| 摘要 |
<p>A method is provided for producing a spiral-formed exhaust tube (12). Material (14) having spaced-apart first and second edges (50, 52) and a die (86) having a groove (96) are provided. Louvers (32) are formed in the material (14). The material (14) is rolled into a tube using the die (86) so that the louvers (32) extend outwardly away from a longitudinal axis (84) of the tube (12). The louvers (32) pass through the groove (96) of the die (86) as the material (14) is rolled into the tube (12). The first and second edges (50, 52) of the material (14) are then connected.</p> |
