U.S. patent application number 14/518613 was filed with the patent office on 2015-04-23 for roll formed conduit fitting.
This patent application is currently assigned to Tylok International, Inc.. The applicant listed for this patent is Lawrence Hahn, Keith Kainec, Don Levengood, Vincent Traina. Invention is credited to Lawrence Hahn, Keith Kainec, Don Levengood, Vincent Traina.
Application Number | 20150107323 14/518613 |
Document ID | / |
Family ID | 52824979 |
Filed Date | 2015-04-23 |
United States Patent
Application |
20150107323 |
Kind Code |
A1 |
Traina; Vincent ; et
al. |
April 23, 2015 |
ROLL FORMED CONDUIT FITTING
Abstract
A tool roll forms an end of a thick walled conduit so that a
conventional compression fitting may be used. The tool can include
a forming roller with two ridges to make two ferrule-receiving
seats in the conduit and a pair of edges forming witness lines that
indicate when the seats have been fully formed by the tool. In
addition the witness lines are located to show when a conduit had
been fully inserted into a fitting and when the fitting has been
fully made up.
Inventors: |
Traina; Vincent; (Concord
Township, OH) ; Hahn; Lawrence; (Greenville, SC)
; Kainec; Keith; (Sagamore hills, OH) ; Levengood;
Don; (Chagrin Falls, OH) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Traina; Vincent
Hahn; Lawrence
Kainec; Keith
Levengood; Don |
Concord Township
Greenville
Sagamore hills
Chagrin Falls |
OH
SC
OH
OH |
US
US
US
US |
|
|
Assignee: |
Tylok International, Inc.
Euclid
OH
|
Family ID: |
52824979 |
Appl. No.: |
14/518613 |
Filed: |
October 20, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61893278 |
Oct 20, 2013 |
|
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|
Current U.S.
Class: |
72/112 |
Current CPC
Class: |
B21H 1/18 20130101; B21H
7/182 20130101 |
Class at
Publication: |
72/112 |
International
Class: |
B21D 19/04 20060101
B21D019/04; B21D 19/08 20060101 B21D019/08 |
Claims
1. A tool for roll forming an end portion of a conduit to form a
seat for a ferrule on the outer surface of the conduit, the tool
comprising: a frame; a forming roller mounted on the frame for
rotation about an axis; a support on the frame facing the forming
roller supporting the conduit for rotation about an axis parallel
to the axis of the forming roller; a mechanism for moving the
forming roller and support toward each other so that they may
engage the surface of the conduit; the forming roller being
cylindrical and having a cylindrical surface to engage the surface
of the conduit to smooth the outer surface of the conduit when the
tool is rotated relative to the conduit and the mechanism moves the
forming roller and the support so they engaged surface of the
conduit; the forming roller further including a first
circumferential ridge rising a first distance above the cylindrical
surface of the forming roller and shaped and contoured to form a
first seat for a first ferrule in the surface of the conduit.
2. The tool of claim 1 including a first circumferential edge
rising a second distance above the cylindrical surface of the
forming roller, the second distance being less than the first
distance, the first edge making a witness line on the surface of
the conduit when the tool is rotated relative to the conduit.
3. The tool claim 2 including a second circumferential edge rising
above the cylindrical surface of the forming roller, the first
circumferential edge being spaced a predetermined distance from the
second circumferential edge the second edge making a witness line
on the surface of the conduit when the tool is rotated relative to
the conduit.
4. The tool of claim 3 in which the first edge and the second edge
extend the same distance above the cylindrical surface of the
forming roller.
5. The tool of claim 1 wherein the forming roller includes a
tapered surface axially spaced from the ridge, the tapered surface
starting from the cylindrical surface and increasing in diameter as
the axial distance from the ridge increases, the tapered surface
forming an inward taper on the outside surface of an end portion of
the conduit as the forming roller engages the surface of the
conduit.
6. The tool of claim 5 including a first circumferential edge
rising a second distance above the cylindrical surface of the
forming roller, the second distance being less than the first
distance, the first edge making a witness line on the surface of
the conduit when the tool is rotated relative to the conduit.
7. The tool claim 6 including a second circumferential edge rising
above the cylindrical surface of the forming roller, the first
circumferential edge being spaced a predetermined distance from the
second circumferential edge the second edge making a witness line
on the surface of the conduit when the tool is rotated relative to
the conduit.
8. The tool of claim 7 in which the first edge and the second edge
extend the same distance above the cylindrical surface of the
forming roller.
9. The tool of claim 8 wherein the distance between the first and
second edges corresponds to a desired travel of a nut driving a
ferrule into sealing engagement with the conduit.
