Non-destructive testing of steel tubes. Digital radiographic testing of the weld seam of welded steel tubes for the detection of imperfections Non-destructive testing, Steels, Pipes, Seamed pipes, Welded joints, Welding, Automatic, Radiographic testing, Flaw detection, Digital recording methods, X-rays, Fusion welding, Arc welding, Longitudinal joints, Grades (quality), Approval testing, Acceptance (approval)