PURPOSE: To improve a mechanical property of a mold in a high temp. region and improve the reclaiming characteristic of the used molding sand by containing burn- up type fiber materials of the specific shape to a facing sand part at the time of molding the mold with the molding sand added with a binder.
CONSTITUTION: A flask 2 is placed on a molding board 1, and a wooden pattern 3 is set therein. Paper pieces 5 as a burn-up type fiber material are beforehand added to facing sand 4 and the mixture is kneaded. This facing sand 4 is acattered on the surface of the wooden pattern 3. Next, backing sand 6 is charged and is rammed to mold a sand mold. The paper pieces 5 to be added to the facing sand 5 are formed to such shapes that the ratio of long side to short side is ≥3. The paper pieces 5 penetrate in the backing sand 6 before the facing sand 4 is hardened thereby mechanically binding the facing sand 4 and backing sand and improving the strength of the mold. In addition, when molten metal is poured into the mold, the paper pieces burn off completely and do not leave any harmful components in the used molding sand and therefore a high proportion thereof is reusable.
| JP7189016 | Polyurethane binder containing alcohol solvent |
| JPH09122819 | SWEEPING MOLD TYPE MOLDING METHOD |
HAGIWARA HITOSHI
NOGUCHI HIROSHI
YAMADA TSUNEO
SOGABE AKIRA
