Projection seam welding sheet metal profiles - using resistance welding electrode rollers, without impairing sheet metal surface (NL 3.10.78)

摘要

When sheet metal profiles are welded together, the sheets are first fed through a rolling machine, which forms the desired profiles while also forming a projection on =1 of the profiled sheets; the projection runs along the seam to be welded. The sheets are then fed through rotating electrode rollers to make the weld, and may be subjected to further forming operations. The electrode rollers are pref. fed with current pulses. A pref. plant is used for the projection seam welding of a pipe made by bending metal sheet to form a pipe with a longitudinally seam provided with a projection. The pipe is then welded while support rollers are located in its bore; and the electrode rollers consist of two disks on a common axis, but insulated from each other. The outer and/or visible surfaces of the weld are virtually undamaged so their appearance is not spoiled.