we illustrate an exemplary
configuration of the fitting 10 in a fully pulled up and tightened
condition. It will be noted that the gripping member 34 is somewhat
flattened sufficiently to achieve the desired conduit gripping
force by swaging in the region 106 the now smaller cylindrical wall
76 onto the conduit. In some cases this may include forming a
shoulder 108 by biting into the conduit surface. This shoulder 108
will press against the front edge 86 of the gripping member 34 in
response to pressure which will help prevent the conduit from
backing out, and as pressure increases will cause the gripping
member to grip even tighter due to further flattening of the
gripping member 34. The rearward cylindrical extension 92 of the
face seal member 40 has been crimped over the drive member 36, and
the rearward cylindrical extension 102 has been crimped onto the
conduit, with the lubricating material 102 displaced into the
crimped region. The seal element 48 has also been axially
compressed between the facing seal surfaces 32, 46 so that the
beads 56, 58 form zero clearance face seals therewith. The beads
56, 58 are illustrated with an exaggerated indenting in to the
surfaces 32, 46 for ease of understanding. In all the drawings
herein, various gaps, spaces and alignments may be somewhat
exaggerated for ease of illustration and clarity.
[0043] The indented gripping member 34 thus provides grip and seal
along the outer conduit surface (for example in the region
generally indicated with the numeral 106), the gripping member 34
also provides a seal against the face seal member surface 42 as in
the region generally indicated with the numeral 107, and the seal
element 48 provides zero clearance seals 109 with the face seal
member 40 and with the body end portion 30. These seals provide a
fully sealed connection between the conduit end C and the fluid
flow path through the body 14.
[0044] In order to further increase the pressure rating of the
fitting 10, various parts or surfaces may be treated to be surface
hardened as compared to the core material. One exemplary suitable
process is low temperature carburization which produces a hardened
surface that is substantially free of carbides in stainless steel
alloys, however, other hardening processes including work hardening
and non-low temperature carburizing, nitriding and others may be
used as needed based on the desired hardness and corrosion
resistance properties needed for a particular application. For
example, for a stainless steel fitting 10, it may be desirable to
surface harden the beads 56, 58 or the seal surfaces 50, 52 (FIG.
4). It may also be desirable in some designs to harden the entire
surface of the conduit gripping member 34, or alternatively the
inward portion 110 (FIG. 3) that will indent into and compress
against the conduit C. This may be especially useful when the
conduit comprises a hard alloy material, such as 2205 or 2507
duplex stainless steel, to name a few of many examples. It may also
be desirable in some applications to harden the outer portion 112
of the gripping member 34 (FIG. 3), because just as the inner
diameter of the spring washer 72 tends to decrease as the spring is
flattened, the outer diameter tends to increase. By hardening the
outer portion 112 this tendency to increase the diameter of the
spring washer 72 will be lessened. The fitting may also be designed
so that the outer rim 114 of the spring washer 72 engages and is
radially constrained by the inner surface 116 of the rearward
cylindrical extension 92 of the face seal member 40.
[0045] During pull-up, the nut 12 axially advances, relative to the
fitting body 14, and somewhat flattens the conduit gripping member
34 to indent into the conduit surface, and also effects the radial
face seal between the face seal element 48 and the face seal member
40 and the body 14. The body 14 may be, for example, a standard SAE
face seal design that would normally accommodate, for example, an
o-ring face seal. The face seal member 40 has an opposite surface
42 adjacent to the spring 34, having an angle .alpha. with the free
and non-flexed conduit gripping spring (in a finger-tight condition
such as FIG. 1), and participates with the flattening of the
conduit gripping member 34 during pull-up. Opposite the conduit
gripping member 34 is the drive member 36 such as a gland, likewise
having an appropriate surface 88 (FIG. 3) adjacent to the conduit
gripping member 34 with an angle .beta., which also participates
with the flattening of the spring during pull-up while the pull-up
also effects the face seal.
[0046] The face seal member 40 has the optional rearward extending
cylinder 92 that shrouds about the conduit gripping member 34 and
much of the drive member 36. The end of the rearward extending
cylinder 92 optionally has a radially inward hook that snaps over a
radial shoulder 90 on the drive member 36. When snapped together,
the drive member 36, gripping member 34, and face seal member 40
form a sturdy cartridge sub-assembly 98 that can be handled,
stored, and inventoried as a single unit. As such, within this
cartridge 98 prior to pull-up, the gripping member 34 is in its
free and un-flexed state. When used, the cartridge 98 may be placed
in the nut 12 which is then assembled to the body 14. The conduit
end is inserted into the end of the nut 12, through the cartridge
sub-assembly 98, and up against the zero clearance face seal
element 48. The nut is advanced to create (a) a sealing grip on the
conduit, by virtue of flattening the gripping member 34, and (b) a
zero clearance face seal on the body 14. In the course of pull-up,
the camming drive surface 38 of the nut crimps the end 94 of the
rearward extending cylinder radially and more firmly onto the drive
member 36, particularly onto an included surface 36a on the drive
gland. The drive member 36 may have the optional smaller rearward
extending cylinder 100 that shrouds about the conduit upon
assembly. Within the smaller rearward extending cylinder may be a
deposit of resin or other suitable lubricant material 102 applied
along the circumference of the inside diameter of the smaller
rearward extending cylinder. Upon pull-up, the camming drive
surface of the nut likewise crimps the end of this smaller rearward
extending cylinder radially and onto the surface of the conduit.
The lube material 102 is displaced onto the conduit surface and
into the contact zone between conduit and the crimped end of the
smaller rearward extending cylinder. This lubed crimping action
creates a resistance to potentially damaging effects of fluid
system vibration. Should the fitting become disassembled, for
maintenance of the fluid system or for other purposes, the
cartridge sub-assembly 98 stays fixed on the end of the conduit.
The nut, captured on the conduit end by the cartridge sub-assembly,
is free to slide back on the conduit. This fitting is said to have
a zero-clearance design because the body can then be lifted
radially away from the conduit end without having to first pull the
conduit end axially out of the body. When the fitting is
re-assembled (after fluid system maintenance, for example) the nut
is slid back over the conduit gripping cartridge sub-assembly 98
and pulled-up on the body. Fluid seals are re-established on the
conduit surface and at the body face seal. This fitting design has
the further advantage of tighten-ability. Should the fitting
develop a leak (due to any of a number of reasons including
insufficient pull-up) the nut can be tightened further onto the
body such that the sealing members engage further and shut-off the
leak.
