Patent ID: 6758921
Filing Date: 2004-07-06
Classification: B21D,B60B,B60G,C21D

Abstract:
A method of manufacturing a bending-resistant, torsionally yielding tubular profiled member as a transverse support of a twist beam rear axle of a passenger car, the method comprising the steps of:cold-forming a tube blank of tempering steel to a tubular profiled member with a torsionally yielding central longitudinal section of a U-shaped cross-section and with opposed torsion-proof end sections; annealing transitional sections of the tubular profiled member located between the torsionally yielding central longitudinal section and the opposed torsion-proof end sections at a temperature level between 850Â° C. and 960Â° C.; hardening the tubular profiled member in water at a temperature above the AC3point; tempering the tubular profiled member at a temperature between 200Â° C. and 550Â° C. for a duration of more than five minutes; subjecting the tubular profiled member at least to an outer surface hardening process; and subjecting the tubular profiled member to further configuration processing steps for completing a twist beam rear axle.