10. The tool of claim 8 where in the distance above the cylindrical
surface of the first and second edges is selected so that the first
and second edges do not engage the surface of the conduit until the
seat has been formed to the desired depth.
11. The tool of claim 1 including a first stop surface fixed with
respect to the frame and positioned to limit movement of the
conduit in one axial direction when the tool is rotated relative to
the conduit.
12. The tool of claim 11 including a second stop surface spaced
from the first stop surface and fixed with respect to the frame,
the second stop surface being position to limit axial movement of
the conduit in a second axial direction opposite the first axial
direction.
13. The tool of claim 12 wherein the first and second stop services
are positioned to cooperate with the groove in the mandrel.
14. The tool of claim 11 further including a mandrel, the mandrel
locking to an inside surface of the conduit and having a group
positioned a predetermined distance from an end face of the conduit
when the mandrel is locked to the conduit.
15. The tool of claim 14 wherein the mandrel includes at least one
radially expandable member for locking the mandrel to the
conduit.
16. The tool of claim 14 wherein the mandrel includes a positioning
face to locate the mandrel with respect to an end face of the
conduit.
17. The tool of claim 1 including a second circumferential ridge
rising above the cylindrical surface of the forming roller, the
second circumferential ridge being shaped and contoured to form a
second seat for a second ferrule.
18. The tool of claim 17 including first and second circumferential
edges rising a second distance above the cylindrical surface of the
forming roller, the first and second circumferential edges forming
a pair of parallel circumferential witness lines on the surface of
the conduit when the tool is rotated relative to the conduit.
19. The tool of claim 18 including a tapered surface rising from
the cylindrical surface and shaped to form an inward taper on an
end portion of the conduit when the tool is rotated relative to the
conduit.
20. The tool of claim 19 further including a mandrel proportioned
to engage the interior of the conduit and having a pair of parallel
positioning faces, the tool having first and second stop surfaces,
each positioned to engage one of the positioning faces to limit
axial movement of the conduit when the tool is rotated relative to
the conduit.
Description
TECHNICAL FIELD
[0001] The present disclosure relates to compression fittings for
relatively large diameter conduits.
BACKGROUND
[0002] This disclosure teaches how to secure a fitting to a
relatively large diameter, thick-walled metal conduit. Thick-walled
conduits that are 1 inch in diameter may have a wall thickness of
about 0.120 inches. Thick-walled conduits that are three quarters
of an inch in diameter may have wall thickness of about 0.109
inches. Thick-walled conduits that are 1/2 inch in diameter may
have wall thickness of about 0.083 inches. Conventional compression
fittings may not work well for such conduits when the conduits are
made of particularly hard materials or when the operating pressures
are particularly high.
[0003] Conventional compression fittings rely to some extent on the
ability of one or more ferrules to bite into the tube wall as the
fitting is tightened in place. At the same time the ferrule(s) may
smooth irregularities in the surface of the conduit, irregularities
such as scratches from manufacturing or rough handling. When the
conduit is made of a hard material or the walls are relatively
thick, the ferrule may not be able to perform the required
functions effectively. One solution has been to machine a groove in
the conduit into which the ferrule(s) may be driven to effect the
seal. Another solution has been to roll form a groove into the
conduit. See, e.g., U.S. Pat. No. 5,907,966. Both techniques have
drawbacks in that they may not reproducibly form a groove of
uniform depth. Machining may be difficult outside of a factory
setting. Both roll forming and machining may result in fittings
that do not seal properly against the conduit.
SUMMARY
[0004] According to this disclosure, the problem is solved by
rolling the end of a metal conduit both to form one or more seats
into which a ferrule can bite and to smooth the outside surface of
the conduit. In addition to assist proper assembly of the fitting
into the conduit, the leading end portion of the conduit can be
tapered inward to make it easier to install, and witness lines can
be formed in the conduit. Witness lines serve to signal that the
seat is formed to the proper depth, and also to assure the leading
end portion of the conduit is inserted fully into the fitting when
the fitting is finger tight and that the fitting is thereafter
properly made up.
