Patent ID: 6454884
Filing Date: 2002-09-24
Classification: B21D,B60J,Y10S

Abstract:
A process for making a structural beam, comprising the steps of:feeding a continuous, low-strength steel sheet having opposing side edges in the lengthwise direction thereof; notching the steel sheet at predetermined intervals to define alternating notched and un-notched sheet portions in the lengthwise direction of the sheet; roll-forming the steel sheet in the lengthwise direction to form an elongate profile wherein the un-notched portions are formed into three-dimensional profile sections having walls that meet to define a tube; fixedly connecting the meeting walls of the un-notched portions together to rigidly close the tube; heat treating the profile to substantially increase the strength of the steel defining solely the un-notched portions; and forming the notched portions into flanges which are integrally and monolithically joined to opposite ends of the tube which extends throughout the un-notched portion.