U.S. patent application number 10/398960 was filed with the patent office on 2004-03-11 for method and device for annealing tubes.
Invention is credited to Kuehn, Friedhelm.
Application Number | 20040045646 10/398960 |
Document ID | / |
Family ID | 7660190 |
Filed Date | 2004-03-11 |
United States Patent
Application |
20040045646 |
Kind Code |
A1 |
Kuehn, Friedhelm |
March 11, 2004 |
Method and device for annealing tubes
Abstract
The invention relates to tubes which are coil-shaped, and a
plurality of coils which are annealed together and then coated with
a protective gas. Each coil is connected to an individually
controllable protective gas supply line and to an individual
protective gas exit line. A seal includes a mother plug (1), whose
through-openings (6) are connected to the coils and an adapted
father plug (2), whose through-openings (10) are connected to
separate protective gas lines. A plurality of tube supports (7) are
arranged in a displaceable manner inside the through-openings (6)
of the mother plug (1) and are tightened in a sealed manner inside
the through-openings (10) of the father plug (2) by an actuating
element (9).
Inventors: |
Kuehn, Friedhelm; (Muelheim
a.d. Ruhr, DE) |
Correspondence
Address: |
Fay Sharpe Fagan
Minnich & McKee
Suite 700
1100 Superior Avenue
Cleveland
OH
44114-2518
US
|
Family ID: |
7660190 |
Appl. No.: |
10/398960 |
Filed: |
April 10, 2003 |
PCT Filed: |
October 2, 2001 |
PCT NO: |
PCT/EP01/11363 |
Current U.S.
Class: |
148/687 |
Current CPC
Class: |
C21D 9/54 20130101; C21D
9/08 20130101; C21D 1/74 20130101 |
Class at
Publication: |
148/687 |
International
Class: |
C22F 001/08 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 18, 2000 |
DE |
10051606.8 |
Claims
1. Method for annealing pipes which have been wound into coils, a
plurality of coils being annealed together and purged during
annealing with protective gas, characterised in that each coil is
connected to a separately controllable protective gas inlet and a
separate protective gas outlet:
2. Device to connect a plurality of coils of wound pipes to a
facility for supplying and/or removing protective gas, with a
female plug (1) assigned to the coils with a plug-in opening (3)
and a plurality of passages (6) which can each be connected to an
appertaining coil, a male plug (2) assigned to the facility for
supplying and/or removing protective gas, said male plug (2)
fitting in the plug-in opening (3) of the female plug (1) and
exhibiting a plurality of passages (10) which can each be connected
to an appertaining separate protective gas line, a plurality of
pipe connection pieces (7) which can each be moved axially in an
appertaining passage of the one plug and can be inserted in an
appertaining passage of the other plug to form a seal, and an
actuating element (9) assigned to the male plug (2) for moving the
pipe connection pieces (7) when the male plug is inserted in the
female plug (1).
3. Device according to claim 2, characterised In that the passages
(10) into which the pipe connection pieces (7) can be Inserted to
form a seal exhibit a conically tapered entry zone against which
the appertaining pipe connection piece (7) can be restrained.
4. Device according to claim 2 or 3 characterised in that the
actuating element (9) exhibits a head (8) with a continuously
tapering circumference which can be moved axially in a recess (14)
of the male plug (2), said recess exhibiting a complementary
continuously tapering circumference, wherein the head (8) exhibits
a plurality of passages (12) to accommodate the pipe connection
pieces (7) and is provided with side openings (16) which lead from
the passages (12) to the appertaining circumferential surface and
which each contain a movable restraining element which protrudes
from the circumferential surface, preferably In the form of a ball
(17).
5. Device according to claim 4, characterised in that the head (8)
of the actuating element (10) exhibits an actuating rod (11) which
Is passed centrally through the male plug (2).
6. Device according to claim 4 or 5, characterised in that the
circumference of the head (8) and the circumference of the recess
(14) are continuously tapered away from the female plug (1).