[0047] As noted, the conduit gripping member 34 may have a
basically conical shape, also called a Belleville or
Belleville-like spring, which has a central hole 76 or inner
diameter through which a conduit can pass. Pressing the spring
axially so as to flatten it causes that central hole to decrease in
diameter such that its edge indents into the surface of the conduit
and grips the conduit in place. Configured in a conduit fitting,
the flattening of a gripping spring is accomplished by pulling-up
or advancing the nut relative to body such that surfaces adjacent
to the gripping spring would impart a toroidal flexure or
flattening of the gripping spring. These adjacent surfaces start
out having an angle .alpha. and .beta. with the free and non-flexed
conduit gripping spring, touching the spring generally at its
radially inner most convex surface, and at its radially outermost
concave surface. The gripping spring is configured in the conduit
fitting with the convex side toward the source of system fluid
elevated pressure. The gripping spring maintains some amount of
convexity toward the source of pressure, even after fitting
pull-up. As that pressure attempts to push the conduit out from a
pulled-up fitting, the inner diameter of the conduit gripping
spring embeds deeper into the conduit surface. This provision of a
greater grip in response to a greater pressure load to push out the
conduit is called an energized conduit grip, a grip that increases
to meet an increased conduit gripping requirement due to increasing
system fluid pressure.
[0048] Embodiments that use a spring-like washer for the conduit
gripping member 34 may be used to effect various advantages for the
fitting designer. The spring-like member 72 may be tightened to a
fully pulled-up condition as in FIG. 5 with a rather short stroke
or displacement of the nut 12 relative to the body 14. For example,
the embodiment of FIG. 1 may be fully made up with only a half-turn
or even a quarter-turn of the nut relative to the body. The use of
the generally flat gripping member(s) 34, even if more than one is
used in a stacked configuration, provides a compact fitting design.
The controlled deflection of the spring also facilitates the use
and design of these fittings for thin walled conduits, as well has
heavy walled conduits.
[0049] Turning now to FIG. 6, we further contemplate as one of our
inventions the realization of a `smart fitting`, meaning that a
fitting or assembly for a mechanically attached connection includes
a sensing function that may provide information or data to an
analytical function or process about the health, properties,
assembly, condition and status of the assembled fitting, one or
more of the fitting parts, the fluid contained by the fitting, or
any combination thereof. In the present disclosure, an embodiment
as illustrated in FIG. 6 includes a sensing function that is
incorporated into or otherwise associated with the seal element 48'
that is provided to form a zero clearance seal for the fitting 10.
We use the prime (') notation in FIG. 6 for the seal element
because the basic configuration and function of the seal element
48' may be but need not be the same as was used for the embodiments
of FIGS. 1-5. As will be readily apparent from the further
discussion below, additional or alternative sensing functions may
be introduced into the fitting 10, including many different ways to
structurally introduce sensing functions in the fitting.
[0050] The present inventions are not limited to any particular
fitting design or configuration, and also are directed to the idea
of introducing into or including with such fittings a sensing
function. Due to the sometimes highly complex and numerous uses of
fittings in a fluid system, it may be desirable to be able to sense
one or more conditions, or collect data and information, regarding
the assembly, performance or health of a fitting or the fluid
contained by a fitting or both. With so many fittings already in
use, easily numbering in the billions, the present inventions
provide apparatus and methods for introducing sensing functions
into an existing fitting design, an installed fitting design, or
providing a sensing function as part of a new fitting or fitting
installation, repair, retrofit or as part of a maintenance
operation. With the ability to provide ubiquitous and facile
installation of a sensing function with a fitting, the fluid system
designer may develop all different types of control and monitoring
systems 128 to utilize the data and information collected or
obtained right at the fitting site, including as needed on a
real-time basis. The control and monitoring system or circuit 128
may be conveniently disposed outside the fitting, even in a remote
location, and use wired or wireless communication links with the
sensor to receive the data and information provided by the sensor.
Alternatively, the circuit 128 may be integrated with the fitting
itself, such as on an exterior surface for example. By "remote" is
generally meant that the circuit 128 is away from the fitting, and
may be at a distance from the fitting, but the term is not intended
to imply nor require that it must be a great distance or even
beyond line of sight, although in some applications such longer
distance communication may be desirable, either in a wired or
wireless manner. Some sensors may be interrogated by circuits that
are handheld within a close remote location or range such as a foot
or less for example. An RFID tag is a common example of such a
device.
[0051] A fitting with a sensing function can be considered a `smart
fitting`, meaning that a fitting or assembly for a mechanically
attached connection includes a sensing function that may provide
information or data to an analytical function or process about the
health, properties, assembly, condition and status of one or more
of the fitting components, the fluid contained by the fitting, or
both. In the present disclosure, the exemplary embodiments as
illustrated herein include a sensing function that is incorporated
into or otherwise associated with a component or part or member of
the fitting, or added to a fitting by means of a sensor carrier or
substrate that is provided to position a sensing function in the
fitting to perform its designed function.
[0052] Although in the FIG. 6 embodiment the sensing function is
associated with the seal element 48', those skilled in the art will
readily appreciate that one or more sensors and sensing functions,
whether wetted or non-wetted type sensors, may alternatively or in
addition to the seal element sensor, be associated with other
fitting members such as, for example, the drive member 36, the face
seal member or gland 40, the nut 12, the body 14, the conduit
gripping member 34 or even the conduit C. As an example, we show a
sensor 120c associated with the face seal member or gland 40 (FIG.
