Rolling machines can be used to make various construction components, such as corrugated metal tiles, keel, universal Angle iron, curtain guide rails, metal doorframe etc.

用滚压成型辘机可以做出各种各样的建材构件，如金属波纹瓦片、龙骨、万能角钢、窗帘导轨、金属门框等。

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The daggerboard is a type of keel beneath the boat that allows the boat to sail at an angle into the wind.

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