Patent ID: 9221127
Filing Date: 2015-12-29
Classification: B21C,B23K

Abstract:
1. A method for producing welded tubes from steel, comprising: obtaining measuring values regarding material properties of a strip or metal sheet at different measuring sites along a length and width of the strip or metal sheet by a nondestructive continuous or discontinuous testing; forming an integral characteristic value for the material properties of the strip or the metal sheet as a function of the obtained measuring; determining a degree of homogeneity of the material properties with regard to the length and width of the strip or metal sheet as a function of a variance of the measuring values at the different measuring sites; when a deviation of the measuring values exceeds a predetermined threshold, adjusting process parameters used for producing the welded tubes and/or subjecting the strip or metal sheet to a homogenization process; applying the adjusted process parameters during forming of the strip or metal sheet into a longitudinal or helical open seam tube and during welding of confronting edges of the longitudinal or helical open seam tube.