CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to provisional patent application entitled, IN SITU
SLURRY FORMATION AND DELIVERY TO DIE CAST MACHINES, filed
August 23, 2005, having a serial number of 60/710,165, the disclosure of which is hereby incorporated by reference in its entirety.
FIELD OF THE INVENTION
[0002] The present invention relates generally to casting metal alloys. More particularly,
the present invention relates to semi-solid metal casting.
BACKGROUND OF THE INVENTION
[0003] Casting complex geometries may yield products with undesirable shrink porosity, which
can adversely impact the quality and integrity of the cast part. Shrink porosity defines
a condition that arises as a metal part begins to shrink as it cools and solidifies
along the outer surface, leaving pockets of air (referred to as "voids") trapped in
the center of the part. If the voids are not reconstituted with the metal, the cast
part is termed "porous." This condition is prevalent with the use of aluminum alloys
as the casting material.
[0004] Semi-solid metal casting (SSM) may be used to address this problem of porosity in
cast products, particularly for aluminum alloys. Advantages to SSM casting include
producing high quality parts with structural integrity, rigidity, strength and ductility.
[0005] As such, it is desirable to use SSM methods as often as feasible. Therefore, it is
desirable to provide a mechanism to allow die casting machines the ability to use
SSM metals without replacing them or undergoing costly modifications to existing machines.
SUMMARY OF THE INVENTION
[0006] The foregoing needs are met, to a great extent, by the present invention, wherein
in one aspect an apparatus is provided that in some embodiments a mechanism to allow
die casting machines the ability to use SSM metals without replacing them or undergoing
costly modifications to existing machines.
[0007] In accordance with one embodiment of the present invention, an apparatus for converting
molten metal to semi-solid metal includes a conduit having an inlet and an outlet
to transport the molten metal, and a temperature regulator disposed adjacent the conduit
to regulate the temperature of the molten metal, and a housing surrounding the conduit
and the temperature regulator.
[0008] In accordance with another embodiment of the present invention, a method for converting
molten metal to semi-solid metal includes coupling a conduit to a die casting machine,
wherein the conduit comprises an inlet, an outlet and a body disposed between the
inlet and the outlet, regulating the conduit's temperature, surrounding the conduit
with a housing, inserting molten metal at the inlet, cooling the molten metal to semi-solid
metal in the body, and expelling semi-solid metal from the outlet.
[0009] In accordance with yet another embodiment of the present invention, a system for
converting molten metal to semi-solid metal includes means for coupling a conduit
to a die casting machine, wherein the conduit comprises an inlet, an outlet and a
body disposed between the inlet and the outlet, means for regulating the conduit's
temperature, means for surrounding the conduit with a housing, and means for cooling
the molten metal to semi-solid metal in the body.
[0010] There has thus been outlined, rather broadly, certain embodiments of the invention
in order that the detailed description thereof herein may be better understood, and
in order that the present contribution to the art may be better appreciated. There
are, of course, additional embodiments of the invention that will be described below
and which will form the subject matter of the claims appended hereto.
[0011] In this respect, before explaining at least one embodiment of the invention in detail,
it is to be understood that the invention is not limited in its application to the
details of construction and to the arrangements of the components set forth in the
following description or illustrated in the drawings. The invention is capable of
embodiments in addition to those described and of being practiced and carried out
in various ways. Also, it is to be understood that the phraseology and terminology
employed herein, as well as the abstract, are for the purpose of description and should
not be regarded as limiting.
[0012] As such, those skilled in the art will appreciate that the conception upon which
this disclosure is based may readily be utilized as a basis for the designing of other
structures, methods and systems for carrying out the several purposes of the present
invention. It is important, therefore, that the claims be regarded as including such
equivalent constructions insofar as they do not depart from the spirit and scope of
the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is an illustration of an in-situ slurry formation apparatus according to an
embodiment of the present invention.
[0014] FIG. 2 is an illustration of a HPDC die casting machine having the in-situ slurry
formation apparatus incorporated therein.
[0015] FIG. 3 is a detailed representation of the in-situ slurry formation apparatus configured
for the HPDC machine of FIG. 2.
[0016] FIG. 4 is a representation of a HVSC die casting machine having the in-situ slurry
formation apparatus incorporated therein.
[0017] FIG. 5 is a detailed representation of the in-situ slurry formation apparatus configured
for the HVSC machine of FIG. 4.
