Method for making a beam from a metal sheet

A method for making a beam from a metal sheet, comprising:

• providing a metal sheet having opposite first and second side edges extending longitudinally along opposing sides of the metal sheet, and first and second generally parallel opposing face surfaces provided between said first and second edges, said first and second generally parallel opposing faces defining a thickness of said metal sheet there between;
• splitting the thickness of said metal sheet at one of the first and second side edges to form first and second integral flanges from a portion of the metal sheet such that inner ends of said first and second flanges remain integrally connected with an unsplit portion of said metal sheet;
• bending said first and second flanges so as to provide said metal sheet with a tubular portion extending along one side of and integrally formed with said unsplit portion;
• and
• then fixing said first and second flanges against movement relative to one another,
• wherein bending of said first and second flanges so as to provide said metal sheet with said tubular portion extending along said one side of said unsplit portion is performed by bending said first and second flanges so that the free ends of said first and second flanges are bent towards said unsplit portion and disposed adjacent said first and second face surfaces of said metal sheet so that said tubular portion comprises a pair of tubes extending along the one side of said unsplit portion, and
• wherein fixing said first and second flanges is performed by securing free ends of said first and second flanges to said first and second opposing face surfaces of said metal sheet respectively.