摘要 |
There is disclosed a method and apparatus for adjusting the thickness of a hollow tubular member to provide a cross-section of constant area, such adjustment being inversely dependent upon detected increases or decreases in the thickness of the metal strip. The method and apparatus provide for the formation and welding of a metal strip into a hollow tubular member; the application of longitudinally directed, braking or pushing forces to the hollow tubular member; and then the continuous reduction of the hollow tubular member to achieve a cross-section of constant area. |