[0018] FIG. 6 is an illustration of the microstructure obtained for a 356 alloy.
[0019] FIG. 7 is an illustration of the microstructure obtained for a 206 alloy.
DETAILED DESCRIPTION
[0020] The foregoing needs are met, to a great extent, by the present invention, wherein
in one aspect an apparatus is provided that in some embodiments combines various methods
of die casting with semi-solid metal in an efficient manner. There are, of course,
additional embodiments of the invention that will be described below and which will
form the subject matter of the claims appended hereto.
[0021] Casting methods such as die casting, gravity permanent mold casting, and squeeze
casting have been used for Aluminum-Silicon (Al-Si) alloys. In thixocasting semi-solid
metal casting (SSM), specially prepared metal slugs are gradually brought to a semi-solid
state, then transferred to the casting machine, where a ram uses pressure to inject
the SSM into a die. Once solidified, the die opens and the cast part is ejected. With
SSM, the viscosity is fairly high so the injection speed is lower than with conventional
pressure die casting. This results in little or no turbulence, which reduces porosity.
In rheocasting SSM, the SSM slurry is made from the liquid state. In an embodiment
of the present invention, the rheocast SSM process is performed.
[0022] Die casting is a manufacturing process wherein a strong, durable and intricate product
can be mass produced. Die casting is also referred to as high pressure casting and
has the unique ability to transform raw material into a finished form in the shortest
possible cycle time. Often the finished product requires no additional machining or
other operations. Die cast products are also dimensionally stable. Die casting is
an efficient, economical process allowing for a broad range of geometries, high speed
production and closer tolerances that provide heat resistant, stronger products. Thin
wall castings are stronger and lighter than products produced using other casting
methods.
[0023] FIG. 1 is an illustration of an in-situ slurry formation apparatus 10 according to
an embodiment of the present invention. The in-situ slurry formation apparatus 10
is configured with and includes a funnel block 12. The funnel block 12 includes a
funnel 14, heaters 24, coolers 22 and temperature sensors 26. The funnel 14 has generally
a funnel shape with one end having a larger diameter than another end, although any
other type of configuration may be used. The funnel 14 is used to transport and cool
a liquid metal from a liquid metal source to a die casting machine. Liquid metal is
poured into the funnel 14 at an inlet 16 and passes through the funnel 14 through
a metal flow path 18. The metal flow path 18 can be as long or short and have various
turns as required, as long as it allows the liquid metal to cool down to a semi-solid
metal state or as close as desired by a user. As the metal passes through, it cools
to SSM state, or near SSM state, and exits the funnel 14 at an outlet 20.
[0024] The funnel 14 is maintained at a steady state temperature by using both coolers 22
and heaters 24 placed at various locations throughout the funnel block 12. The coolers
22 are pathways in the funnel block 12 whereby a cooling medium is passed. For example,
oil, coolant or water may be used as the cooling medium. Other types may also be used.
The cooling medium may flow through the passages or be contained statically therein.
[0025] The cooling passages may be combined with a water chiller that pumps and cools the
cooling medium. Also, a re-circulatory system can be used to pump water through and
then provide a tower that allows the water to cool. If heaters are selected, they
can be used in conjunction with a cooling medium.
[0026] An alternative system may also be used to maintain the funnel 14 at a steady state
temperature. A hot oil system offers similar capabilities as a water chiller. Also,
an advantage of using hot oil instead of water is that the hot oil may heat the funnel
as well as cool it, eliminating the need for separate heaters. The hot oil may further
maintain a higher set temperature than could be maintained with a water system. The
hot oil system or water cooler/heater system may be used to heat or cool the funnel
as required by the user.
[0027] Heaters 24 may be cartridge heaters or any such heating device as may be appropriate.
Temperature sensors 26 are placed in the funnel block 12 to determine and regulate
the temperature. The temperature sensors 26 may be thermocouples or any such temperature
sensor as may be convenient To keep the temperature at a set range, thermocouples
may be used in the system to monitor the temperatures.
[0028] These temperature sensors 26 send the temperature signal to a controller (not shown).