7. Device according to claim 6, characterised in that the passages
(12) of the head (8) widen conically at their entry ends towards
the female plug (1).
8. Device according to any one of claims 4 through 7, characterised
in that the head (8) of the actuating element (9) and the recess
(14) of the male plug (2) exhibit truncated circumferential
surfaces (13, 15 respectively) and are connected with each other so
they cannot turn.
9. Device according to any one of claims 2 through 8, characterised
In that the plug-in opening (3) of the. female plug (1) exhibits a
circumference continuously widening towards the male plug (2) and
that the male plug (2) is provided with a plug-in end which
exhibits a complementary, continuously widening circumference.
10. Device according to claim 9 characterised in that the plug-in
opening (3) of the female plug (1) and the plug-in end of the male
plug exhibit truncated circumferential surfaces (4, 5 respectively)
and are provided with features for fixing the reciprocal plug-in
orientation.
Description
[0001] The invention relates to a method for annealing pipes which
are wound into coils, a plurality of coils being annealed together
and purged during annealing with protective gas.
[0002] A major application of the present invention is the bright
annealing of copper pipes such as those employed extensively in
refrigeration engineering. They are used for transporting the
refrigerant through the relevant heat exchangers. For this purpose,
it is essential for the pipes to be purged during annealing with
protective gas to remove any deposits from the inside of the pipe,
so-called coating. Only a very small amount of residual coating is
permitted as otherwise the refrigeration processes are greatly
impaired.
[0003] Several coils are arranged in annealing supports stacked one
on top of the other and then annealed together. Once the coils have
been pushed into the furnace, the protective gas source is
connected. It is generally the bottom annealing support which is
connected to a protective gas line, the protective gas then being
distributed to the individual coils from the bottom annealing
support.
[0004] Practice has shown that the individual coils from one and
the same charge exhibit different amounts of residual coating.
[0005] The object of the present invention is therefore to achieve
a uniform purge flow rate of the different coils in the charge.
[0006] This object is achieved by the aforementioned inventive
method, characterised in that each coil is connected to a
separately controllable protective gas inlet and a separate
protective gas outlet.
[0007] The invention is based on the realisation that the different
purge flow rates of the individual coils hitherto determined can
only be due to the fact that the individual coils receive different
amounts of purging gas. As the parallel supply conditions are
uniform and the flow resistances of the individual coils do not
differ substantially from each other, the differences in the amount
of purging gas can only be due to the fact that the unavoidable
losses through leakage are different.
[0008] The invention ensures that each coil is purged separately
and that any differences in losses through leakage can be balanced
out. Furthermore, the contaminant content of the protective gas
leaving the system can be monitored so that it is possible to
supply each individual coil with an appropriately adjusted amount
of protective gas. In addition, it is possible not only to control
the protective gas flow rate but also the purging time and the coil
temperature. It Is also possible to not only take the contaminant
composition, for example carbon content, as a basis for control.
Furthermore, selective adjustment to different admissible amounts
of residual coating is possible within one and the same charge.
[0009] In addition, the Invention has one substantial additional
advantage. According to the prior art, the contaminated protective
gas was fed into the furnace, causing contamination of the furnace
inside chamber and the cold coil surfaces. These disadvantages have
been eliminated as the contaminated protective gas is removed
directly from the coil.
[0010] To perform the inventive method, the coils have to be
connected to the separate protective gas lines, both on the inlet
and outlet sides. To perform this step with a minimum amount of
work, namely in one single action, the invention creates a device
to connect a plurality of coils wound from pipes to a facility for
supplying and/or removing protective gas, with
[0011] a female plug assigned to the coils with a plug-in opening
and a plurality of passages which can each be connected to an
appertaining coil,
[0012] a male plug assigned to the facility for supplying and/or
removing the protective gas, said male plug fitting into the
plug-in opening of the female plug and exhibiting a plurality of
passages which can each be connected to an appertaining separate
protective gas line,
[0013] a plurality of pipe connection pieces which can each be
moved axially in an appertaining passage of the one plug and can be
inserted In an appertaining passage of the other plug to form a
tight seal, and
[0014] an actuating element assigned to the male plug for moving
the pipe connection pieces when the male plug is inserted In the
female plug.
