U.S. patent application number 13/949541 was filed with the patent office on 2013-11-21 for ladle for molten metal.
This patent application is currently assigned to GM GLOBAL TECHNOLOGY OPERATIONS LLC. The applicant listed for this patent is GM GLOBAL TECHNOLOGY OPERATIONS LLC. Invention is credited to David D. Goettsch, Jason R. Traub.
Application Number | 20130306263 13/949541 |
Document ID | / |
Family ID | 47220733 |
Filed Date | 2013-11-21 |
United States Patent
Application |
20130306263 |
Kind Code |
A1 |
Goettsch; David D. ; et
al. |
November 21, 2013 |
LADLE FOR MOLTEN METAL
Abstract
A ladle for a molten metal includes a main body having a hollow
interior and an opening for receiving the molten metal. The main
body has a sidewall with a nozzle formed therein. The nozzle
defines an axis of rotation for the main body. The nozzle contacts,
seals and is in fluid communication with the mold. The nozzle is
configured to deliver the molten metal to a mold when the main body
is rotated from a first position to a second position.
Inventors: |
Goettsch; David D.; (Shelby
Township, MI) ; Traub; Jason R.; (Sterling Heights,
MI) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
GM GLOBAL TECHNOLOGY OPERATIONS LLC |
Detroit |
MI |
US |
|
|
Assignee: |
GM GLOBAL TECHNOLOGY OPERATIONS
LLC
Detroit
MI
|
Family ID: |
47220733 |
Appl. No.: |
13/949541 |
Filed: |
July 24, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
13156470 |
Jun 9, 2011 |
8522857 |
|
|
13949541 |
|
|
|
|
Current U.S.
Class: |
164/336 ;
222/604 |
Current CPC
Class: |
B22D 17/30 20130101;
B22D 41/04 20130101 |
Class at
Publication: |
164/336 ;
222/604 |
International
Class: |
B22D 41/04 20060101
B22D041/04 |
Claims
1. A ladle for a molten metal, comprising: a main body having a
hollow interior and an opening for receiving the molten metal, the
main body having a first sidewall with a nozzle formed therein, the
nozzle defining an axis of rotation for the main body and
configured to deliver the molten metal when the main body is
rotated from a first position to a second position, the axis of
rotation lying parallel to a direction that the molten metal is
delivered through the nozzle.
2. The ladle of claim 1, wherein the nozzle is cylindrical and
extends outwardly from the first sidewall.
3. The ladle of claim 1, wherein the axis of rotation of the main
body is eccentric.
4. The ladle of claim 3, wherein the nozzle in the first position
is not in fluid communication with the molten metal in the hollow
interior, and the nozzle in the second position is in fluid
communication with the molten metal in the hollow interior.
5. The ladle of claim 1, further comprising a funnel panel disposed
in the hollow interior of the main body and configured to direct
the molten metal toward the nozzle.
6. The ladle of claim 5, wherein the funnel panel is oriented at an
angle relative to the axis of rotation of the main body.
7. The ladle of claim 6, wherein the funnel panel includes a first
end abutting the first sidewall and a second end abutting a second
sidewall formed in the main body opposite the first sidewall, the
first end abutting the first sidewall at the opening of the hollow
interior and the second end abutting the second sidewall within the
hollow interior and spaced apart from the opening.
8. The ladle of claim 1, wherein the main body has a rear wall that
is angled downwardly relative to the axis of rotation when the main
body is rotated to the second position.
9. The ladle of claim 8, wherein the rear wall extends from the
first sidewall to a second sidewall formed in the main body
opposite the first sidewall.
10. The ladle of claim 1, including a pin formed on the main body
to facilitate the rotating of the main body from the first position
to the second position, the pin disposed along the axis of rotation
of the main body.
11. A casting apparatus comprising: a ladle for a molten metal, the
ladle including a main body having a hollow interior and an opening
for receiving the molten metal, the main body having a sidewall
with a nozzle formed therein, the nozzle defining an axis of
rotation for the main body and configured to deliver the molten
metal when the main body is rotated from a first position to a
second position, the axis of rotation lying parallel to a direction
that the molten metal is delivered through the nozzle; and a mold
having an inlet and a cavity formed therein for receiving the
molten metal, the nozzle of the ladle in fluid communication with
the inlet, the ladle rotatable about the axis of rotation to
deliver the molten metal from the nozzle of the ladle into the
cavity of the mold when the ladle is rotated from the first
position to the second position.
