NAICS 331512

Overview

The North American Industry Classification System (NAICS) is the federal standard for classifying business establishments to support statistical collection, analysis, and publication about the U.S. economy. Developed under the Office of Management and Budget with the U.S. Economic Classification Policy Committee, Statistics Canada, and Mexico’s INEGI, NAICS replaced SIC in 1997; the current structure is organized under the 2022 vintage. ¹

NAICS 331512 covers establishments primarily engaged in producing steel investment castings using the investment (lost‑wax) process. Investment molds are made by coating a wax pattern with refractory slurry, removing the wax, and casting steel into the resulting mold; cleaning and similar foundry operations may be performed, but firms that further manufacture into finished products are classified by the finished product industry. ²

See also on G2X:

• NAICS 331513 Steel Foundries (except Investment)
• NAICS 331511 Iron Foundries

What this NAICS covers

• Production of steel investment castings as the primary activity. ²
• Fabrication of investment molds from wax patterns and refractory slurry for steel casting. ²
• Melting and pouring steel into investment molds to create complex, high‑detail castings. ²
• Foundry finishing steps such as cleaning and deburring of castings. ²
• Purchasing steel inputs made in other establishments rather than producing primary steel. ²
• Classifying the establishment to the finished‑product industry when castings are further manufactured into specific end products. ²

Related NAICS and PSC codes

Type	Code	Descriptor
NAICS	331513	Steel Foundries (except Investment). 2
NAICS	331511	Iron Foundries. 2
NAICS	33151	Ferrous Metal Foundries (industry group encompassing iron and steel foundries). 2

Scope notes and cross‑references

• Steel castings made by methods other than investment casting are classified in NAICS 331513. ²
• Establishments that make steel investment castings and then machine/assemble them into specific finished products are classified by the finished product industry, not in NAICS 331512. ²
• Foundries may perform cleaning and deburring on the castings they produce; more involved machining that transforms castings into finished products is classified elsewhere in manufacturing. ²

NAICS 2022 usage in federal data

Census Bureau economic programs are transitioning to the 2022 NAICS vintage; First Look 2022 Economic Census data began release in 2024, with most NAICS‑based programs adopting 2022 by the end of 2027. This context informs how data for NAICS 331512 appear across official datasets. ³

Frequently asked questions

• What activities define NAICS 331512?

  • Establishments primarily make steel investment castings using the lost‑wax process: creating refractory molds from wax patterns, removing the wax, and casting steel. Foundry finishing like cleaning and deburring is included. Further manufacturing into finished products is classified elsewhere. ²

• How does NAICS 331512 differ from NAICS 331513 and NAICS 331511?

  • 331512 is specific to steel investment casting. 331513 covers steel castings made by other methods, and 331511 covers iron foundries. All are in the ferrous foundries group, but classified by metal and process. ²

• Are machining or assembly operations included under NAICS 331512?

  • Foundries may clean and deburr their castings. When operations like machining, threading, or assembly transform castings into finished products, the establishment is classified in the industry of the finished product, not in 331512. ²

• What is NAICS and why does the 2022 vintage matter here?

  • NAICS is the tri‑national industry classification system used by U.S. federal statistical programs; it was adopted in 1997 and is updated every five years. Census is implementing the 2022 vintage across programs through 2027, affecting how industry data are tabulated and published. ³

Useful resources

• U.S. Census Bureau: NAICS 331512 — Steel Investment Foundries (definition and cross‑references). ²
• Census: The Census Bureau’s Implementation of the 2022 NAICS (scope and timeline). ³
• Census: NAICS Codes & Understanding Industry Classification Systems (background and concepts). ⁴
• 2022 Economic Census — Manufacturing (Sector 31–33) data tables and documentation. ⁵

References

1. U.S. Census Bureau — Classifying Businesses: Adoption and development of NAICS (1997 background). https://www.census.gov/about/history/historical-censuses-and-surveys/census-programs-surveys/economic/classifying-businesses.html
2. U.S. Census Bureau — NAICS Sector 31–33, including 331512 Steel Investment Foundries (definitions and cross‑references). https://www.census.gov/naics/resources/archives/sect31-33.html
3. U.S. Census Bureau — The Census Bureau’s Implementation of the 2022 NAICS (definition, changes, and transition timeline). https://www.census.gov/library/reference/code-lists/naics/2022/implementation-timeline.html
4. U.S. Census Bureau — Economic Census: NAICS Codes & Understanding Industry Classification Systems. https://www.census.gov/programs-surveys/economic-census/technical-documentation/code-lists/understanding-naics-redirect.html
5. U.S. Census Bureau — 2022 NAICS Sector 31–33 Manufacturing (Economic Census data access). https://www.census.gov/data/tables/2022/econ/economic-census/naics-sector-31-33.html