The surface of tin round cans must be smooth and clean, with no obvious foreign matter or debris. The can body must not be angular or burr. The pattern and text on the outer surface should be free from serious scratches, scratches, appearance patterns, and text ink. The hue should be correct and even and bright. The pattern net should be clear and clearly structured. The pattern and text should be clear, complete, and not deformed. Unfavorable problems such as burrs, bubbles, and uneven paint. The pattern and text content of the round cans should be the same as the pattern version, without overprinting or missing printing. Patterns and texts should be overprinted accurately, and overprinting inaccuracies should not exceed 0.5 mm. The tin layer on the wall of the can and the sealing edge shall be complete, without the phenomenon of heap tin and coarse tin, no obvious scratches and rust, and no leakage caused by trachoma.
Round cans shall not have quick openings, false rolls, and large rollovers. They shall not have incomplete crimps, curled teeth, iron tongues, skip seals, curled edges, filler extrusion, sharp edges, and vertical lips. Double lines and other defects caused by head and hemming roller failure.
The cans are required to be evenly lined, and there is no bad line to pull the lid or the easy pull ring to be welded. The easy-pull cans should be in the same horizontal plane with the lower edge of the lid. Circular tank welds should be smooth and beautiful, uniform lap joints, solder joints evenly connected, there must be no welding and breakdown phenomenon, the two sides of the weld joint should be less than 0.5mm, the end of the weld should be less than 0.5mm.
The circular tank cans should be smooth and evenly coated with seams, completely covering the weld seams and voids, completely cured, and free of large air bubbles and exposed iron spots. The round tank paint should be free from falling off, inward flow glue, iron sulfide, no serious curing spots, oxidation ring. The shape of the circular tank should be complete and there should be no deformation such as a can or a horn.