6). The seal element 48' does provide a simple and fast way to
introduce a sensing function into a fitting, whether the fitting is
a new assembly, an assembly already installed in a fluid system, or
for retrofit, repair or maintenance. Use of installable sensing
functions allows a designer to provide a common fitting design that
can be made "smart" simply by introducing the sensing function into
an installable component such as the seal element for example. For
example, even after a fitting has been installed into a fluid
circuit, the fitting can be made smart by introducing one or more
sensors into the fitting, can have one or more sensors removed, or
have different sensors added or removed. For example, internal
sensors may be installed by first disassembling a tightened fitting
sufficiently to gain access to whatever structure is needed to
install a sensor, such as for example swapping out a sensor-less
gasket for a gasket having a sensor. Or perhaps the installer may
decide to add an external or internal temperature or pressure
sensor when it is discovered that temperature or pressure sensing
is needed that was not known before at a particular fitting or
location in the fluid circuit. These are just a few examples of the
many options made available by the inventions herein by having
fitting designs that facilitate use of sensing functions with the
fitting.Use of a sensing function in an installable part also
facilitates postponement of final fitting configuration to the
field, which allows for more efficient inventory control since an
end user would not need to stock both "smart" and regular fittings.
Alternatively or additionally, the sensing function may be
incorporated into or integrated with one or more of the various
parts of the fitting.
[0053] In the exemplary embodiment of FIG. 6, the seal element 48'
may include one or more sensors 120 that are attached to,
integrated with or otherwise associated with the seal element 48'.
The sensors 120 may take a wide variety of forms and functions.
Each sensor 120 may be a wetted sensor 120a meaning that a portion
of the sensor is exposed to the system fluid passing through the
fitting 10, or a non-wetted sensor 120b that is not exposed to the
system fluid, or a combination thereof. A sensor may be used, for
example, to sense, detect, measure, monitor or otherwise collect
information or data about a property or characteristic of the
mechanically attached connection, for example, general leakage,
conduit bottoming, changes in stress, or vibration to name a few
examples; of one or more fitting components such as the coupling
components, conduit gripping member(s), seals and so on; and/or the
fluid contained by the mechanically attached connection or fitting,
or any combination thereof. A wetted sensor 120a may sense, for
example, pressure, temperature, galvanic effects, fluid density,
refractive index, viscosity, optical absorbance, dielectric
properties, flow rate, conductivity, pH, turbidity, thermal
conductivity, moisture, gas or liquid specific properties and so on
to name a few examples. Examples for a non-wetted sensor 120b may
include, pressure, temperature, seal integrity, leakage, leak rate,
stress and stress profiles, vibration, tube bottoming and so
on.
[0054] The zero clearance fitting concept herein provides an
exemplary structure for optionally introducing a sensing function
into a mechanically attached connection. This allows the designer
to incorporate a sensing function when needed or to omit the
sensing function by either not connecting to the sensor or using a
seal element that does not include a sensor in its structure. This
allows a sensing function then to be added into a fluid system even
after a non-sensor fitting has been installed, simply by replacing
the seal element 48 with a seal element 48' having the sensing
function associated therewith. By having a fitting design, whether
zero clearance or not, that may optionally receive a sensing
function, the end user may decide which fittings will be smart,
thus allowing postponement of final fitting configuration to the
field. Such postponement may offer significant advantages in terms
of inventory management and design optimization for the fluid
system.
[0055] It should be noted that the locations of the sensors 120a,
120b illustrated are exemplary and will be selected as a matter of
design choice based on what the sensor function and configuration
will be. Additionally, the sensors may be embedded in the seal 48'
body or surface mounted or otherwise attached or integrated with
the seal 48'. For example, the non-wetted sensor 120b may be
recessed in a surface such as with a counterbore of the seal 48' so
that it can measure stress or pressure of the conduit end CI
against the seal pocket 64 to detect or sense bottoming of the
conduit C in the fitting.
[0056] The sensors 120 may operate in many different ways,
including but not limited to electromagnetic, acoustic-magnetic,
magnetic resonance, inductive coupling including antenna, infrared,
eddy current, ultrasonic and piezoelectric. The sensors 120 may
communicate in a wired or wireless manner with the latter including
but not limited to BLUETOOTH.TM., Wi-Fi, 2G, 3G, RFID, acoustic,
infrared, and optical. In the FIG. 6 embodiment, the sensors 120
are wired. Recesses or passages 122 may be formed in the seal 48'
through which wires or conductors or other communication links 124
such as optic fibers may be routed out of the fitting 10. The
threaded nut and body connection may include a groove or axial hole
or other path 126 positioned below the minor diameter of the
threads to allow the communication link to be routed outside the
fitting 10 to electronics 128 that will process the sensor
information and signals.
[0057] The sensors 120 may be incorporated into the seal 48' by any
number of suitable techniques, including but not limited to
adhesive, painting, embedding, sputtering, metal injection molding,
casting, compression, etched, printed and so on.
[0058] There is a wide variety of sensors commercially available
today that may be used for various sensing functions. Undoubtedly,
many more sensors will be developed and commercialized during the
coming years, especially sensors that will have greater
functionality, significantly small footprints, alternative
installation and integration capabilities and communication
functionality. The present inventions contemplate and facilitate
the use of such sensors known today or later developed, in fittings
as described herein.
[0059] Examples of commercially available sensors include but are
not limited to the following: Micro-miniature absolute pressure
sensor model 32394 available from Endevco Corporation. This is a
silicon MEMS device that can be substrate or surface mounted with a
conductive epoxy. Another pressure sensor or transducer is the
model 105CXX series available from PCB Piezotronics, Inc. These
sensors are in very small packages or may be re-packaged as needed
for a particular application, and operate with piezoelectric
technology. Liquid flow meters such as models SLG 1430 and ASL 1430
available from Sensirion AG. Miniaturized seismic transducers,
motion transducers and angular rate sensors available from Tronics
Microsystems SA. Tilt and vibration sensors, angle sensors, MEMS
inclinometers, MEMS vibration sensors and MEMS accelerometers
models SQ-SENS-XXXX, SQ-SIXX, SQ-PTS, SQ-SVS and SQ-XLD
respectively, available from Signal Quest, Inc. Piezoelectric
accelerometers model TR1BXN having temperature sensing capability,
available from OceanaSensor, Virginia Beach, Va. Thermal sensors
models LM and STXXX (numerous variations) available from ST
Microelectronics. Thermistors, IR temperature sensors, gas tube
arresters and varistors available from Semitec USA Corporation.
