当板材焊接后会出现焊缝。从较微观的角度分析焊缝：它是直边而不是弧边它是

When the plate is welded, a weld will appear. <br>Analyze the weld seam from a more microscopic perspective: <br>it is a straight edge instead of an arc edge, <br>it is a thick edge instead of a thin edge, <br>it is rough instead of smooth, and in <br>general, it not only increases the friction between the upper and lower rollers. And the torque of the lower roller is also increased. <br>Therefore, we must polish the weld before the rounding, not too thick. <br>Secondly, the rolling must be carried out step by step. <br>These require not only theoretical calculations, but also empirical guidance. 

Welds occur when the sheet is welded.<br>Analysis of welds from a more microscopic perspective:<br>It is a straight edge, not an arc.<br>It is thick rather than thin.<br>It is rough rather than smooth.<br>Taken together, it not only increases the friction of the upper and lower rollers. And the torque of the lower roller swells is increased.<br>Therefore, we should polish the welds before rolling round, not too thick.<br>Second, the roll must be rolled in a step-by-step manner.<br>These require not only theoretical calculations, but also empirical guidance. 

When the plate is welded, the weld will appear.<br>From the microscopic point of view, the welding seam is analyzed<br>It is a straight edge, not an arc edge<br>It's a thick edge, not a thin edge<br>It's rough, not smooth<br>Generally speaking, it not only increases the friction between the upper and lower rollers. And the torque of the lower roller is also increased.<br>Therefore, we should polish the weld before rolling round, not too thick.<br>Secondly, rolling must be carried out step by step.<br>These need not only theoretical calculation, but also experience guidance.<br>