| 摘要 |
PURPOSE:To form penetration beads having excellent uniformity without defects such as reinforcement of weld, undercut, etc. by providing projections on the surface of a backing material which contacts with the rear surface of the groove of materials to be welded. CONSTITUTION:A solid backing material for one-side welding is constituted by providing continuous or discontinuous projections 11 to the top surface thereof, i.e., the surface which contacts with the rear surface of the groove of materials 4 to be welded. Projections 11a, 11b of a refractory solid material which contacts with penetration beads 5 are melted by the arc heat of welding and a suitable slag layer 6 is formed by such backing material. The penetration beads having excellent uniformity without defects such as reinforcement of weld, undercut, etc. are thus formed. |