Linear displacement sensors models M, MG, S, SG and NC type DVRTs
available from MicroStrain Inc. Proximity switches available from
COMUS International.
[0060] The above are but a few examples of miniaturized sensors
available that may be used with the present inventions. The present
inventions facilitate and enable such sensor technology to be
incorporated into fittings and mechanically attached connections.
Reference may be made to the manufacturer's web pages for
additional product information. While the basic product literature
may illustrate specific packaging concepts, the sensors may be
either repackaged or alternatively integrated with a fitting
component or member in accordance with one or more of the various
inventions herein.
[0061] SENSOR INTEGRATION, WETTED--The sensors 120 may be embedded
on the wall surfaces of the seal element 48'. Embedding methods may
include but are not limited to resin potting, powder metal
sintering, or brazing. Wetted sensors 120a may be used to monitor
fluid system pressure, temperature, and other fluid parameters. As
another example, a wetted sensor may be used as a flow sensor. In
the flow sensor case, small wetted flow sensors are available from
Sensirion. Flow sensors may utilize tuned conduit geometry, such
as, for example, including a tuned insert into the fitting. Sensors
120 placed on the wetted surfaces of end fitting tube sockets 64
may also be used to monitor tube bottoming and extent of fitting
pulled-up condition. For example, a proximity sensor may be used to
detect conduit bottoming or also position of the conduit gripping
device or devices to verify pull-up. A wetted sensor can be paired
with another sensor (not shown), a non-wetted sensor for example,
to facilitate a wireless communication from the first sensor to the
other sensor. In other alternative embodiments, wireless wetted
sensors may be disposed or integrated with wetted surfaces of the
various fitting components, and wirelessly communicate through a
wall of the component. This may avoid the need to breach the
pressure containment structure of the fitting. But in lower
pressure or benign applications, wired sensors that do breach the
pressure containment structure may be used. This concept may be
applied not only to non-metal components, but also metal components
including but not limited to 316 stainless steel. The component
material will in part determine the wireless frequency needed,
along with the thickness of any wall that the wireless signal must
penetrated to be picked up by appropriate electronic circuits that
receive and process the wireless signals. As still another
alternative, miniature microphones and accelerometers from Akustica
may be used in the fitting to detect vibration, leakage or the
onset of leakage when variations in the acoustic signatures are
detected.
[0062] SENSOR TECHNOLOGY--The sensors 120 may comprise a film that
is pressure sensitive and changes color with changes in pressure.
Photonics sense the color, the indication of pressure, and an optic
fiber or other device may be used, for example, for sensor signal
transmission to the electronics 128. The sensors 120 may
alternatively comprise a force sensitive molecular structure which
has a characteristic resonance that is proportional with applied
force. That resonance can be detected by a remote scanner for
example, such as a RF wand. The sensors 120 may alternatively
comprise a dual diaphragm for detecting a spaced differential of a
physical property (e.g. pressure differential, strain differential,
capacitance). A common detection technique may be use of photonics
that sense both diaphragms and detects a response difference
(reflection, refraction, or intensity shift) proportional to
physical property differentials or change in the diaphragms.
[0063] The sensors 120 may be integrated onto the wetted surfaces
of the generally circular ring or hoop-like seal element 48'. The
sensors 120 may be integrated onto the seal 48' inside diameter
surfaces or on radial surfaces that when assembled in the fitting
10 will be wetted by system fluids. The sensor elements may be
laminated, printed, attached, adhesively applied or equivalently
applied or otherwise applied directly to the seal 48' surfaces. The
seal 48' may comprise a split-ring assembly or seal insert to
enable direct printing or applying of sensor elements to the seal
element inside diameter surfaces. Where axial orientation of the
sensor is important, for example sensors for fluid flow, these seal
inserts may be keyed to axially differentiated slots or grooves on
the seal. The seal 48' may be keyed directionally using
counterbores, circumferential shoulders, or the like to match
directionally keyed structures on the fittings, particularly face
seal fittings. The sensors 120 that are integrated into the seal
48' may be hard wired connected to the electronics 128 or other
sensors or both, and thus may comprise leads or equivalent to
external surfaces to hard wire the sensor from outside the
containment of system fluids. Such leads form a composite with the
seal such there is no compromise of system fluid containment or
seal integrity. Sensors integrated into the seal 48' may comprise
leads or equivalent to provide external antenna for the sensors.
Here also, such leads form a composite with the seal such there is
no compromise of system fluid containment or seal integrity.
Sensors integrated into seals, whether fully passive or powered by
built-in battery or fuel cell, may alternatively comprise no leads
to external surfaces, and thus no compromise of system fluid
containment or seal integrity.
[0064] The inventions herein include methods for mechanically
connecting a conduit to another fluid member, with the methods
fully set forth above in the description of the exemplary
embodiments. One such method comprises connecting a conduit to a
fluid member by forming a conduit gripping connection and a zero
clearance seal in an exemplary manner as set forth above. In
another embodiment, the method may include providing a sensing
function that is associated with the zero clearance seal.
[0065] The electronics 128 (FIG. 6) may be operably coupled to the
sensors 120 in many different ways, including wired and wireless
connections. Wireless connections may include electromagnetic
coupling such as by antenna, or optical coupling, acoustic and so
on. The specific circuits used in the electronics 128 will be
selected and designed based on the types of sensors 120 being used.
For example, a strain gauge may be used for a non-wetted sensor
120b, and the strain gauge will exhibit a change in impedance,
conductivity or other detectable characteristic or condition. The
electronics 128 may provide a current or voltage or other energy to
the strain gauge, across a wired connection or wireless connection
for example, so as to detect the strain gauge condition of
interest. Similarly, the electronics 128 may interrogate or detect
a temperature or pressure sensor condition, or the electronics 128
may receive signals transmitted from the sensor that encode or
contain the information or data of interest produced by the sensor.
These are just a few examples of the wide and extensive variety of
sensors and electronics that may be used to carry out the
inventions herein.
