Structure of NAICS Code 331 - Primary Metal Manufacturing
Hierarchy
Each industry is classified hierarchically, starting from broad (3-digit) to specific (4-, 5-, 6-digit) codes, including extended 8-digit codes for detailed classification. Click on each category link to navigate to detailed pages with comprehensive industry information.
Categories
General
Specific
Hierarchy
3-Digits
4-Digits
5-Digits
6-Digits
3311 - Iron and Steel Mills and Ferroalloy Manufacturing
33121 - Iron and Steel Pipe and Tube Manufacturing from Purchased Steel
33122 - Rolling and Drawing of Purchased Steel
3312 - Steel Product Manufacturing from Purchased Steel
331313 - Alumina Refining and Primary Aluminum Production
331314 - Secondary Smelting and Alloying of Aluminum
331315 - Aluminum Sheet, Plate, and Foil Manufacturing
331318 - Other Aluminum Rolling, Drawing, and Extruding
33131 - Alumina and Aluminum Production and Processing
33141 - Nonferrous Metal (except Aluminum) Smelting and Refining
33142 - Copper Rolling, Drawing, Extruding, and Alloying
3314 - Nonferrous Metal (except Aluminum) Production and Processing
331491 - Nonferrous Metal (except Copper and Aluminum) Rolling, Drawing, and Extruding
331492 - Secondary Smelting, Refining, and Alloying of Nonferrous Metal (except Copper and Aluminum)
33149 - Nonferrous Metal (except Copper and Aluminum) Rolling, Drawing, Extruding, and Alloying
331511 - Iron Foundries
331512 - Steel Investment Foundries
331513 - Steel Foundries (except Investment)
33151 - Ferrous Metal Foundries
331523 - Nonferrous Metal Die-Casting Foundries
331524 - Aluminum Foundries (except Die-Casting)
331529 - Other Nonferrous Metal Foundries (except Die-Casting)
33152 - Nonferrous Metal Foundries