Vertical type pressure casting method

摘要

A method of casting including the steps of closing gates with a counter tip after lower and upper molds heated to a predetermined temperature have been clamped, pouring melt into a sleeve in which a plunger tip is lifted a predetermined distance, lowering the plunger tip while displacing the counter tip to a predetermined position to open the gates, which are formed such that the ratio of the volume of products to the cross-sectional area of the gates is 20-40 (i.e. the volume of products/(CM3) cross-sectional area of gates (CM2)=20-40), to allow the melt to flow into cavities via the gates by the force of gravity alone with the plunger tip reaching the upper surface of the melt the moment a percentage of the melt placed in the cavities has reached a value between 30 and 70%, and pressure-filling the cavities with the melt by the plunger tip with the melt passing through the gates at 0.4-0.8 m/sec.