As for flat roll of F4 ~ F6 stands, their pre-grinding crowns were optimized and the flatness of strips was greatly improved.

对F4 ~ F6机架平辊的预磨凸度进行优选，明显改善了带钢的平直度。

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Keep your feet flat on the floor, roll your shoulders back and keep your ears directly over them so your head isn't tilted forward.

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All of this is served on a particular roll baked for the express purpose, a round, flat bun derived from a traditional Sicilian bread.

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