摘要 |
A method for corrugating a metal foil (11), which together with a longitudinally flat foil (12) is intended to form a foil package pervious to liquid or gas, where the folds are made with a very small fold radius by rolling in at least two steps between rollers (42, 43) disposed in pairs, the fold radius (51) being large and the fold height (52) low in a first step, and after the final step, the fold radius (53) is less than 10%, preferably 2 to 5% of the fold distance (55), and the fold height (54) is greater than after the first step. <IMAGE> |