Process and device for bending elongated articles

摘要

A process and a machine for bending elongated articles wherein the article is led progressively past a heating device heating a small band of the article, the bending taking place in said band, wherein for controlling the thickness of a wall portion lying in the bend one measures the longitudinal speed of said still unbent wall portion before this reaches the heating device and likewise the speed after this wall portion has passed the heating device, and adjusts the distribution of the temperature in the heating zone of the band by changing the heating pattern in dependence on the relation between said two speeds.