Rolling is a method of forcing profiles such as, aluminum extrusions and sheet metals, into permanently curved shapes of pre-determined contour.
A roll bender typically has three rollers used to form a metal bar into a circular arc. The rollers freely rotate about three parallel axis, which are arranged with uniform horizontal spacing. Two outer rollers, usually immobile, cradle the bottom of the material while the inner roller, whose position is adjustable, presses on the topside of the material.
When a part is curved without the influence of being stretched, two natural forces take place in the part. One-half of the part will naturally be stretched, while the other half will naturally go into compression and the neutral axis is the point that divides them. Rolling does not have the higher accuracy of stretch forming, however works well for steel tubes, angles, channels, etc. As well as standard profiles.
With rolling you can roll partial arcs, rings, spirals and continuous curves well over 360 degrees.
Techniform maintains an assortment of three wheel roll machines, including CNC equipped rolls. We can roll up to 8" steel profiles, and are well versed in rolling aluminum shapes as well. We currently roll aluminum bar, T's, Angles and miscellaneous shapes for various aircraft stringer and spar programs.