[0066] With reference to FIG. 7, the drawing illustrates one
example of many different types of a fitting 2010 that may be used
with one or more of the present inventions. In particular, FIG. 7
illustrates a flareless compression fitting that uses a smart
fitting concept of incorporating one or more sensors into the
fitting. Such uses of sensors as illustrated in FIG. 7 may also be
used with the zero clearance type fittings described herein. The
fitting 2010 typically includes a nut 2016 that may be joined with
a body 2012 such as, for example, with a threaded connection 2014,
2018. One or more compression type ferrules 2020, 2022 may be used
to seal and hold a conduit end such as a tube or pipe end so as to
form a leak tight flow path from the conduit to another flow path,
in this case through the body 2012. The fitting illustrated in the
drawing is commonly referred to as a female fitting in that the
body 2012 is a female threaded component that joins with the male
threaded nut 2016. Alternatively, as is well known, male fittings
are commonly used that have a male threaded body and a female
threaded nut. Non-threaded connections may alternatively be used as
well. In accordance with the present disclosure, one or more of the
fitting components including the body, nut, the ferrules and the
conduit end, may be provided with one or more of electrical,
electro-magnetic or electronic capability, such as for example a
sensor or element 2100, that facilitates manufacture, assembly or
use of the fitting. The component 2100 may be surface mounted,
embedded, etched or otherwise associated with a fitting component
as needed for a particular application.
[0067] SENSOR INTEGRATION--(a) Sensors are applied to the surfaces
of fitting components--e.g. to the fitting body, ferrule or
ferrules, nut, tube adaptor, or tube end. Application methods for
applying sensors can include sticking, gluing, painting, plating,
or in coatings of any type. (b) Sensors are embedded in fitting
components. Embedding methods can include resin potting, powder
metal sintering, or brazing. (c) Sensors are made concurrently
integral to fitting components, as the components are manufactured.
Such concurrent methods can include metal injection molding,
casting, or compression and injection molding in the case of
plastic fitting components. Concurrent methods can also include
sensor placing or embedding at regular intervals on or in bar
stock, such that one or more sensors remain in each machined
component. (d) Sensors may be chipless in the sense that they are
printed, etched, sputtered, or likewise marked onto fitting
components. Such marking methods can include application of sensor
circuitry material to the component, making use of the component
material substrate. Marking methods may not necessarily use silicon
applications. Marking methods can also include use of electrical
conductor altering properties of a diffusion modified near surface
of the component, doping elements within the component alloy or
material, or dispersed or localized second phases within the
component material. (e) Sensors are integrated with fitting design.
Such integration can include access ports to aid sensor powering or
data query, whether by electro-magnetic effects, acoustic-magnetic
effects, magnetic resonance, inductive coupling, IR, eddy current,
surface acoustic waves, or ultrasonic.
[0068] SENSOR APPLICATIONS--(a) Sensors applied to components
provide component history, QA/QC information, source tracing back
to the manufacture of the raw material melt or equivalent. (b) With
use of a central registry, sensors guard against and detect
incidence of component intermix or component counterfeiting. (c)
Sensors provide data specific to the fitting--e.g. product ratings,
codes and standards, material and fluid compatibilities, and
installation instructions. (d) Sensors provide feedback on the
condition or success of fitting installation in a fluid
system--e.g. ferrule order, tube bottoming, turns of the nut. Such
feedback can be coupled with visual, color codes, vibrating,
audible or voice devices for immediate access to fitting specific
data and indication of installation condition. Such feedback can
also include both self diagnostics and suggested remedies. (e) In
use, sensors provide indication of changes in the
installation--e.g. nut turning, tube slippage, component removal,
corrosion effects, any other impending dysfunction, as well as
successful ferrule or component response adapting to a changing
fluid system. (f) In use, sensors provide measurement of fluid
system and fluid state parameters--e.g. pressure, temperature,
fluid properties, fluid flow rate, or system vibration. Sensors can
relate such measurements to applicable agency codes, standards,
product ratings, and can warn if exceeding allowed ratings or
levels. Fluid flow methods can include IR signal processing. (g) In
use, sensors detect fluid leaks and provide indications of leak
rate, as well as confirmation of successful fluid sealing. Leak and
seal detection methods can include ultrasonic signal
processing.
[0069] SENSOR TECHNOLOGY--(a) Sensor are wired or wireless. Sensors
can include the fluid system tubing in the sensor circuitry. If
wired, this can include use of fluid system tubing for sensor
powering or signal transmission. If wireless, this can include use
of the system tubing as antenna. In both cases, sensors can use the
position of tubing in the fitting as part of circuitry indicating
successful tube position during and after installation. (b) Sensors
are powered or passive. If powered, sensors can use batteries or
miniature fuel cells. They can draw direct external electrical
power or draw power through use of electro-magnetic field effects,
magnetic resonance, inductive coupling, infrared (IR), eddy
current, surface acoustic waves or ultrasonic. Sensors can also
draw power from the environment--e.g. changes in temperature,
system fluid flow, static charge build-up, system vibration, or
galvanic effects of locally dissimilar materials. If passive,
sensors are powered by incoming query from an external device. Such
queries can use any of the above methods for the continuous
powering of powered sensors. (c) Sensors use present or emerging
signal processing and communication protocols. If wired, protocols
include 4 to 20 m-amps. If wireless, protocols include WiMax, 3G or
2G cellular, Wi-Fi, Bluetooth, Zigbee, Ultra Wide Band, or RFID.
Protocols can also include use of mobile phones or equivalent
mobile reader devices to collect data and communicate with a
central registry. Such mobile reader devices can be integrated into
the tools used for fitting pull-up. (d) Sensors are piezoelectric
or respond similarly to mechanical deflection or strain. Applied on
or in fitting components, sensors respond to fluid system
parameters--e.g. pressure, vibration, ultrasonic effects of fluid
leaks--as well as extent of fitting pull-up during or after
installation.
[0070] Smart fitting applications include, as examples: [0071] (1)
Installed Fitting Health--Sensors in the fitting components measure
conduit and component loads and relative positions as measures of
both initially sufficient and sustained-in-use installed fitting
pull-up. Sensor types include micro-strain, proximity,
vibration/acceleration, ultrasonic and cycle count. [0072] (2)
Installed Fitting Seal Integrity--Sensors in the components of
installed fittings measure incidents of seal leakage of system
fluids. Sensor types include ultrasonic and chemical detectors.
