| 摘要 |
The casting device (1) comprises a pump (6) conveying molten light metal from a holding furnace (not shown) through a reservoir (9) via a nozzle (10) to an inlet system (5) in a mould (4) with a view to filling a mould cavity (3) in said mould (4). The mean cross-sectional area (A) of the reservoir (9) is substantially greater than the mean cross-sectional area a of the inlet (5) in the mould (4), and the length of the reservoir (9) constitutes a major proportion of the distance between the pump (6) and the mould (4). With this arrangement, the kinetic energy of the flowing metal within the reservoir (9) is reduced and consequently the total kinetic energy to be braked when the flowing metal during filling the mould cavity (3) passes a constriction in the latter, and in case of the eventual filling of the mould. This means that the amplitudes of the pressure rises created in the flowing metal under such conditions are also reduced considerably, thus avoiding local expansion of the mould cavity (3) due to such pressure rises. In an embodiment (not shown), the reservoir (9) may comprise a pocket of entrapped gas, this reducing further the amplitudes of the said pressure rises.
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