… welded, riveted or similarly closed), having circular cross-sections, the external diameter of which exceeds 406.4 mm, …
Explanatory notes
… welded, riveted or similarly closed), having circular cross-sections, the external diameter of which exceeds 406.4 mm, … edges are welded without filler metal by flash‑welding, by electrical resistance or induction welding, or by submerged arc welding with filler metal and flux or gas protection to prevent oxidation. As regards products …