[0015] The female plug is mounted on one of the annealing supports,
generally on the bottom annealing support, and the male plug forms
the real docking station inside the furnace. The male plug and the
actuating element can be controlled from outside once the coils are
located In the docking station.
[0016] Furthermore it is possible to make do with one single pair
of plugs, half of the passages then being used to supply the
protective gas and the other half to remove the protective gas.
However, two pairs of plugs are generally used which are arranged
in any manner to each other and can preferably be operated from one
common actuating station. Once the relevant male plug has been
inserted in the female plug, the relevant actuating element Is put
Into operation to grip the connection pieces and to push them into
the relevant passages to form a seal. The passages are preferably
provided with a conically tapered entry zone against which the
appertaining pipe connection piece can be restrained by the
actuating element.
[0017] A further embodiment of the present invention proposes that
the actuating element exhibits a head with a continuously tapering
circumference which can be moved axially in a recess of the male
plug, said recess exhibiting a complementary continuously tapering
circumference, wherein the head exhibits a plurality of passages to
accommodate the pipe connection pieces and is provided with side
openings which lead from the passages to the appertaining
circumferential surface and which each contain a movable
restraining element which protrudes from the circumferential
surface, preferably In the form of a ball.
[0018] During docking, the male plug Is inserted In the plug-in
opening of the female plug. Then the actuating element is moved in
the direction in which its circumference and that of the recess
taper. The restraining elements then come Into contact with the
circumference of the recess and are moved inwards towards the
passages of the actuating element through which the pipe connection
pieces pass. They grip the pipe connection pieces and push them
into their sealing position, pressing into the pipe connections.
Any differences in the positions of the pipe connection pieces are
automatically compensated for. The actuating element Is kept in its
restraining position during annealing and then pushed in the
opposite direction to loosen the connection.
[0019] The head of the actuating element may be provided with an
actuating rod which is passed centrally through the mal plug and
arranged preferably in the form of a circle around the passages of
the head. The actuating rod is passed through the furnace wall to
form a seal and may be operated via a piston mover arranged outside
the furnace.
[0020] The circumference of the head and that of the recess of the
male plug may be tapered towards the female plug. The pipe
connection pieces are then located in the male plug and are moved
by the actuating element In the same direction in which the male
plug is inserted in the plug-in opening of the female plug. The
kinematics are therefore simple as the male plug does not have to
be held separately when the actuating element is moved. However,
this design is complicated from the manufacturing point of view,
apart from the fact that the pipe connection pieces inside the
furnace are wear parts and have to be replaced
[0021] Under certain circumstances, a design In which the
circumference of the head and that of the recess are continuously
tapered away from the female plug is therefore better. The pipe
connection pieces can be moved in the passages of the female plug
and are pulled by the actuating element Into the passages of the
male plug to form a seal. The pipe connection pieces can therefore
be replaced as soon as the annealing supports have left the
furnace. An appropriate lock preferably ensures that the pipe
connection pieces are not removed with the male plug when the
plug-in connection is loosened.
[0022] When the male plug is inserted into the plug-in opening of
the female plug, the pipe connection pieces enter the passages of
the head of the actuating element. For this purpose, it is
advantageous for the passages of the head to widen conically at
their entry ends towards the female plug, automatic centring
thereby being facilitated.
[0023] Designs in which the head of the actuating element and the
appertaining recess of the male plug exhibit a polygonal
cross-section and taper in the shape of a pyramid are also
conceivable. The advantage of such designs is that the angle of the
actuating element relative to the male plug is automatically fixed.
From a manufacturing point of view, however, it is simpler to have
a design, which is also preferred from this aspect, in which the
head of the actuating element and the recess of the male plug
exhibit truncated circumferential surfaces and are connected with
each other so they cannot turn.