This controller has a preset temperature range that is the desired temperature range
for the process. If the signal received from the temperature sensors 26 is below the
range, the controller signals to a relay which will allow for power to run through
the heaters 24 and heat the funnel block 12. If the temperature exceeds the range,
the controller can be used to send a signal to the relay that opens and closes a valve,
letting the cooling medium run through the coolers 22. When the temperatures fall
back inside the range, the heating or cooling may be turned off. If the temperature
is in the preset temperature range, no cooling or heating may be necessary. A similar
process, using a controller, would be followed if the hot oil system is used.
[0029] The funnel block 12 and the outlet 20 can be configured to mate with various die
casting machines. Some examples of die casting machines are discussed below, and are
not limited to these machines. The size of the funnel block 12 depends on the amount
of metal to be poured through and the amount of heat to be removed. For example, the
funnel block 12 may be approximately 7.375 inches tall, 10 inches wide and 11.5 inches
in length. The funnel block 12 dimensions may vary as necessary.
[0030] The funnel block 12 may be attached to the die casting machines using mounting brackets
or any such means as is desired and feasible. The funnel block 12 may also be welded
to the die casting machine.
[0031] Aluminum adheres to steel and other metals and has a tendency to oxidize and form
a thin layer of oxidized aluminum upon contacting such metals. The layer of oxidized
aluminum may flake off and enter the metal stream. Other contaminants may also enter
the metal stream. To minimize or eliminate this problem, a non-wetting coating may
be applied to the inside surface area of the funnel 14 to prevent oxide accumulation.
There are several types of coatings that are available, for example, tungsten thermal
coatings, boron nitride coatings and ceramic coatings. These coatings prevent the
aluminum from oxidizing. To further prevent metal contamination, the funnel 14 may
be separated at parting line with the use of automation to allow for blow off. Other
methods of preventing contamination may also be used.
[0032] An embodiment of the presently claimed invention includes the in-situ slurry formation
apparatus 10 mounted to machines without the need to modify the existing machines
or change the layout to accommodate more space than would otherwise be necessary.
These machines also need not be replaced with machines specially designed for SSM.
[0033] High pressure die casting (HPDC) at forces exceeding 4500 pounds per square inch
also allow for liquid metal squeeze casting and SSM die casting. Squeeze casting is
a method by which molten alloy is cast without turbulence and gas entrapment at high
pressure, to yield high quality, dense and treatable components. In contrast, SSM
uses semi solid metal billets cast to provide dense heat treatable castings with low
porosity. Thus, products may be cast using either SSM casting or liquid metal squeeze
casting.
[0034] Die casting produces complex shapes at lower costs. The use of semi-solid metal or
liquid slurry metal as described herein over conventional molten metal reduces fluid
turbulence when injected into the die. In this manner, the amount of air that is sequestered
within the final part is reduced. Less air in the final part lends greater mechanical
integrity and allows cast products to be heat treated. In addition, metals that are
SSM cast require less heat which reduces cost and improves longevity of the molds
and dies.
[0035] The microstructure of SSM cast products can determine the mechanical properties of
the product. As such, the microstructure can be manipulated to achieve desired results.
One way to manipulate the final microstructure of an SSM cast part is to control the
time the metal remains in the SSM range. That is, the amount of time the metal spends
in the shot sleeve before it is injected into the molds can be regulated or optimized
for a desirable microstructure. Alternatively, molten metal at a predetermined temperature
may be poured into the shot sleeve of shuttle presses, i.e. presses that lack an indexing
feature.
[0036] HPDC is a large volume, high productivity process for the production of complex thin
walled castings with part weights ranging from a few grams to more than 15 kg. HPDC
has been known for the production of housings and other automotive front end structures
and instrument panels.
[0037] The horizontal cold chamber die casting machine is the basis of the HPDC technology.
In the cold chamber process, the metal reservoir is separated from the injection system.
The metal is filled into the steel cold chamber which is typically between 200 and
300°C. The typical production cycle in the HPDC consists of leading metal into the
cold chamber, moving the plunger and rapidly filling the die which dissipates the
latent heat. During solidification, the casting is pressurized hydraulically by the
plunger to feed the solidification shrinkage. Locking forces up to 4000 tons are available
to withstand the large pressures. The die is then opened and the cast product is ejected.
[0038] Hydraulic energy is provided by computerized systems that permit control of metal,
position, velocity and plunger acceleration to optimize the flow and the pressure
during filling and solidification. The die cavity may be evacuated to reduce air entrapment
during die filling. Therefore, high integrity die casting can be produced by utilizing
vacuum systems. Alternatively, SSM can be used to reduce turbulence. In conventional
die casting, the expertise of the foundry worker is critical to the final cast product.
