| 摘要 |
<p>The present invention relates to rounded corrugated sheeting (4) whose profile exhibits crest portions (5), flanks (6), and bottom portions (7). The crest portions (5) are located on the concave side of the rounded sheet and are provided with grooves formed by pressing during rounding of the sheeting. The grooves form ribs (10) on the convex side of the sheet. In the rounding of the sheet, the material present in the crest-portions (5) of the sheet (4) is distributed in a manner which facilitates rounding and counteracts the formation of folds or wrinkles in the crest portions (5), and prevents other forms of damage.</p> |
