A method of forming a flat bar is provided. A tube is provided having an inside surface and an outside surface. The outside surface of the tube can be clad with a nickel or stainless alloy material. A helix shaped strip can be cut from the tube. The helix shaped strip can be uncoiled to form an uncoiled strip, and the uncoiled strip can be straightened and flattened to meet mill standards.

Apparatus and method for forming a plurality of elongate members into a helical bundle. The apparatus has a plurality of bending die heads that are mounted in a circular array within a rigid housing. The bending die heads each have a pair of grooved rollers that engage the sides of the tubes to apply a bending force while allowing the tubes to move longitudinally through the bending die stock. The bending die heads can be rotated about their longitudinal axes to impart a helical twist to the tubes as they pass through the bending die stock. The apparatus also has a collet stock assembly, which consists of a collet that has a plurality of apertures equal to the number of tubes in the bundle to be formed. The collet stock is mounted to a housing that is secured to a carriage. The carriage is driven by motor and lead screw to move linearly along a track toward and away from the bending die stock while the collet is rotated at a predetermined speed to form a helical bundle.