Therefore, SSM takes the guess work out of casting and results in a consistently high
quality cast product.
[0039] A short die filling time and thin walls result in high cooling rates. This promotes
a fine grain size which provides decent mechanical properties. The alloy itself is
also very important. The alloy characteristics must fulfill the necessary requirements
of castability which involves higher fluidity, good feeding and low hot tearing technology.
[0040] HPDC also allows for rapid solidification and alloy flexibility in that the machines
can accommodate hypoeutectic or hypereutectic alloys, those containing less than 12.7%
silicon or more than 12.7% silicon, respectively. HPDC also allows for a greater number
of cavities per die.
[0041] FIG. 2 is an illustration of a HPDC die casting machine having the in-situ slurry
formation apparatus 10 incorporated therein. The HPDC casting cycle consists of a
holding furnace 28 that retains the liquid metal to be cast. A ladle (not shown) takes
the metal and pours it into the in-situ slurry formation apparatus 10, where the liquid
metal transforms into the SSM state. The SSM metal then exits the in-situ slurry formation
apparatus 10 into a pour hole 34. A hydraulic system 30 then provides a shot cylinder
32 the ability to inject the SSM metal into a die cavity 36.
[0042] The cold chamber 38 holds the liquid metal in place. The cold chamber 38 in a HPDC
machine is where the metal is poured in by the ladle from the furnace before the metal
is injected into the die. The metal is transferred from the furnace into the in-situ
slurry formation apparatus 10 and then the metal flows into the cold chamber 38. Once
the metal is in the cold chamber, the metal will be injected into the die.
[0043] Die 40 are then moved forward by a platen 42 and the platen 42 is held in place by
tie bars 44 while the metal is cast. The platen 42 reciprocating movement is controlled
by clamping knuckles 46, closing and locking the die 40, maintaining adequate pressure,
permitting the metal to solidify, opening the die 40 and ejecting the cast product.
The product may then be appropriately finished or sprayed.
[0044] FIG. 3 is a detailed representation of the in-situ slurry formation apparatus 10
configured for the HPDC machine 48 of FIG. 2. In particular, the funnel block 12 may
be disposed over an injection sleeve 50. Metal exiting the funnel 14 at the funnel
exit 20 enters the injection sleeve 50 at the injection sleeve inlet 52 and exits
the injection sleeve 50 at the injection sleeve outlet 54. The injection sleeve inlet
52 may be associated with the pour hole 34 of FIG. 2.
[0045] The temperature of the molten metal entering the in-situ slurry formation apparatus
10 should be above the liquidus temperature for the particular aluminum alloy in the
furnace. For certain aluminum alloys, depending on the alloy chemistry, the metal
temperature should be even higher than the liquidus to prevent sludge formation in
the furnace. However, too much superheat (temperatures over the liquidus) allows for
more hydrogen to enter the metal which leads to casting defects. The higher the superheat
of the metal in the furnace, the more temperature the in-situ slurry formation apparatus
10 has to remove to get the metal in the SSM range. The metal temperature in the furnace
needs to be as low as possible but still be above the liquidus temperature. The temperature
must also prevent any sludge particles from forming in the particular alloy. Thus,
the temperatures will vary with the particular alloy chemistry.
[0046] In-situ slurry formation apparatus 10 temperatures should be at a temperature that
can be maintained at a steady state from cycle to cycle. This depends on the size
of in-situ slurry formation apparatus 10 and the amount of metal being poured through
the in-situ slurry formation apparatus 10. This temperature will also be kept as low
as possible. However, the temperature should be high enough so the metal will not
solidify inside the in-situ slurry formation apparatus 10. Therefore, the temperature
range may be in the range of 150 degrees Fahrenheit to 500 degrees Fahrenheit. However,
the ranges may vary based on the in-situ slurry formation apparatus 10 size, metal
chemistry and metal quantity.
[0047] FIG. 4 is a representation of a Horizontal with Vertical Shot Components, (HVSC)
die casting machine 56 having the in-situ slurry formation apparatus 10 incorporated
therein. The liquid metal is contained in a holding furnace 58. A ladle (not shown)
pours the liquid metal from the holding furnace 58 into the in-situ slurry formation
apparatus 10. The liquid metal is transformed into SSM state in the in-situ slurry
formation apparatus 10. Then, a shot cylinder 60 tilts towards the in-situ slurry
formation apparatus 10 and the SSM metal enters the shot cylinder 60.
