| 摘要 |
1,072,924. Making metal sheet. BRITISH ALUMINIUM CO. Ltd. Aug. 25, 1964 [Aug. 30, 1963], No. 34421/63. Headings B3A and B3M. Metal sheet is produced by extrusion, whereby a number of rows of parallel ribs and possibly mounting flanges 3 are formed. The extruded sheet is passed between a roll 5, which may be of laminated wood and freely rotatable, and a driven roll 6 of hardened tool steel. The teeth (9) of the roll 6 (Fig. 5, not shown) form grooves in the ribs at an angle to the length thereof. |