[0073] (3) System Fluid Measurement--Sensors in the components of
installed fittings measure the characteristics of system fluids.
Sensor types include temperature, pressure, flow, density,
refractive index, viscosity, optical absorbance, dielectric
characteristic, conductivity, pH, turbidity, thermal conductivity,
moisture and chemical specie. [0074] (4) Integrated
Sensors--Sensors attach to fitting components by methods including
direct printing or fabrication on the component surface, on gaskets
or inserts that assemble into and between fitting components.
[0075] (5) Sensor Communication--Sensors are wireless and passive,
both wetted and non-wetted by system fluids. Wetted sensors
communicate through the system fluid containing walls of the
fitting components without antenna or wires that breach the fluid
containing walls. Wetted sensors also have known chemical
compatibility, duty cycle and failure mode. [0076] (6)
Traceability--Sensors (e.g. RFID) in the fitting components provide
fitting and component characteristics including identity,
serialization and code compliance.
[0077] With reference to FIGS. 8-10, we illustrate another
embodiment of a zero clearance fitting 200. The fitting 200 may
include a first coupling member or body 202 and a second coupling
member or nut 204 that are joined together during pull-up of the
fitting. In this embodiment the body and nut may be threadably
joined as with a threaded connection 206. The body 202 may further
include a planar end face 208 that also forms or provides a face
seal surface for a zero clearance face seal arrangement 210. The
body 202 may itself be considered a fluid member that is connected
to the conduit end C, or may include an end configuration 216 that
may be further connected to another part. As shown, the end
connection 216 of FIG. 8 may include a male threaded end 218 of a
conventional tube fitting body, but any end connection
configuration may be used as needed to connect the conduit end C
into the fluid system or to another fluid member. The body 202 may
also be integrated into or with another device such as a fluid
control device, such as for example a valve, flow mater, tank and
so on to name just a few examples.
[0078] Although this embodiment provides for a threaded connection
between the first and second coupling components 202, 204, threaded
connections are only one of the many available choices.
Alternatives include but are not limited to clamped or bolted
connections. The type of connection used will be determined by the
nature of the force needed to secure the assembly 200 to the
conduit end in a fluid tight manner. Generally speaking, a fitting
such as illustrated in FIG. 8 may be used for a flareless end
connection, meaning that the conduit cylindrical shape is not
flared as a processing step prior to connection to another fluid
member (although the conduit may plastically deform during the
installation process). The conduit end does not require any
particular preparation other than perhaps the usual face and debur
process for the end surface C1.
[0079] In many respects, the fitting 200 functions in a similar way
to the embodiments of FIGS. 1 and 6. However, rather than a spring
type conduit gripping member, the fitting 200 may use a gripping
member 220 that is an annular ring like device such as, for
example, a ferrule or multiple ferrules. The gripping member 220
may include a continuous cylindrical interior wall 220a closely
received over the conduit C outer surface C2, and that extends
completely through the device, or may have various contours,
recesses and so on as needed for a particular application. A face
seal insert 222 cooperates with the gripping member 220 and the
second coupling member 202 to effect conduit grip and fluid tight
seals. However, in this embodiment (as contrasted with the
embodiment of FIG. 1 for example) the insert 222 is a single piece
that performs both the face seal function and receives the conduit
end C in a conduit end socket.
[0080] The insert 222 may be an annular part having a first
interior cylindrical wall 224 and a second interior cylindrical
wall 226. The diameter of the first wall 224 is somewhat less than
the diameter of the second interior wall 226 so that a shoulder 228
forms a socket into which the conduit end C1 is received. During
assembly and tightening (pull-up) of the fitting 200, the conduit
end C1 should bottom against the shoulder 228. The insert 222 may
also be provided with an annular sealing bead or ring 230 that
contacts the planar end facing seal surface 208 of the first
coupling member 202. During pull-up of the fitting, the bead 230 is
compressed against the seal surface 208 to form a fluid tight seal.
The bead 230 may be less hard than the surface 208 so that the bead
is somewhat flattened, as illustrated in FIG. 9.
[0081] The first and second interior walls 224, 226 may be joined
by a somewhat tapered wall portion 232. This causes an inward
radial compression of the conduit end C1 during pull-up to help
retain the conduit in the socket and also may form a fluid tight
seal.
[0082] The insert 222 may also include a rearward axial cylindrical
extension 234 having an outer surface portion 234a that engages a
tapered surface 236 of the second coupling member 204. Relative
axial movement between these surfaces causes a radial inward
compression of the extension 234 (see FIG. 9) so that the extension
end or lip 234b is bent or deforms around the gripping member 220
upon complete pull-up. Because the gripping member 220 remains
attached to the conduit after pull-up, even when the first and
second coupling members are thereafter separated, the insert 222
will remain assembled to the conduit as well. In addition, as the
extension 234 slides or cams against the tapered surface 236, the
torque required to tighten the fitting 200 will increase
significantly, facilitating a pull-up by torque function. Thus, the
fitting 200 is amenable to pull-up by torque or pull-up by counting
turns of rotation of the second coupling member 204 relative to the
first coupling member 202.
[0083] The second coupling member 222 may also have a
frusto-conical surface 238 which engages a tapered wall 240 of a
nose portion 242 of the gripping member 220. Preferably, although
not necessarily, the frusto-conical surface 238 is formed at an
angle .alpha. relative to the longitudinal axis of the fitting 200,
with the angle .alpha. in the range of about 35 degrees to about 60
degrees, preferably about 45 degrees.
[0084] The gripping member 220 may include a reverse tapered outer
surface 244 so that when the gripping member 220 is axially
compressed into the socket defined by the extension 234, the bent
lip 234b will have adequate room to compress without strongly
compressing the rearward portion of the gripping member 220. The
gripping member 220 further includes a driven surface or back end
246 that engages with a drive surface 248 of the second coupling
member 204 during pull-up.
[0085] With reference then to FIG. 9, we illustrate the fitting 200
in a pull-up condition. The gripping member 220 has plastically
deformed with a forward edge 250 having indented into the conduit C
outer surface to form a shoulder 252. This engagement between the
forward edge 250 and the shoulder 252 provides very strong conduit
grip against pressure and may also form a fluid tight seal. The
conduit gripping member 220 deformation may further include the
cylindrical interior wall 220a deforming to a convex portion 254.