[0048] The shot cylinder 60 then tilts back to the original vertical position. The tilt-docking
injection unit or shot cylinder 60 contains a separated shot sleeve 64 for cooling
and transfer. A hydraulic system 62 then pushes the shot sleeve 64, enveloped by the
shot cylinder 60, into the die cavity 66, and the shot sleeve 64 deposits the SSM
metal. A platen 72 then moves die 68 and locks the die in place using tie bars 70.
Clamping knuckles 74 allow the die 68 to open and close. Once the SSM metal is cast,
the cast product is ejected when the platen 72 moves back. Thus, HVSC machines contain
horizontal die clamping with a vertical, high pressure delivery system.
[0049] FIG. 5 is a detailed representation of the in-situ slurry formation apparatus 10
configured for the HVSC machine of FIG. 4. HVSC is a horizontal clamping vertical
shot chamber machine. The sleeve is vertical at a 15-20 degree angle and it fills
up the tube at an angle. The liquid metal is transferred and poured into the funnel
14 where the metal flows through the funnel 14 undergoing conduction and heat loss.
The metal exiting the funnel 14 is at SSM state and is then injected into the die,
forming a cast product.
[0050] The in-situ slurry formation apparatus 10 is disposed over the injection sleeve 64.
The SSM metal exits the funnel block 12 at the funnel exit 20, into the injection
sleeve inlet 78 and exits the injection sleeve 64 via the injection sleeve outlet
80. The injection sleeve 64 may be associated with the shot cylinder 60 of FIG. 4.
[0051] Although the in-situ-slurry formation apparatus 10 is shown with HPDC and HVSC machines,
one skilled in the art will recognize that any casting machine in existence now or
created later may easily be incorporated with the in-situ slurry formation apparatus
10, without being outside the scope of this invention.
[0052] FIG. 6 is an illustration of the microstructure obtained for a 356 alloy. FIG. 7
is an illustration of the microstructure obtained for a 206 alloy. A variety of metals
and alloys may be used in the in-situ-slurry formation apparatus 10. However, the
in-situ-slurry formation apparatus 10 may be particularly suitable for 356, 357, 206,
380, 383, 390 alloys, as well as ADC-12 and 7XX series alloys.
[0053] In addition to providing SSM slurry and to achieving the desired microstructure,
the in-situ slurry formation apparatus 10 may also be used with liquid metal squeeze
casting or conventional high pressure die casting. The in-situ slurry formation apparatus
10 removes heat from the liquid metal as the metal flows through. This removal of
heat lowers the temperature of the metal and reduces cycle time. The lower temperature
of the metal permits it to solidify faster and increases the efficiency of the process.
Thus, the in-situ slurry formation apparatus 10 may be used to provide SSM slurry
or lower temperature liquid metal squeeze casting for a variety of applications.
[0054] The present invention, therefore, easily allows existing machinery to accommodate
SSM without the need for costly capital equipment or additional space in the plants.
The in-situ slurry formation apparatus 10 may be formed with a steel insert with copper
and beryllium casings. In addition, it is highly wear resistant. The in-situ slurry
formation apparatus 10 may also be fabricated from ANVILOY®, (Mallory Alloys Group,
St. Albans, England) which is a highly conductive steel.
[0055] ANVILOY® is a tungsten based material made using high temperature powder metallurgy
techniques. It was developed specifically for its high temperature strength and excellent
thermal conductivity. It is used in place of lower conductivity high temperature tool
steels. A benefit of ANVILOY® is its simplicity of tool manufacture i.e., no heat
treatment, low erosion and excellent resistance to thermal cracking. This allows for
ANVILOY® to replace H-13 steel. High thermal conductivity allows increased cooling
rates in difficult to cool areas of a die casting and has the potential to increase
production rates. ANVILOY® can be easily machined and can be repair welded.
[0056] Some of the benefits of ANVILOY® include minimal thermal fatigue, minimal soldering,
low erosion, and accelerated cooling. ANVILOY® may be easily machined and worn parts
are easy to remachine into smaller diameter core pins. ANVILOY® may be easily welded
and repaired and requires no heat treatment before or after machining.
