COLLISION ENERGY ABSORBING STEEL PIPE AND METHOD FOR MANUFACTURING THE SAME

PROBLEM TO BE SOLVED: To provide a novel collision energy absorbing steel pipe exhibiting a sufficient collision energy absorbing characteristic and capable of coping even with an installation space of a deformed cross section, and to provide a method for manufacturing the same. SOLUTION: This collision energy absorbing steel pipe has a multiple tube structure for inserting a plurality of inside steel pipes 2 inside an outside steel pipe 1, and the outside steel pipe 1 is press-fitted to an outer peripheral surface of the inside steel pipes 2 by drawing. Among the inner peripheral length of the outside steel pipe 1, the sum of the noncontact length with the inside steel pipes 2 is 20% or less of the inner peripheral length. The inside steel pipes 2 may be a cross-sectional circular steel pipe, and may also be a cross-sectional non-circular deformed steel pipe, and are suitable for a bumper and a door impact beam of an automobile. COPYRIGHT: (C)2010,JPO&INPIT