Explanatory notes
… 73.03 ‑ Tubes, pipes and hollow profiles, of cast iron. This heading applies to tubes, pipes and hollow profiles … be socketed, flanged integrally or flanged by welding or threading. To facilitate assembly, socketed pipes have one … the end of a second pipe. Flanged pipes can be assembled by means of collars, nuts, bolts, clamps, etc., while threaded …