This machine is ideal automatic welding machine for straight seams, (web: www-dot-jinanjili-dot-com, email:jilimachine-at-gmail-dot-com)which can automatically weld many kinds of beam-type metals with width 800mm, height 300mm and length 8000mm, and has the best welding results and ideal welding efficiency. This machine can simultaneously weld two straight seams at one work piece. It is the ideal automatic welding machine on truck longitudinal beams and H-beams automatic submerged-arc welding machine.