The slab came back to be flat without opposite curling at the post stage of stacking cooling with heat preservation cover, and the residual stresses decreased.

堆冷过程中加盖保温罩能使铸坯在冷却后期恢复平直而不发生反向弯曲，并且铸坯内残余应力也变小了。

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The Vuitton family has quite a history: Company founder Louis was the first modern trunk-maker to make trunks flat on top (the better for stacking) and lighter (thanks to canvas sides) than the traditional stagecoach trunk.

FORBES: Inside the Louis Vuitton Special-Order Workshop