12. The casting apparatus of claim 11, further comprising a gasket
disposed between the nozzle and the mold.
13. The casting apparatus of claim 12, wherein the gasket is
affixed to one of the ladle and the mold.
14. The casting apparatus of claim 12, wherein the gasket is formed
from a compliant composite including fibers and graphite.
15. The casting apparatus of claim 11, wherein the nozzle of the
ladle abuts the mold.
16. The casting apparatus of claim 15, wherein the nozzle is
cylindrical, extends outwardly from the sidewall, and is rotatably
received by the inlet.
17. The casting apparatus of claim 15, wherein the nozzle is a
female feature, the inlet is a male feature, and the nozzle
rotatably receives the inlet.
18. The casting apparatus of claim 11, further including an
actuator or robot to rotate or transport the ladle during each of a
filling operation of the ladle and a pouring operation of the
ladle.
19. The casting apparatus of claim 11, wherein the nozzle is
oriented at an angle relative to a floor surface during delivery of
the molten metal from the ladle to facilitate delivery of the
molten metal from the ladle.
20. The casting apparatus of claim 11, wherein a facing surface of
the mold including the inlet is oriented at an angle relative to
vertical to facilitate delivery of the molten material from the
ladle to the cavity of the mold.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application is a divisional of U.S. patent application
Ser. No. 13/156,470, filed on Jun. 9, 2011, the entire disclosure
of which is incorporated herein by reference.
FIELD OF THE INVENTION
[0002] This invention relates to a ladle and system for the
transfer of a molten metal from the ladle to a casting mold.
BACKGROUND OF THE INVENTION
[0003] The pouring of a molten material, such as metal, for
example, into a casting mold is a significant process variable that
influences the internal soundness, surface conditions, and
mechanical properties, such as tensile strength, porosity, percent
elongation and hardness, of a cast object. Many different designs
for dipping/pouring ladles exist and are used in the foundry
industry. The designs are normally chosen based upon the type of
molten metal and casting mold used. Commonly used ladles make use
of a slot, a lip and a baffle, or a dam at the top of the ladle to
reduce inclusion of furnace metal oxides during metal filling, or
the ladle may incorporate a stopper rod to control the flow of
metal into and out of the ladle.
[0004] Molten metals such as aluminum, for example, react with the
air and create oxides, commonly known as dross, which upon mixing
with the rest of the molten metal creates inclusions and highly
porous regions in the cast object during solidification of the
metal. While many factors influence and account for undesirable
properties in the cast object, two common sources of inclusions
include formation of a dross layer on top of the molten metal, and
the folding action of the molten metal caused by turbulent flow of
the molten metal during pouring. Turbulent metal flow exposes the
molten metal surface area to the air which creates the dross layer.
Depending on the velocity of the molten metal, dictated by the
pouring ladle and basin design and use, the molten metal may
fold-over itself many times, thereby trapping oxygen and metal
oxide layers therein and exposing additional surface area of the
metal to the air.
[0005] Typical foundry ladles are referred to as tilt-pour ladles.
These ladles are substantially cylindrical in shape with an
external spout extending outwardly from the top thereof. Certain
tilt-pour ladles have incorporated a wall or a baffle to separate
the bowl or cavity area of the ladle from the spout. The wall or
baffle may extend to the bottom of the ladle. When the molten metal
is poured, the baffle restricts the flow of molten metal from the
top of the ladle to facilitate the pouring of the metal that is
near the bottom of the ladle. The metal at the bottom of the ladle
is substantially free from dross and other foreign material that
may be present, such as eroded refractory lining and ash created
during a melting process of the metal.
[0006] Although the baffle serves to minimize dross inclusion, the
external spout design still increases the velocity of the material
upon pouring, and may create turbulent flow. The molten metal is
typically transferred from the ladle to a casting mold through the
pour basin. Turbulence of the molten metal also results when the
molten metal is poured through the air and into a pour basin. In
traditional pour basin designs, molten metal flows down the basin
to a mold sprue. The flow of the molten metal through the sprue may
also cause turbulence therein, thereby creating additional
dross.