[0057] The many features and advantages of the invention are apparent from the detailed
specification, and thus, it is intended by the appended claims to cover all such features
and advantages of the invention which fall within the true spirit and scope of the
invention. Further, since numerous modifications and variations will readily occur
to those skilled in the art, it is not desired to limit the invention to the exact
construction and operation illustrated and described, and accordingly, all suitable
modifications and equivalents may be resorted to, falling within the scope of the
invention.
1. An apparatus for converting molten metal to semi-solid metal comprising:
a conduit having an inlet and an outlet to transport the molten metal; and
a temperature regulator disposed adjacent the conduit to regulate the temperature
of the molten metal; and
a housing surrounding the conduit and the temperature regulator.
2. The apparatus of claim 1, wherein the temperature regulator further comprises a heater,
a cooler and a temperature sensor, operably coupled to a controller.
3. The apparatus of claim 1, wherein the temperature regulator further comprises a hot
oil system and a temperature sensor operably coupled to a controller.
4. The apparatus of claim 3, wherein the hot oil system is configured to heat and cool
the conduit.
5. The apparatus of claim 1, wherein the conduit has a funnel shape.
6. The apparatus of claim 5, wherein the funnel comprises a first end having a first
diameter, a second end having a second diameter and a path disposed between the first
and second ends, wherein the first diameter is larger than the second diameter, and
wherein the path has a non-linear configuration.
7. The apparatus of claim 1, wherein the conduit has a length configured to cool molten
metal to semi-solid metal.
8. The apparatus of claim 1, wherein the housing is configured to couple to a die casting
machine.
9. The apparatus of claim 1, wherein the conduit further comprises a non-wetting coating
on an inside surface of the conduit.
10. The apparatus of claim 9, wherein the non-wetting coating further comprises a tungsten
thermal coating, a boron nitride coating or a ceramic coating.
11. The apparatus of claim 1, wherein the outlet is coupled to a die casting machine inlet.
12. The apparatus of claim 1, wherein the apparatus is configured to couple to a high
pressure die casting (HPDC) machine.
13. The apparatus of claim 1, wherein the apparatus is configured to couple to a horizontal
with vertical shot components (HVSC) die casting machine.
14. The apparatus of claim 1, wherein the apparatus is configured to convert molten metal
206, 356, 357, 380, 383, 390, ADC-12 and 7XX alloys to semi-solid metal.
15. The apparatus of claim 1, wherein the conduit further comprises a thermally conductive
material.
16. The apparatus of claim 15, wherein the conduit further comprises a steel insert with
copper and beryllium casings.
17. The apparatus of claim 15, wherein the conduit further comprises tungsten.
18. A method for converting molten metal to semi-solid metal comprising:
coupling a conduit to a die casting machine, wherein the conduit comprises an inlet,
an outlet and a body disposed between the inlet and the outlet;
regulating the conduit's temperature;
surrounding the conduit with a housing;
inserting molten metal at the inlet;
cooling the molten metal to semi-solid metal in the body; and
expelling semi-solid metal from the outlet.
19. The method of claim 18, wherein the step of regulating the temperature of the conduit
is done through a heater, a cooler and a temperature sensor operably coupled to a
controller.
20. The method of claim 19, wherein the step of regulating the temperature of the conduit
is done through a hot oil system and a temperature sensor operably coupled to a controller.
21. The method of claim 18, wherein the body has a non-linear configuration.
22. The method of claim 18, wherein the conduit comprises a thermally conductive material.
23. The method of claim 18, wherein the conduit comprises a non-wetting coating to prevent
the oxidation of aluminum.
24. The method of claim 18, wherein the conduit has a funnel shape.
25. A system for converting molten metal to semi-solid metal comprising:
means for coupling a conduit to a die casting machine, wherein the conduit comprises
an inlet, an outlet and a body disposed between the inlet and the outlet;
means for regulating the conduit's temperature;
means for surrounding the conduit with a housing; and
means for cooling the molten metal to semi-solid metal in the body.
26. The system of claim 25, wherein the means of regulating the temperature of the conduit
is done through a heater, a cooler and a temperature sensor operably coupled to a
controller.
27. The system of claim 25, wherein the step of regulating the temperature of the conduit
is done through a hot oil system and a temperature sensor operably coupled to a controller.
28. The system of claim 25, wherein the body has a non-linear configuration.