The convex portion may be contiguous to the front edge 250 or may
be axially spaced there from, but in either case the convex portion
254 swages or collets or accompanies an action that swages or
collets against the conduit outer surface (with either plastic or
elastic deformation of the conduit as needed) to provide a radial
stress into the conduit which isolates vibration effects from the
high stress region or stress riser that forms in the area where the
front edge 250 bites into the conduit. Still further, the camming
action of the gripping member nose portion 242 against the
frusto-conical surface 238 produces a metal to metal seal. When the
angle .alpha. is about 45 degrees, the compression of the nose
portion 242 against the camming surface 238 is akin to a coining
action.
[0086] After the fitting 200 has been tightened, it may be
disassembled by simply loosening the second coupling member 204
with respect to the first coupling member 202. Because the conduit
end C1 does not extend into the first coupling member 202, when the
second coupling member 204 is separated back from the first
coupling member 202, the fitting can be separated radially without
axial displacement of the conduit relative to the first coupling
member, thus making the fitting 200 a zero clearance fitting.
[0087] Alternatively, the gripping member 220 need not actually
bite into the conduit and there need not be a swage or collet
effect produced, such as for fittings that will not be expose to
vibration or elevated pressures, for example. As another
alternative, various parts or surfaces of parts may be hardened to
effect metal to metal seals. For example, the facing seal surface
208 may be hardened relative to the bead 230 which will result in
the bead flattening and also produce an effective metal to metal
seal. Also, the gripping member 220 may be case or through hardened
so that it can bite into hard conduit materials as well as form the
seal against the camming surface 238. Any suitable hardening
process may be used for the various surfaces or parts, including
but not limited to low temperature carburizing, work hardening and
so on as are well known to those skilled in the art. The use of
hardened surfaces to enhance the metal to metal seals and tube grip
may be used with any of the embodiments described herein.
[0088] All of the zero clearance exemplary embodiments illustrated
or described herein may optionally include one or more sensors or
sensing functions, such as for example illustrated in FIGS. 6 and 7
herein, or others, including different positioning of the sensors
within the various fitting components.
[0089] With reference to FIGS. 10-15, we illustrate additional
optional and alternative designs and features for the zero
clearance fittings of FIGS. 1 and 10 herein. For clarity and ease
of explanation, for these various embodiments we only illustrate
the enlarged half view in longitudinal cross-section of the
coupling area of the fittings, similar to the views of FIGS. 2, 6
and 10 for example. It will be readily understood by those skilled
in the art that each complete fitting is symmetrical about the
central longitudinal axis X and may, but not necessarily needs to,
have similar first and second coupling member designs as the FIGS.
1, 6 and 8 embodiments, or different designs for the first and
second coupling members. We also only show the fittings in a finger
tight condition, it being understood that during pull-up the
gripping members may deform in a similar way, or alternatively may
deform in a manner needed for a particular application. All of
these embodiments may also have hardened surfaces or parts as
needed, as well as sensing functions incorporated therewith.
[0090] In the FIG. 11 embodiment, the fitting 300 may be similar to
the embodiment of FIG. 10, and like reference numerals are used for
like parts or structural features. It should be noted however, that
the exact same parts need not be used for all applications, as
demonstrated by the variations of these alternative embodiments.
Thus, there is a first coupling member having a facing end surface
208 that functions as a zero clearance face seal surface. An insert
222 includes a sealing bead 230 that forms a zero clearance face
seal against the surface 208 upon pull-up. The insert 22 also
includes a conduit end socket formed by a shoulder 228. A second
coupling member 204 is joinable to the first coupling member such
as, for example, with a threaded coupling 206 or other suitable
arrangement. A conduit gripping member 220 is provided.
[0091] In comparing FIGS. 11 and 10 it will be noted that an
additional piece is included, in the form of a retaining cup or
ring 302. This retaining piece 302 is a hollow somewhat flexible
member that can slideably receive the conduit end C1 and is
inserted into the second coupling member 204 before the conduit
gripping member 220. The insert 222 includes a modified rearward
portion that omits the extension 234 in the FIG. 10 embodiment. The
insert 222 includes the frusto-conical camming surface 238, but
further includes a notch, recess or groove 304 in its outer
surface. The retaining ring 302 at its outer end includes one or
more fingers or projections 306 that are received into the recess
304, such as for example with an optional noticeable click or snap.
In this manner, in the finger tight condition, or even before the
conduit end C1 is inserted into the second coupling member 204, the
retaining ring 302 functions to hold the coupling member 204, the
insert 222 and the gripping member 220 together as a preassembled
component or cartridge. This can greatly simplify final assembly in
the field, as the user only needs to mate up the preassembled
cartridge with the first coupling component 202 after the conduit
end has been inserted (thus providing a two piece fitting as far as
the user is concerned, having zero clearance). To further aid in
keeping the preassembly together, the retaining ring may optionally
have a stiffer rearward body portion 308 that snugly engages into
the socket of the second coupling member.
[0092] The retaining ring 302 may be a cup like element that is
solidly annular, or the fingers 306 may comprise a plurality of
extensions from the body 308. The recess 304 may likewise be
continuous about the circumference of the insert 22 or may be
provided in two or more sections.
[0093] In the embodiment of FIG. 12, another zero clearance fitting
350 comprises various parts that may be of similar design to the
FIG. 11 embodiment, except that it will be noted that the retaining
ring or cup is no longer used. Instead, in this embodiment, an
annular retainer or sleeve 352 is provided. This sleeve may be
somewhat compressible and fits between the recess 304 and an inner
cylindrical wall 354 of the second coupling member 204. The sleeve
352 may provide an interference fit between the insert 222 and the
second coupling member 204 so as to retain as a preassembly or
cartridge, the second coupling member 204, the gripping member 220
and the insert 222. The sleeve 352 may be made of any suitable
material, and may be non-metal as it is not needed for any seal or
structural function other than to hold the preassembly together
from the factory to the field.