[0024] Furthermore, a further embodiment of the invention proposes
that the plug-in opening of the female plug exhibits a
circumference continuously widening towards the male plug and that
the male plug is provided with a plug-in end which exhibits a
complementary, continuously widening circumference. Here a
polygonal, shaped-shaped configuration is also conceivable which
ensures automatic positioning. However, for manufacturing reasons,
truncated configurations with features to fix the reciprocal
plug-in position are to be preferred.
[0025] The Invention will now be described in greater detail with
the aid of a preferred embodiment of the plug-in connection in
conjunction with the enclosed drawing. The drawing shows in:
[0026] FIG. 1 an axial cross-section through the plug-in
connection
[0027] FIG. 1 show a female plug I for mounting on the bottom
annealing support of a stack of coils and a male plug 2 which is
Inserted into a plug-in opening 3 of the female plug on the docking
station. The plug-in opening 3 exhibits a conical circumferential
surface 4 whilst the male plug 2 is provided on its plug-in end
with a complementary conical circumferential surface 5.
Furthermore, means not shown in the Figure are provided which
permit the insertion of the male plug 2 in the plug-in opening 3 of
the female plug 1 only in one or several predefined angles.
[0028] The female plug 1 exhibits a plurality of passages 6 which
can be connected to the individual coils and in which pipe
connection pieces 7 are arranged so they can be moved. The pipe
connection pieces 7 protrude through a head 8 of an actuating
element 9 and are restrained in the passages 10 of the male plug 2
by said actuating element to form a seal. The entry zones of the
passages 10 are conically widened for this purpose as shown. The
passages 10 can be connected to separate protective gas lines.
[0029] The actuating element 9 exhibits an actuating rod 11 which
is preferably connected in one piece with the head 8 and which is
passed centrally through the male plug 2. The passages 10 of the
male plug 2 are distributed in the form of a circle around the
actuating rod 11 of the actuating element 9.
[0030] The head 8 of the actuating element 9 also exhibits passages
12 through which the pipe connection pieces 7 pass. In order to
facilitate Insertion of the connection of the pipe connection
pieces 7 in the passages 12 of the head 8 to establish the plug-in
connection, the passages 12 are conically widened at their entry
ends, as shown.
[0031] The head 8 of the actuating element 9 exhibits a conical
circumferential surface 13 and engages in a recess 14 of the male
plug 2, the recess 14 being provided with a complementary conical
circumferential surface 15. Side openings 16 of the head 8 lead
from the circumferential surface 13 to the passages 12 and serve to
accommodate balls 17 which have the function of restraining
elements.
[0032] When the male plug 2 is inserted in the plug-in opening 3 of
the female plug 1, the pipe connection pieces 7 arranged in the
female plug 1 enter the passages 12 of the actuating element 9. The
head 8 of the actuating element 9 is located near the bottom of the
plug-in opening 3 of the female plug 1 Then the actuating element 9
Is moved downwards in FIG. 1. The balls 17 then come to rest on the
circumferential surface 15 of the recess 14, press progressively
Into the pipe connection pieces 7 and take said pipe connection
pieces 7 with them until they come to rest on the conical entry
zones of the passages 10 of the male plug 2 to form a seal. The
male plug 2 is secured. Means not shown in the Figure ensure that
the actuating element 9 retains a fixed position relative to the
male plug 2.
[0033] The passages 6 of the female plug 1 and the appertaining
passages 10 of the male plug 2 can be connected to protective gas
supply lines or to protective gas removal lines. Then two such
plug-in connections are required to perform the inventive method.
Alternatively, it is possible to connect half of the passages to
the protective gas supply lines and the other half to the
protective gas removal lines. Then one. single plug-in connection
is sufficient.
[0034] Modifications within the scope of the present invention are
perfectly possible. Above all the orientation of the conical
surfaces 13 and 15 of the head 8 of the actuating element 9 and the
appertaining recess 14 can be reversed. The pipe connection pieces
7 then form one component of the male plug 2 and are pushed Into
the relevant sealing zones of the passages 6 of the female plug
1.
* * * * *