[0005] A tool for rolling the conduit end portion has a C-shaped
body, smooth rollers to support the conduit on one arm of the C and
a contoured forming roller mounted to be tightened against the
conduit opposite the smooth rollers. The contoured roller has at
least one ridge which forms a seat in the conduit shaped,
proportioned and positioned to engage a ferrule as the fitting is
tightened on the conduit. The contoured roller may also include a
tapered surface that bears against an end portion of the conduit to
form a taper, and raised edges to form witness lines to confirm
that the seat has been formed to the proper depth and that the
fitting has been correctly installed. The smooth rollers and the
contoured roller also smooth the outer surface of the conduit to
help assure a leak-tight seal. The tool may have stop for
positioning the conduit axially. The stop may limit axial movement
of the conduit in one or both axial directions.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] While the specification concludes with claims particularly
pointing out and distinctly claiming the present invention, it is
believed that the same will be better understood from the following
description taken in conjunction with the accompanying drawings in
which:
[0007] FIG. 1 is a plan view of a tool used to roll form an end
portion of a thick-walled conduit and having a forming roller and
two opposing supporting rollers;
[0008] FIG. 2 is a side elevation view of the tool of FIG. 1.
[0009] FIG. 3 is a side elevation view, partly in section, of the
tool of FIGS. 1 and 2 showing a forming roller and two supporting
rollers.
[0010] FIG. 4 is a side elevation view of the forming roller of
FIG. 3, and an end portion of a conduit after a rolling operation
has been completed.
[0011] FIG. 5 is an enlarged view of a portion of FIG. 4 showing
the seat created by the forming roller.
[0012] FIG. 6 is a cross-section view of the rolled conduit of FIG.
3 fully inserted into a fitting, with the fitting shown finger
tight, to nearly expose a rear witness line.
[0013] FIG. 7 is a view similar to FIG. 6 but showing the fitting
after it has been made up by tightening it's nut sufficiently to
expose a forward witness line.
[0014] FIG. 8 is a plan view of a second tool used to roll form an
end portion of a thick-walled conduit and including a tube stop
locator and mandrel that cooperate to hold the conduit against
axial movement in both axial directions during roll forming.
[0015] FIG. 9 is a perspective illustration of a portion of the
tool of FIG. 8.
[0016] FIG. 10 is a perspective illustration of a mandrel that may
be used with the tool of FIG. 8.
[0017] FIG. 11 is a side elevation view of the mandrel of FIG.
10.
[0018] FIG. 12 is a section view of a portion of the forming roller
of FIG. 9.
DETAILED DESCRIPTION
[0019] Tool 10 (FIGS. 1 and 2) is used to roll form an end portion
12 (FIG. 4) of a thick walled conduit 14. The tool 10 includes a
frame 16. The frame 16 is C-shaped, and at one leg 18 of the C
carries a support 20. The support 20 may be a pair of cylindrical
rollers 22 that are mounted in bearings so that they rotate freely.
The rollers 22 have smooth outside surfaces.
[0020] Tool 10 also includes a forming roller 26 described in
detail below. The forming roller 26 is carried by a transport
mechanism 32 for moving it toward and away from the support 20 so
as to engage the outside surface of a conduit 14 as described
below. The transport mechanism 32 can include the second leg 34 of
the C-shaped frame 16. The leg 34 includes a threaded passage 36
(FIG. 3). The transport mechanism 32 also includes a threaded shaft
38 that fits in the passage 36 and a carrier 40.
[0021] The forming roller 26 is rotatably mounted to the carrier 40
and the threaded shaft has one end 50 received in a bore 52 in the
carrier 40. When the shaft 38 is rotated, it advances or withdraws
the carrier 40 toward or away from the leg 18 of the frame 16,
depending upon the direction of rotation. As an alternative to the
manually turned threaded shaft 38, the shaft 38 may be connected to
a motor to effect its rotation, or it may be replaced by a
hydraulic cylinder.
[0022] The frame 16 also includes a stop surface 56. Stop surface
56 serves to position the leading end 102 (FIG. 4) of the conduit
14 (FIGS. 4 and 5) with respect to the forming roller 26.
[0023] The forming roller 26 is shown in FIG. 4 abutting a thick
walled conduit 14 after the roll forming operation has been
performed. The forming roller 26 has a cylindrical surface 70, and
it is rotatably mounted in the carrier 40 for rotation parallel to
the axes of rotation of the rollers 22 (shown in FIG. 2). A first
circumferential ridge 72 (FIG. 4) rises from the cylindrical
surface 70. When the tool 10 has been used to roll form the conduit
14, the ridge 72 forms a seat 74 in the end portion 12 of the
conduit 14. The ridge 72 rises a first distance above the
cylindrical surface 70 so as to form the seat 74 of a predetermined
depth.
[0024] The seat 74 is shaped and proportioned to receive a ferrule
80 (FIGS. 6 and 7) when a compression fitting 82 is connected to
the conduit 14. To this end the seat 74 (FIG. 5) may have wall 84
that is approximately 7.degree. from perpendicular to the outside
surface of the conduit 14, and a wall 86 that is approximately
7.degree. from parallel to the outside surface of the conduit 14.
