Parts for Metal Rolling Mills (Except Rolls)

This line targets extremely large structural components — such as mill housings or backup roll chocks — that are cast or welded as single units weighing more than 90 metric tons. The distinction matters because these items may carry a different duty rate than general mill parts under 8455908000. Importers should obtain the manufacturer's certified weight documentation and confirm the component is a casting or weldment (not a machined or fabricated assembly) before applying this line.

CBP applies the 'principal use' and 'dedicated use' tests: a part classifiable as a rolling mill part must be identifiable by its design as suitable for use solely or principally with rolling mills of heading 8455. Generic bearings, seals, or fasteners that are interchangeable across many machine types generally classify in their own headings rather than as mill parts. Technical drawings and the OEM's parts catalog are the primary supporting documents.