Methods for bending thin-walled tubes

A method for bending a thin-walled tube to form a small radius bend on the thin-walled tube, the method comprising:

• (a) providing a die defining a curved cavity enclosed within, wherein the curved cavity is configured to receive the thin walled tube;
• (b) lubricating the thin-walled tube, wherein an antifriction coating material comprising Molybdenum disulfide, is applied on an exterior surface of the thin-walled tube for reducing friction between the exterior surface of the thin-walled tube and the curved cavity of the die;
• (c) extruding the thin-walled tube into a curved section from an insertion end of the die, wherein the curved section is configured to form the small radius bend on the thin-walled tube;
• and
• (d) thrusting elastomer fillers into an inner surface of the thin walled tube via a mandrel, wherein the mandrel is forced from an end distal to the insertion end of the die against the thin-walled tube to prevent damage of the inner surface of the thin-walled tube to form the small radius bend.