| 摘要 |
PURPOSE:To prevent the chipping, clattering and floating of a strainer by forming a protective layer having a tapered surface coinciding with the inside peripheral face of the cup of a sprue on the side face of the porous strainer body by using dense refractories. CONSTITUTION:The porous zirconia strainer body 1 is inserted into a cylinder 3 made of silicone rubber. The bottom of the rubber 3 is sealed with a bottom plate 6 and wax 42 is poured into the formed space to tightly adhere and hold the strainer body 1. The strainer body 1 is mounted to a cup mold 5 for disposing the strainer of the runner after the solidification of the wax. Slurry refractories are then poured into the spacing thereof. After the refractory slurry solidifies, the solidified refractories are removed from the cup mold 5 and are subjected to dewaxing and calcination of the protective layer by which the strainer for casting is formed. The generation of the defect of the product by chipping is prevented and the casting parts having high quality are obtd. if such strainer is used. |