[0094] In the FIG. 13 embodiment, another zero clearance fitting
400 comprises various parts that may be of similar design to the
FIG. 10 embodiment, except that it will be noted that the rearward
extension has been modified. In this embodiment, the insert 222 is
provided at its rearward portion with a thin flexible extension
402. The extension 402 may be in the form of an annular continuous
cup, or may be realized as one or more fingers or ribs that extend
rearward, such as for example, from the frusto-conical camming
surface 238. This retaining feature 406 of the extension 402 and
lip 404 may include an inward lip 404 that slides over and against
the outer surface 244 of the gripping member 220. In this way, the
retaining feature 406 may be used to hold the insert 222, gripping
member 220 and second coupling member 204 together as a preassembly
or cartridge for shipment to the field or end user. For example,
there may be provided an interference or snug fit of the gripping
member 220 inside the second coupling member 204, or alternatively
an adhesive may be used to retain the parts together or other
structure may be added to foam the preassembly. Moreover, the
insert 222 and gripping member 220 may together be considered as a
preassembly.
[0095] The FIG. 14 embodiment of a zero clearance fitting 450 is
similar in most respects to the FIG. 13 embodiment, except that in
addition the gripping member 220 may be provided with a notch or
relief 452 in its outer surface 454, that cooperates with the
extension 402, and more specifically with the lip 404, to function
as the retaining feature 406. In this way, the retaining feature
406 may be used to hold the insert 222, gripping member 220 and
second coupling member 204 together as a preassembly or cartridge
for shipment to the field or end user. For example, there may be
provided an interference or snug fit of the gripping member 220
inside the second coupling member 204, or alternatively an adhesive
may be used to retain the parts together or other structure may be
added to form the preassembly. Moreover, the insert 222 and
gripping member 220 may together be considered as a
preassembly.
[0096] With reference to FIG. 15, we illustrate another embodiment
of a zero clearance fitting 500. This embodiment has many
similarities to the embodiment of FIG. 1, but with some significant
differences as will be further explained herein. The fitting 500
may include first and second coupling members 512, 514 which may be
the same or different from the coupling members 12, 14 of the FIG.
1 embodiment. The coupling components 512, 514 may be threadably
coupled as at 515, but may be joined by any other technique as
needed. The second coupling member 514 may include an annular zero
clearance face seal surface 514a.
[0097] A generally annular face seal member or insert 516 includes
a face seal surface 518 on one end, and a frusto-conical surface
520 on an opposite end. The insert 516 further may include a
cylindrical interior wall portion 522 and an optional tapered
interior wall portion 524. The conduit end C1 is closely received
by these interior wall portions. The conduit end C1 after pull-up
is radially compressed by the tapered wall 524 and may form a fluid
tight seal therewith.
[0098] A conduit gripping member 526 that may be an annular ring
like device such as, for example, a ferrule. The gripping member
526 may include a continuous cylindrical interior wall 526a closely
received over the conduit C outer surface C2, and that extends
completely through the device, or may have various contours,
recesses and so on as needed for a particular application. The
gripping member 526 also has a rear wall portion 528 that is a
driven surface that contacts a drive surface 530 of the first
coupling member 512. The gripping member 516 may also include a
tapered nose portion 532 that engages and cams against the
frusto-conical surface 520 during pull-up of the fitting 500. The
gripping device 526 may but need not deform during pull-up in a
similar manner to the gripping device of the FIG. 9 embodiment.
[0099] A seal member 534 may be disposed between the insert 516 and
the zero clearance end face 514. This seal member may be similar in
design and function as the seal member 48 in the FIG. 1 embodiment.
However, because the insert provides a conduit end socket formed by
the cylindrical walls 522, 524, the seal member 534 does not
include a radial inward extension, although alternatively it may.
The seal member 534 may include first and second annular sealing
beads 536, 538 that respectively are compressed against the seal
surfaces 514a and 518.
[0100] It should be noted for all the embodiments that use sealing
beads and so on, the beads may alternatively be formed on the
facing surfaces so that the seal member presents planar seal
surfaces. Also, the sealing beads may be in a shape and size that
is different from the illustrated embodiments. In still a further
embodiment, the insert 516 and the seal element 534 may be formed
as a single piece part, similar for example to the embodiment of
FIG. 14 herein.
[0101] Additional and optional features of the embodiment of FIG.
15 is the provision of a retaining feature 540 in the form of an
annular extension 542 rearward from the main body of the seal
member 534. This extension 542 may include a lip 544 or similar
protrusion that cooperates with a lip 546 formed at one end of the
insert 516. This insert lip 546 may be formed as part of providing
a circumferential recess or notch 548.
[0102] The insert 516 may also include an optional rearward
extension 550 from the frusto-conical surface 520, much in the same
manner as the extension illustrated in FIGS. 13 and 14 herein. This
extension 550 may include a lip 552 that engages with the gripping
member 526 so that the gripping member 526, the insert 516 and the
seal member 534 may be assembled as a preassembly or cartridge.
This preassembly may also be installed in the first coupling member
512 for a two piece fitting construct to be assembled later in the
field or by an end user. The gripping member 526 may optionally be
provided with a notch (not shown) as used in the embodiment of FIG.
14 to cooperate with the lip 552.
[0103] The drive surface 530, as well as the driven surface 528,
may be contoured or shaped other than as a frusto-conical shape as
illustrated herein to facilitate tightening of the fitting during
pull-up. This may apply to all the gripping member designs
described herein. In the FIG. 15 embodiment, the drive surface has
a first section 530 and a second section 554 with a shallower
taper. This additional section may assist in the gripping member
releasing from the first coupling member during disassembly.
Alternatively, the drive surface 530 may be a single continuous
angle surface (not shown).
[0104] In the various alternative embodiments described herein with
respect to FIGS. 10-15, the fittings will be pulled-up and function
in a manner similar to the earlier described embodiments herein,
especially as to conduit grip, fluid tight seal, reduced vibration
sensitivity, preassembly, postponement, re-make capability and so
on.
[0105] The inventive aspects have been described with reference to
the exemplary embodiments. Modification and alterations will occur
to others upon a reading and understanding of this specification.
It is intended to include all such modifications and alterations
insofar as they come within the scope of the appended claims or the
equivalents thereof.
* * * * *