To provide a die composed of materials which are suitable to blow molding.
A molding die 14 is constituted by dividing the die into a central die 16 having a product shape part 13 and a peripheral die 17 enclosing the central die 16, the material of the central die 16 is made of cast steel and the material of the peripheral die 17 is made of cast iron. The material of the central die 16 having the product shape part 13 is made of the cast steel. The carbon component of the cast steel is 0.1-0.4% as against the carbon component of the cast iron is 3-5%. Further, the carbon is aspherical and there is no possibility that the carbon is fallen off from the surface of the die because the cast steel has ferritic and pearlitic structure. Furthermore, the surface of the cast iron is roughened by repeating shotblasting, but there is no possibility that the surface is roughened even when the shotblasting is repeated because the cast steel has the properties of steel and its structure is dense. Then, it is disappeared that aluminum is deposited on the central die and there is no possibility that the product is damaged.
YOKOYAMA YASU
SHINODA HIROYUKI
OSA TOSHIHIRO
KONDO TAKASHI
| JPH06304674A | 1994-11-01 | |||
| JPH09168828A | 1997-06-30 | |||
| JPH06238355A | 1994-08-30 | |||
| JP2004255424A | 2004-09-16 |
Tamiya Hiroshi
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