[0007] There is a continuing need for a ladle and system for
transferring a molten metal from the ladle to a casting mold to
minimize turbulence in the molten metal and militate against
inclusions in a cast object including sub-surface porosity formed
by a tilt-pour molding process.
SUMMARY OF THE INVENTION
[0008] In concordance with the instant disclosure, a ladle and
system for transferring a molten metal from the ladle to a casting
mold to minimize turbulence in the molten metal and militate
against inclusions including sub-surface porosity formed in a cast
object formed by a tilt-pour molding process, has surprisingly been
discovered.
[0009] In a particular embodiment, the ladle is a capped,
horizontal cylinder with a top open face. The open face is used for
filling from a dip well, as well as for metal flash removal. An
off-center cylindrical nozzle is separate from the open face of the
ladle. The nozzle defines an axis of ladle rotation. After ladle
dip and sealing with the horizontal mold wall, the ladle is rotated
to bring molten metal past a height of the nozzle. A funnel panel
is used to direct a volume of the molten metal to the nozzle. The
ladle eliminates a nozzle-to-basin metal drop associated with
traditional tilt-pour ladles while maintaining an efficiency of
being filled from a dip well. This is accomplished by a sealing of
the ladle nozzle to a sprue mold wall. After the nozzle is sealed
to the mold wall, the ladle is rotated to bring molten metal above
the nozzle. At this point, the ladle functions as a filled basin.
The ladle allows easy removal of remnant metal skin. It is also a
direct substitute for traditional semi-permanent mold cylinder head
ladles.
[0010] In one embodiment, a ladle for molten metal includes a main
body having a hollow interior and an opening for receiving the
molten metal. The main body has a sidewall with a nozzle formed
therein. The nozzle defines an axis of rotation for the main body.
The nozzle is configured to deliver the molten metal to a mold when
the main body is rotated from a first position to a second
position.
[0011] In another embodiment, a casting apparatus includes a ladle
for molten metal. The ladle has a main body with a hollow interior
and an opening for receiving the molten metal. The main body has a
sidewall with a nozzle formed therein. The nozzle defines an axis
of rotation for the main body and is configured to deliver the
molten metal when the main body is rotated from a first position to
a second position. The casting apparatus also includes a mold. The
mold has an inlet and a cavity formed therein for receiving the
molten metal. The nozzle of the ladle is in fluid communication
with the inlet. The ladle is rotatable about the axis of rotation
to deliver the molten metal from the nozzle of the ladle into the
cavity of the mold when the ladle is rotated from the first
position to the second position.
[0012] In a further embodiment, a method for transferring molten
metal to a mold includes the steps of filling the ladle with the
molten metal; placing the nozzle of the ladle in fluid
communication with the inlet of the mold; and rotating the ladle
from the first position to the second position to deliver the
molten metal from the ladle into the cavity of the mold.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The above, as well as other advantages of the present
invention, will become readily apparent to those skilled in the art
from the following detailed description of a preferred embodiment
when considered in the light of the accompanying drawings in
which:
[0014] FIG. 1 is a perspective view of a ladle according to one
embodiment of the present disclosure;
[0015] FIGS. 2A-2B are cross-sectional side elevational views of
the ladle shown in FIG. 1, illustrating a filling of the ladle in a
dip well;
[0016] FIGS. 3A-3B are perspective views of the ladle shown in FIG.
1, the ladle cooperating with a fragmentary mold shown in
cross-section to illustrate a filling of the mold;
[0017] FIG. 4 is a cross-sectional fragmentary side elevational
view of the ladle and mold taken along section line 4-4 in FIG. 3A,
and further illustrating a gasket between a nozzle of the ladle and
the mold to seal the nozzle to the mold according to an embodiment
of the disclosure;
[0018] FIG. 5 is a cross-sectional fragmentary side elevational
view of the ladle and mold shown in FIGS. 3A-3B, and further
illustrating a cooperation of a nozzle of the ladle and the mold to
seal the nozzle to the mold according to another embodiment of the
disclosure;
[0019] FIG. 6 is a side elevational view of the ladle shown in FIG.
