| 摘要 |
PURPOSE:To obtain many products all at once with good dimensional accuracy by making a model by making a female die for forming a wax model of a hollow engine valve, assembling the wax model, forming a mold by dewaxing by coating and casting a molten metal. CONSTITUTION:A wax model is made by pouring a wax into a female mold and a tree 30 is obtd. by assembling it. The tree 30 is then dipped in a slurry, refractory particulates are sprinkled over and a refractory layer is coated. When a mold 36 is formed around the tree 30, the wax model is started to be melted and after baking it at high temp. a molten metal 38 is poured and a product is taken off. The piercing by a drill thus becomes unnecessary, the external body and piercing can simultaneously be performed, the dimensional accuracy in piercing is good as well and many products is obtd. with good efficiency all at once.
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