Both angles may be varied between 1.degree. and 15.degree.. The
seat 74 may be approximately 0.005 to 0.010 inches deep, depending
upon the nature of the materials of which the ferrule 80 and
conduit 14 are made.
[0025] The forming roller 26 (FIG. 4) also includes a first edge 90
and a second edge 92 that rise above the surface 70 of the forming
roller. The edges 90 and 92 serve to form witness lines 94 and 96
on the conduit 14. The first and second edges 90 and 92 rise a
second distance, less than the height of the ridge 72. The edges 90
and 92 normally extend only 0.001 to 0.003 inches above the
cylindrical surface 70 of the forming roller 26. The edges 90 and
92 may be continuous walls perpendicular to the surface of the
forming roller 26, or nearly so. Alternatively, the edges 90 and 92
may be defined by a series of small projections of the same height
as the edges they define.
[0026] When the tool 10 has been used to roll form the end portion
12 of the conduit 14, the first and second edges 90 and 92 form
witness lines 94 and 96, respectively. During the rolling process,
the witness lines do not appear until the seat 74 is formed to a
sufficient depth by the ridge 72. This is true because the edges 90
and 92 do not contact the surface of the conduit 14 until after
ridge 72 has penetrated sufficiently to create the seat 74.
[0027] The forming roller 72 also includes a tapering surface 98.
The tapering surface 98 is located at one end of the forming roller
26, on the opposite side of the ridge 72 from the edges 90 and 92.
When the forming roller 26 is mounted on the carrier 40, the
tapering surface is immediately adjacent the stop surface 56. The
tapering surface 94 serves to bevel the leading end portion 100 of
the conduit 14. A bevel on the leading end portion 100 of the
conduit 14 helps to assure that the conduit 14 will seat fully and
squarely within the fitting 82 (FIGS. 6 and 7).
[0028] To make the tapered leading end 102, the seat 74, and the
witness lines 94 and 96 (FIG. 4) the end portion 12 of the conduit
14 is placed in the tool 10 with its leading end face 102 abutting
the stop surface 56 (FIGS. 1 and 2). The shaft 38 is turned by
means of knob 104 until the forming roller 26 engages the outside
surface of the conduit 14. The tool 10 is then rotated about the
conduit 14, and the carrier 40 is advanced by turning the knob 104.
Rotation of the tool 10 about the conduit 14 with incremental
advances of the carrier 40 continues until the witness lines 94 and
96 appear. When the witness lines 94 and 96 appear, the seat 74 is
a proper depth, and the tool 10 may be removed.
[0029] FIG. 6 shows the conduit 14 inserted into a conventional
fitting 82 with the nut 106 of the fitting finger tight. Before the
leading end face 102 has seated in the fitting 82, both witness
lines 94 and 96 are visible. As the leading end face 102 approaches
bottoming out in the fitting 82, first the leading witness line 96
disappears from view inside the nut 106. When the end face 102 of
the conduit 14 is fully inserted into the fitting, the first
witness line 94 (formed by the first edge 90 of the forming roller
26 (shown in FIG. 4) is just barely visible or will have just
disappeared from view inside the nut 106. If the conduit 14 is not
inserted fully into the compression fitting 82, more than just the
edge of witness line 94 will be visible. Once the conduit 14 is
properly, i.e., fully, inserted in the fitting 82, the nut 106 is
turned 11/4 turns to drive the ferrule 80 into the seat 74. The
spacing between the witness lines 94 and 96 is such that the second
witness line 96 becomes just visible when the nut 106 has been
turned 11/4 turns, as shown in FIG. 7. The spacing between the two
witness lines 94 and 96 depends upon the design of the fitting 82
to which the conduit 14 is to be connected. One and one-quarter
turns is a common industry-standard from finger tight to fully made
up, but other designs are possible for which a different spacing
between the witness lines would be required.
[0030] FIG. 8 shows a second tool 108 for roll-forming an end
portion of a conduit 14'. The tool 108 controls the axial position
of the conduit in two directions during the roll forming operation.
The tool 108 includes a mandrel 110 (FIG. 9) and a tube stop
locator 114. The same numerals with a prime (') added are used for
parts of the tool 108 illustrated in FIGS. 8-11 which are similar
to corresponding parts in FIGS. 1-5.
[0031] In the tool 108 (FIG. 9), the forming roller 112 is mounted
to the leg 18' of the C-shaped frame. Supports 20' (only one shown)
are rotatably mounted to a carrier 40'. The carrier 40' can be
advanced and retracted by means of a threaded shaft 38'.