1, the ladle cooperating with a mold according to a further
embodiment of the disclosure; and
[0020] FIGS. 7A-7B are perspective views of a ladle according to an
alternative embodiment of the present disclosure.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0021] The following detailed description and appended drawings
describe and illustrate various exemplary embodiments of the
invention. The description and drawings serve to enable one skilled
in the art to make and use the invention, and are not intended to
limit the scope of the invention in any manner. In respect of the
methods disclosed, the steps presented are exemplary in nature, and
thus, the order of the steps is not necessary or critical.
[0022] FIG. 1 shows a ladle 100 for molten metal 101 (shown in
FIGS. 2A-3B) according to one embodiment of the disclosure. The
ladle 100 includes a main body 102 having a hollow interior 104 and
an opening 106 for receiving the molten metal 101. The opening 106
has a size that accommodates a dipping operation while permitting
the ladle 100 to hold a sufficient quantity of the molten metal 101
in the hollow interior 104 during transport. For example, the
opening 106 may be a substantially open top used for filling the
hollow interior 104 with the molten metal 101. As a nonlimiting
example, the main body 102 may be in the form of a partial cylinder
with capped ends. Other shapes for the main body may also be used,
as desired.
[0023] The main body 102 has a sidewall 108 with a nozzle 110
formed therein. The nozzle 110 may be integral with the sidewall
108 the main body 102, for example. The nozzle 110 is adapted to
rotate together with the main body 102, for example, up to 360
degrees. The nozzle 110 defines an axis of rotation A for the main
body 102. The axis of rotation A may substantially parallel with a
longitudinal axis of the main body 102, for example. The nozzle 110
is configured to deliver the molten metal 101 when the main body
102 is rotated from a first position (shown in FIG. 3A) to a second
position (shown in FIG. 3B).
[0024] In particular embodiments, the nozzle 110 is cylindrical and
extends outwardly from the sidewall 108. In other embodiments, the
nozzle 110 may be a hole formed in the sidewall 108. Other suitable
shapes and configurations of the nozzle 110 are also within the
scope of the present disclosure.
[0025] It should be understood that the axis of rotation A of the
main body 102 is eccentric, that is, the nozzle 110 is offset from
a center of the sidewall 108. The eccentric axis of rotation A
permits the molten metal 101 in the hollow interior 104 to not be
in fluid communication with the nozzle 110 when the main body 102
is in the first position. The eccentric axis of rotation A also
permits the molten metal 101 of the hollow interior 104 to be in
fluid communication with the nozzle 110 when the main body 102 is
in the second position. The molten metal 101 is thereby delivered
through the nozzle 110 of the main body 102 when the ladle 100 is
rotated from the first position to the second position, in
operation.
[0026] In a further embodiment, the ladle 100 may include a funnel
panel 112. The funnel panel 112 is disposed in the hollow interior
104 of the main body 102. The funnel panel 112 directs the molten
metal 101 toward the nozzle 110 when the ladle 100 is rotated to
the second position during an operation of the ladle 100. For
example, the funnel panel 112 may be oriented at an angle relative
to the axis of rotation A of the main body 102. The funnel panel
112 speeds the delivery of the molten metal 101, for example, by
allowing in combination with the nozzle 110 at least two inches of
head pressure at the nozzle 110. Suitable angles for the funnel
panel 112 may be selected by the skilled artisan, as desired.
[0027] Referring now to FIGS. 7A and 7B, a ladle 100 according to
an alternative embodiment of the disclosure is shown. The main body
102 of the ladle 100 may include the funnel panel 112 as a rear
wall 114 of the main body 102 adjacent the nozzle 110. An
orientation of the rear wall 114 may be such as the rear wall 114
is angled downwardly when the main body 102 is rotated to the
second position. For example, the axis of rotation A defined by the
nozzle 110, and with which the rear wall 114 may be oriented in
parallel, may be offset from a longitudinal axis of the main body
102. The offset allows a side of the main body 102 opposite the
nozzle 110 to lift up and angle a flow of the molten metal 101 to
the nozzle 110 when the main body 102 is in the second position. As
a nonlimiting example, the offset between the axis of rotation A
and the longitudinal axis of the main body 102 may be about ten
degrees (10.degree.). Other suitable offsets may also be used, as
desired. Like the funnel panel 112 described hereinabove, the
angled rear wall 114 may thereby direct the molten metal 101 toward
the nozzle 110 when the ladle 100 is rotated to the second
position.
