| 摘要 |
PURPOSE:To provide a titled forming pattern which prevents the generation of casting defects and to reduce the man-hour for cutting by forming a supporting runner which reinforces the runners of the pattern of a heat resistant inorg. ceramic material or metallic material to provide the constitution that withstands the impact during charging of a molten metal to said runner. CONSTITUTION:A pattern for forming a casting mold for precision casting is constituted of a sprue 1, runners 2, cavities 3 and a supporting runner which reinforces the runners 2. The runner 4 of such pattern is formed of a heat resistant inorg. ceramic material or ferrous or non-ferrous metallic material to prevent the generation of the crack in the shell mold in a pattern removing stage and to suppress the failure of the shell mold owing to the pressure and thermal impact of the molten metal during the charging thereof and further to permit easy cutting in the supporting runner part after casting. Al2O3, SiO2, MgO, glass fibers, carbon fibers or the composite compd. thereof are used for the heat resistant inorg. ceramic material of the runner 4 and a metallic material, etc. that can adapt themselves to the metallic material to be charged are adequately used for the ferrous or non-ferrous metallic material. |
