Stamped and welded process for making steel rectangular or square tubular parts and parts therefrom

Abstract

A method of making steel square and rectangular pipe employs a die stamping operation to score steel plate and a machine to forming such parts.

What is claimed is: 
     
         1 . A method of making steel square pipe includes the steps of:
 providing a generally planar steel plate with equal length opposing sides and having a predetermined thickness, a front surface and a back surface, a first longitudinal edge and a second longitudinal edge, and a first transverse edge and a second transverse edge;   scoring a plurality of lines longitudinally across the back surface, wherein a first longitudinal score line is a first predetermined length X from the first longitudinal edge defining a first longitudinal section, a second longitudinal score line adjacent and parallel the first longitudinal score line is the predetermined length X therefrom defining a second longitudinal section, a third longitudinal score line adjacent and parallel the second longitudinal score line is the predetermined length X therefrom defining a third longitudinal section, and also is the predetermined length X from the second longitudinal edge defining a fourth longitudinal section; and   applying sufficient forces on the first longitudinal section and the second longitudinal section in a manner to form approximately 90 degree bend at the first longitudinal score line and applying sufficient forces on the fourth longitudinal section and the third longitudinal section in a manner to form approximately 90 degree bend at the third longitudinal score line, applying sufficient forces on the second longitudinal section and the third longitudinal section in a manner to form approximately 90 degree bend at the second longitudinal score line thereby causing the first and second longitudinal edges to abut to form square steel pipe.   
     
     
         2 . The method of making steel square pipe of  claim 1 , which includes applying a weld surface on the first and second longitudinal edges. The method can include smoothing the weld surface. 
     
     
         3 . The method of making steel square pipe of  claim 2 , which includes smoothing the weld surface. 
     
     
         4 . The method of making steel square pipe of  claim 1 , which includes employing a stamping tool having a die face configured to score all said scoring lines at once. 
     
     
         5 . The method of making steel square pipe of  claim 4 , wherein said die face further includes a tool surface for making at least one opening in at least one said longitudinal section. 
     
     
         6 . The method of making steel square pipe of  claim 5 , wherein said die face further includes at least two tool surface for making at least two opening in at least two said longitudinal sections. 
     
     
         7 . The method of making steel square pipe of  claim 6 , which is further characterized such that said die face further two tool surface are configured for making at least two coaxially aligned openings in at least two said longitudinal sections. 
     
     
         8 . A method of making steel rectangular pipe includes the steps of:
 providing a generally planar steel plate with equal length opposing sides and having a predetermined thickness, a front surface and a back surface, a first longitudinal edge and a second longitudinal edge, and a first transverse edge and a second transverse edge;   scoring a plurality of lines longitudinally across the back surface, wherein a first longitudinal score line is a first predetermined length X from the first longitudinal edge defining a first longitudinal section, a second longitudinal score line adjacent and parallel the first longitudinal score line is a second predetermined length Y therefrom defining a second longitudinal section, a third longitudinal score line adjacent and parallel the second longitudinal score line is a second predetermined length  2 X therefrom defining a third longitudinal section, and a fourth longitudinal score line adjacent and parallel the third longitudinal score line is the predetermined length Y therefrom defining a fourth longitudinal section and the fourth longitudinal score line is the predetermined length X from the second longitudinal edge  128  defining a fifth longitudinal section;   applying sufficient forces on the first longitudinal section and the second longitudinal section in a manner to form an approximately 90 degree bend at the first longitudinal score line and applying sufficient forces on the fifth longitudinal section and the fourth longitudinal section in a manner to form an approximately 90 degree bend at the fourth longitudinal score line, and further includes applying sufficient forces on the second longitudinal section and the third longitudinal section in a manner to form approximately 90 degree bend at the second longitudinal score line and applying sufficient forces on the third longitudinal section and the fourth longitudinal section in a manner to form approximately 90 degree bend at the third longitudinal score line thereby causing the first and second longitudinal edges and to abut to form a rectangular pipe.   
     
     
         9 . The method of making steel square pipe of  claim 8 , which includes applying a weld surface on the first and second longitudinal edges. The method can include smoothing the weld surface. 
     
     
         10 . The method of making steel square pipe of  claim 9 , which includes smoothing the weld surface. 
     
     
         11 . The method of making steel square pipe of  claim 9 , which includes employing a stamping tool having a die face configured to score all said scoring lines at once. 
     
     
         12 . The method of making steel square pipe of  claim 11 , wherein said die face further includes a tool surface for making at least one opening in at least one said longitudinal section. 
     
     
         13 . The method of making steel square pipe of  claim 12 , wherein said die face further includes at least two tool surface for making at least two opening in at least two said longitudinal sections. 
     
     
         14 . The method of making steel square pipe of  claim 13 , which is further characterized such that said die face further two tool surface are configured for making at least two coaxially aligned openings in at least two said longitudinal sections. 
     
     
         15 . A steel pipe, which includes a steel plate formed with at least four sides of equal length and having opposing sections of equal width wherein all sides have a predetermined thickness, including two outermost sections welded together at a respective outermost edge thereof, and each remaining section integrally connecting to another section generally at a 90 degree bend and having a scoring line internally formed longitudinally across an internal surface which serves to impart said 90 degree bend.