[0028] With renewed reference to FIG. 1, the ladle 100 of the
present disclosure may be operated by equipment such as an actuator
or robot (not shown). The equipment may rotate or otherwise pivot
the main body 102 of the ladle 100 in each of a filling operation
and a pouring operation. As a nonlimiting example, the ladle 100
may include a pin 116 formed on the main body 102 to facilitate the
rotating of the main body 102 from the first position to the second
position. The pin 116 may be disposed along the axis of rotation A
of the main body 102, for example. In another embodiment, the
equipment may be connected to the main body 102 with a bracket (not
shown) or the like, to permit the transportation and rotation of
the ladle 100. Other means for operating the ladle 100 between the
first position and the second position may also be employed within
the scope of the present disclosure.
[0029] A filling operation with the ladle 100 is shown in FIGS.
2A-2B. The ladle 100 may be filled through use of a dip well 118 or
the like. The ladle 100 may be inserted into the molten material
101 in the dip well 118 in a third position, as shown in FIG. 2A,
for example. The nozzle 110 is not inserted under the molten
material 101 when the ladle 100 is in the third position. As shown
in FIG. 2B, the ladle 100 may then be rotated about the axis of
rotation A to the first position. The nozzle 110 is also not
inserted under the molten material 101 when the ladle 100 is in the
first position. The ladle 100 is thereby filled for transport and a
subsequent casting operation. One of ordinary skill in the art may
select other suitable means for filling the ladle 100, as
desired.
[0030] Referring now to FIGS. 3A-3B, a casting apparatus 120 of the
present disclosure is shown. The casting apparatus 120 includes the
ladle 100 placed in sealing contact with a casting mold 122. The
mold 122 is stationary, in contrast to the ladle 100 that is
movable from the dip well 118 to the mold 122. The mold 122 may be
a semi-permanent type mold, although other types of casting molds
may also be used within the scope of the present disclosure.
[0031] The casting mold 122 has an inlet 124 and a cavity 126
formed therein for receiving the molten metal 101. The inlet 124 is
in fluid communication with the cavity 126 via a mold sprue 128,
for example. The inlet 124 may be an open end of the mold sprue
128. The nozzle 110 of the ladle 100 is in fluid communication with
the inlet 124 of the casting mold 122. The ladle 100 is rotatable
about the axis of rotation A to deliver the molten metal 101 from
the nozzle 110 of the ladle 100 into the cavity 126 of the mold 122
when the ladle 100 is rotated from the first position (shown in
FIG. 3A) to the second position (shown in FIG. 3B).
[0032] In certain embodiments, such as shown in FIGS. 3A-3B and 4,
the casting apparatus 120 may include a gasket 130 disposed between
the nozzle 110 and the mold 122. The gasket 130 facilitates a flat
seal at an interface between the nozzle 110 and the mold 122. The
gasket 130 also permits the ladle 100 to rotate about the axis of
rotation A while maintaining the seal between the nozzle 110 and
the mold 122. The gasket 130 may be formed from a compliant
composite including fibers and graphite, for example. Other
suitable temperature-stable materials may also be employed, as
desired.
[0033] In other embodiments, such as shown in FIG. 5, the nozzle
110 of the ladle 100 sealingly abuts the mold 122. As a nonlimiting
example, the nozzle 110 may be substantially cylindrical and extend
outwardly from the sidewall 108. The nozzle 110 may further be
rotatably received by the inlet 124 of the mold 122. As shown in
FIG. 5, the nozzle 110 may represent a male feature and the inlet
124 may represent a female feature for cooperation with the male
feature. It should be understood that the nozzle 110 may
alternatively be provided as a female feature with the inlet 124
provided as a male feature for cooperation with the female feature,
within the scope of the present disclosure.
