A CASTING SYSTEM AIMING FOR BETTER ENVIRONMENT BY USING ELECTROMAGNETIC
MELT SUPPLY AND POWDER LUBRICATION (THE NEW LEOMACS SYSTEM TM ※）
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| In recent years, with the environmental issues for the background, an increasing
number of die casters are trying to improve the existing bad working environment
of the die casting shops, and aiming for the establishment of a die casting
system that is safe and with good environment, which they can be proud
of for the future. In response to such strong need, this casting system
has been developed. For instance, a customer in Taiwan is running the mass
production of master cylinders on this system. Introducing an excerpt of
the paper we presented to the 2002 Japan Die Casting Congress (JD02-32). |
1. Features of this casting system
(1) By doing the die spray and sleeve lubrication with the die closed,
the air blow noise of blowing off excessive die lubricant, the floating
mist from spray and the mixture of a die lubricant drip into the waste
water management system are to be eliminated, improving the shop cleanliness
as well. The machine we used was ＤＸＨＶ３５０. |
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| Conventional spray (left: before spraying; right: during spraying) |
Animation to compare New LEOMACS and old system
（The page to be linked to is to show animations (size: 2Mbyte X 2)
* Patent pending |
| Apply through a hole above ejector pins. |
| Apply through a hole below ejector pins. |
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(2) Using together with electromagnetic melt feed system
| The enclosed-type melt feed system makes it possible to improve environment.
Further more, metal of higher quality can be fed compared to that of ladling. |
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(3) Reducing the machine cycle time
| Die close |
Melt feed |
Injection |
Curing time |
Die open |
Ejection |
Take out |
Spray |
Total |
| 2.7sec |
1.5sec |
2.1sec |
29.0sec |
2.7sec |
1.0sec |
12.0sec |
15.0sec |
66.0sec |
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Casting cycle time using the conventional spray device
| Die close |
Powder |
Melt feed |
Injection |
Curing time |
Die open |
Election |
Take out |
Total |
| 2.7sec |
10.0sec |
1.5sec |
2.1sec |
29.0sec |
2.7sec |
1.0sec |
12.0sec |
61.0sec |
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Casting cycle time using the New LEOMACS system
(4) Effect on plunger sleeve condition
The use of the powder die lubricant makes it possible to apply uniformly
all over the area compare to conventional systems, and to sharply improve
the condition of aluminum-alloy-to-sleeve adhesion.
Die-lubricant buildup, aluminum adhesion, scars are observed.
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| Sleeve on water-soluble die lubricant |
Sleeve on powder lubricant |
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(5) Adequate die plan
For lack of external cooling effect like that of water-soluble die lubricant,
a die temperature rise will occur. If the die temperature should rise too
much, the die-lubricant powder will not adhere to the die. Therefore, die-temperature
control that is considered to be efficient for the powder-lubricant adhesion
is needed.
We reviewed the die-cooling plan using CAE, increased the cooling line
numbers, and managed to make the die temperature adequate.
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| Cooling lines for water-soluble die lubricant |
Cooling lines for powder lubricant |
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2. Conclusion
(1) It is now possible to improve the peripheral working environment remarkably.
(2) Together with the use of the electromagnetic melt feed system, the
production of high-quality castings at high productivity is now possible.
(3) Thanks to the review of the die-cooling plan, the improvement of die-lubricant
adhesion efficiency and the prevention of soldering were achieved, and
acceptable casting-cycle time was obtained.
(4) The adoption of the powder sleeve lubrication made it possible to sharply
improve the condition of aluminum-alloy-to-sleeve adhesion.
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* LEOMACS is a registered trademark of TOSHIBA MACHINE CO., LTD.
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