PURPOSE: To allow a vent hole to leave no trace behind on the surface of a product and also, to prevent the occurrence of the casting defect such as pin hole in the product at the time of casing plural cast iron-made pipe joints by using a die device consisting of a vertical split die and collapsible cores loosely fitted in plural product cavities formed on the joint surface of the dies.
CONSTITUTION: The vent holes communicated with core print receivers 11 in the horizontal direction in the vertical split die are arranged. Further, the dimension of the cross sectional area of an ingate provided in core prints 18 in the horizontal direction of the collapsible core 5 is defined as 5.0-7.5% of the cross sectional area of a main sprue 6. On the wall surfaces of the product cavities 4 and sprue systems 6, 7, 9, basic coating and working coating are applied at 0.1-0.2mm and 0.05-0.1mm thicknesses respectively.
ANDO YUKIICHI
NAKAMOTO IKUHIKO
SAWA YOSHIKI
NAGAI TAKESHI
HIGASHIO MEC KK