| 摘要 |
<p>Iron bath tubs are produced by casting between two half-moulds with a protective film applied to the surface of each, placed face-to-face to form the mould cavity. The plane of the joint is vertical with the metal feed channel between the two half-moulds into the rim of the bath in the upper part of the mould. The cast iron is distributed along the rim into that part of the cavity which forms the side of the bath, inclined to the horizontal. Uniformly then casting is mfd., without local thickening of the base where the feed channel enters in the conventional inverted position. Easy escape of gas which is no longer trapped in the horizontal base ensures a sound casting. The protective film reinforces the sand mould against the pressure head of molten metal and gives a good surface finish for enamelling.</p> |
