The purpose of this is to feed the molten metal to the mold cavity as the molten metal solidifies and shrinks, and thereby prevents voids in the main casting.

其目的是当熔化金属凝固和收缩时往型腔里补充熔化金属，从而防止在主铸件中产生孔隙。

youdao

He does more of the latter now, perhaps because the cadence of fly-fishing--the rhythmic casting and drifting of the fly--connects him to his blacksmith days and hammers home his main conviction: Means matter more than ends.

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Through a casting company, they found a high-school model and an New York University student to play the main characters in photos and videos.

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