[0034] The present disclosure further includes a method for
transferring the molten metal 101 to the casting mold 122. The
method includes providing the ladle 100 and the mold 122 as
described hereinabove and shown in the drawings. The ladle 100 is
first filled with the molten metal 101, for example, as shown in
FIGS. 2A-2B. The nozzle 110 of the ladle 100 is then placed in
fluid communication with the inlet 124 of the mold 122. Prior to
placing the ladle 100 in fluid communication with the inlet 124 of
the mold 122, the ladle 100 is rotated to the first position. The
ladle 100 may be rotated to the first position as part of the
filling operation shown in FIGS. 2A-2B, for example. After the
ladle 100 is placed in fluid communication with the inlet 124 of
the mold 122, the ladle 100 is rotated or otherwise pivoted from
the first position to the second position. The rotation from the
first position to the second position raises the main body 102 of
the ladle above the nozzle 110 and causes the molten metal 101 to
flow out of the ladle 100 through the nozzle 110. The molten metal
101 is thereby delivered from the ladle 100, through the nozzle
110, to the cavity 126 of the mold 122.
[0035] Where the gasket 130 is employed in the casting apparatus
120, for example, as shown in FIG. 4, the step of placing the
nozzle 110 of the ladle 100 in fluid communication with the inlet
124 of the mold 122 may first include a step of aligning the nozzle
110 with the inlet 124 to seal the nozzle 110 to the mold 122. The
gasket 130 may then be disposed between the nozzle 110 and the mold
122 to create the flat seal between the ladle 100 and the mold 122.
In particular embodiments, the gasket 130 may be affixed to one of
the ladle 100 and the mold 122 prior to aligning and placing the
ladle 100 in sealing contact with the mold 122.
[0036] Where male and female cooperation is employed in the casting
apparatus 120, for example, as shown in FIG. 5, the step of placing
the ladle 100 in fluid communication with the inlet 124 of the mold
122 may include a step of inserting the nozzle 110 into the inlet
124 of the mold 122 to seal the nozzle 110 to the mold 122. It
should be appreciated that the ladle 100 remains rotatable about
the axis of rotation A when the nozzle 110 is inserted into the
inlet 124 of the mold 122.
[0037] Referring now to FIG. 6, one of ordinary skill in the art
should appreciate that the ladle 100 may be tilted at an angle
relative to a floor surface. The tilting of the ladle 100
facilitates delivery and removal of the molten metal 101 from the
ladle 100. Where the ladle 100 is tilted at the angle relative to
the floor surface, a facing surface 132 of the mold 122, within
which the inlet 124 of the stationary mold 122 is formed, may also
be angled to permit the sealing of the nozzle 110 with the mold 122
prior to the casting operation. As a nonlimiting example, the
facing surface 132 of the mold 122 may have an angle of
approximately ten degrees (10.degree.) relative to vertical, and
permit the tilting of the nozzle 110 approximately ten degrees
(10.degree.). Other tilt angles and corresponding angles for the
facing surface 132 of the mold 122 may also be used within the
scope of the present disclosure.
[0038] Advantageously, the casting apparatus 120 and method of the
present disclosure delivers superior metal quality than a
conventional tilt-pour process, with an efficiency of a gravity
pour process. The contact between the ladle 100 and the mold 122
specifically minimizes turbulence of the molten metal 101, which
would otherwise be poured through the air with high turbulence into
a pour basin. The casting apparatus 120 and method has also been
shown to minimize initial metal stream surface area and oxide film
formation. Reduced sub-surface porosity and leaker casting scrap is
likewise provided by the casting apparatus 120 and method, due to
the minimization of the turbulence to the molten metal 101 during
the filling of the mold cavity 124. The funnel panel 112 and angled
rear wall 114 of the ladle 100 also contribute to an efficiency of
the ladle 100 by urging the molten metal 101 toward the nozzle 110
for delivery to the mold 122.
[0039] While certain representative embodiments and details have
been shown for purposes of illustrating the invention, it will be
apparent to those skilled in the art that various changes may be
made without departing from the scope of the invention, which is
further described in the following appended claims.
* * * * *