[0032] The tube stop locator 114 is mounted to the leg 18'. The
tube stop locator 114 has parallel faces 116 and 118 (FIGS. 8 and
9). A U-shaped opening 120 extends between the faces 116 and 118
and opens toward the carrier 40'. As discussed below, the faces 116
and 118 of the tube stop locator 114 serve to limit axial movement
of the conduit 14' while the roll forming operation is being
performed.
[0033] The mandrel 112 (FIGS. 10 and 11) grips the interior surface
of the conduit 14' to be roll-formed and engages the faces 116 and
118 (FIG. 9) of the tube stop locator 114 to limit axial movement
of the conduit during role-forming. The mandrel 112 (FIGS. 10 and
11) includes gripping fingers 132 which fit inside the conduit 14'
to be roll formed. A conical wedge 134 moves the fingers 132
radially outward when the bolt 136 is tightened. In use, the
mandrel 130 is inserted into a conduit until, with the fingers 132
inside, the end face 102' (FIG. 9) of the conduit 14' seats flush
against the shoulder 138 (FIG. 11) on the body 140 of the mandrel
112. Next, the bolt 136 is tightened to hold the mandrel 130 firmly
in place, fixed with respect to the conduit 14'.
[0034] The body 140 of the mandrel has an annular groove 142 with
opposing end faces 144 and 146. The end faces 144 and 146 are
spaced apart slightly more than the thickness of the tube stop
locator 114, i.e., the distance between faces 116 and 118 (FIG. 9).
As a result, the annular groove 142 is received in the U-shaped
slot 120 when the conduit 14' is being roll formed. Engagement of
face 144 of the mandrel 130 with the face 118 of the tube stop
locator 114 and face 146 of the mandrel 112 with the face 116 of
the tube stop locator prevents axial movement of the conduit, while
clearance between the faces is sufficient to permit rotation.
[0035] The forming roller 112 shown in FIGS. 9 and 12 is similar to
the roller 26 shown in FIGS. 1-4, and operates it much the same
way. The forming roller 112 includes edges 90' and 92' that form
witness lines. The forming roller 112 also includes a ridge 72'
that forms a seat for the forward ferrule 80 (FIG. 6), and a
tapering surface 98' that forms a bevel on the leading end of a
conduit to be formed. The forming roller 112 also includes a second
ridge 130 (FIGS. 9 and 12) spaced rearward from the ridge 72'. The
second ridge 130 forms a seat to receive the rear ferrule 134 when
the fitting has been secured in place. The seats 74 and 134 are
preferably about 0.005 to 0.010 inches deep. Accordingly, the
ridges 72' and 130 rise about 0.005 to about 0.010 inches above the
cylindrical surface 136 of the forming roller 112.
[0036] Forming two seats for ferrules in a conduit may be
beneficial when the conduit to be formed is made of a material that
is relatively more difficult to shape because of its material
properties (e.g., hardness, toughness etc.), because of the
thickness of the wall of the conduit, or because the application
requires an especially secure connection between the fitting and
the conduit.
[0037] In addition, forming two seats, one for each ferrule,
reduces the torque necessary to make up the fitting. In some cases
the maximum torque required may be reduced by 25%, an advantage for
a worker who may have to make up many fittings in a day. Also,
using a forming roller such as the roller 112 with two ridges 72'
and 130 helps keep the conduit from moving axially as the roll
forming process takes place.
[0038] Variations of the device illustrated may include using a
motor driven machine to operate the tools 10 and/or 110. In such
case the forming roller 26 and supports 22 may be mounted in a
machine for rotation about the conduit while the forming roller is
forced into the surface of the conduit. In addition, the mandrel
112 may have an expandable rubber element in place of the fingers
132. Because the forming roller 112 with two ridges 72' and 100
3010 s to inhibit axial movement of the conduit during forming, it
may be used within axial stop like the stop 56 (FIGS. 1-3) rather
than the mandrel 110 and tube stop locator 114 (FIGS. 8-11).
[0039] While the inventive principles have been illustrated by the
description of various embodiments thereof, and while the
embodiments of been described in considerable detail, it is not
intended to restrict or in any way limit the scope of the appended
claims to such detail. Additional advantages and modifications will
be readily apparent to those skilled in the art. The invention in
its broader aspects is therefore not limited to the specific
details, representative apparatus, methods and examples shown and
described. Accordingly, departures may be made from such details
without departing from the scope or spirit of the general inventive
principles.
* * * * *