we are manufactring tube mill. IN tube mill there is a machine shear and welder . it is used to weld the last end of going coil and front end of coming coil. for smmoth welding we shear some part of bot strips then weld it so it is called shear n welder. now what we r doing is to put these two strips manully so as to any gap between them for proper welding. but we want this process also be automated means we want that when the edge of two strips just join welding should start .highly precision is required as any deviation from edge cause defects.