U.S. Copper Rolling, Drawing, Extruding, and Alloying (NAICS 33142): Investor Rollup

1. Overview

North American Industry Classification System (NAICS) code 33142 is the five-digit industry covering plants that convert copper, copper scrap and copper alloys into semi-finished shapes — rod, tube, sheet, strip, plate, wire, foil, powder and similar products.[1] It sits between miners, refiners and recyclers upstream and electrical, construction, transportation and industrial customers downstream.

This is a conversion business, not a direct bet on the copper price: operators earn a spread for processing metal, controlling quality, managing scrap and delivering the right specification on time. Few U.S.-listed companies are pure plays, so public investors get only partial exposure — and the revised child primer makes clear that the remaining public routes are mostly diversified or foreign-listed — while private investors have more direct routes through family mills, employee-owned producers and sponsor-backed platforms.

2. What's inside — and why this level equals its one child

NAICS 33142 contains exactly one six-digit national industry:

Because there is a single child, the five-digit industry (33142) and the six-digit industry (331420) describe the same activity, the same plants and the same companies. This page is a short rollup: it states this level's own federal figures and points you to the full 331420 primer for the detailed treatment of structure, economics, named companies, regulation and risk.

The boundary matters more than the code count. Integrated primary smelting and refining (331410), copper die-casting (331523), fabricated wire products made from purchased wire (33261), insulating purchased wire (335929) and scrap wholesaling without metal recovery (423930, 562920) all sit outside this level — a plant that draws copper and then insulates it, however, can stay inside it.[1] Treating this level as "the U.S. copper industry" is the single most common analytical error, because mining and primary refining are excluded.

One useful distinction the five-digit Economic Census adds: it publishes firm-level data, whereas County Business Patterns counts establishments (plants). This level reports 211 establishments but only 135 firms, confirming that a single owner often runs several plants — a "plant" is not a "company."[2][4] Note that the child primer's exact six-digit extract publishes no firm count at all; see the data-availability note in section 3.

Scale here is industrial even where it is legally "small": the Small Business Administration size standard for this industry is 1,050 employees, so a substantial mill can still qualify as small for certain federal programs.[5]

3. Size (this level's rollup figures)

Two federal programs cover this exact industry. County Business Patterns (CBP) gives employment and payroll; the 2022 Economic Census (EC) gives receipts and firm counts at the five-digit level.

The last figure is an analytical ratio, not full compensation per full-time-equivalent worker: CBP measures employment around March while payroll covers the whole year.

A disagreement worth naming. The revised 331420 primer reports that the federal extract it works from publishes no exact six-digit revenue, value of shipments, firm count, concentration ratio or Herfindahl–Hirschman Index, and it deliberately declines to infer suppressed values.[4] The receipts, firm-count and concentration figures on this page come from the five-digit cut of the same Economic Census program.[4] Because this level has exactly one child, the two describe the same plants, so the difference is one of publication coverage, not of scope: the five-digit series is published, the six-digit series is not. Read the five-digit values as the only published cut, and do not expect a matching table in the child primer.

Physical-flow context. Federal establishment counts are not the only way to size the industry. The U.S. Geological Survey reports that the United States consumed 1.7 million metric tons of refined copper in 2025, with apparent consumption of primary refined copper plus copper recovered from old scrap at 2.2 million metric tons, feeding roughly 30 brass mills, 14 rod mills and several hundred foundries and miscellaneous manufacturers.[6] Those plant counts are grouped by physical process, not by Census primary-business classification, so they are context for this level rather than a substitute for its 211 establishments.

Undercount caveat. CBP principally covers establishments with paid employees; it excludes nonemployers and most government activity.[3] That can understate industries dominated by tiny owner-operated shops. Editorial judgment: the effect should be modest here because copper processing is capital-intensive commercial manufacturing, though the smallest owner-operated businesses still fall outside the totals. The EC receipts figure is a genuine reported value, not an estimate inferred from suppressed cells.

4. Investable universe — where value concentrates

All value at this level sits in the single child, 331420. Within it, the five-digit 2022 Economic Census shows a moderately fragmented industry with a long tail:

The HHI — the sum of each firm's squared market share, where higher means more concentrated — is 527, well below the 1,500 threshold the U.S. Department of Justice and Federal Trade Commission treat as "unconcentrated." On these figures no small group of firms dominates: the top four hold about 37% of receipts, and it takes 50 firms to reach roughly 95%. The child primer, working only from exact six-digit extracts where these values are unpublished, declines to make any concentration claim at all.[4] Both positions are defensible; the honest reading is that the published five-digit evidence points to moderate fragmentation and there is no independent six-digit confirmation of it.

Where the shape has changed most. The revised child sharpens the public universe well beyond the two names this page previously carried:

• Mueller Industries (NYSE: MLI) remains the closest large U.S.-listed operating comparison, though it includes downstream products, aluminum and international operations. Its Industrial Metals segment recorded $1.024 billion of sales, $105.0 million of operating income and a 16.0% gross margin in 2025, with approximately 4,832 employees at year-end, about 1,820 of them union-represented.[7]
• Materion (NYSE: MTRN) is the specialty, qualification-driven profile — high-performance copper and nickel-alloy strip, rod, wire, bar, plate and tube — diluted by other segments.[8]
• Prysmian (Milan: PRY) now owns Encore Wire's vertically integrated Texas copper-rod, wire and cable operations, acquired for approximately $4.2 billion and delisted in 2024.[9]
• Aurubis (Frankfurt/Xetra: NDA) brings direct U.S. recycling exposure through its Richmond, Georgia, facility, inside a group dominated by global smelting and refining.[10]
• Steel Dynamics (NASDAQ: STLD) converts reclaimed copper into rod and wire through SDI LaFarga Copperworks but does not disclose that operation's results separately.[11]

The defining feature of this level is how private it is. Southwire is Richards-family-owned, with an integrated Georgia copper-rod operation capable of more than 380,000 metric tons annually.[12][13] Wieland is family-controlled and absorbed the last U.S.-listed pure play when it bought Global Brass and Copper at $44 per share in 2019.[14] International Wire Group, backed by Olympus Partners, completed its acquisition of Hussey Copper in 2025.[15] Revere Copper Products is employee-owned.[16] Foreign- and conglomerate-owned mills fill out the roster — see the 331420 primer, section 4, for the full list. Direct public pure-play exposure largely disappeared with the Global Brass and Encore Wire transactions; what remains is exposure by segment, not by company.

Upstream miners and copper ETFs express the direction of the metal price. They are not representatives of this level, whose operators earn conversion spreads and can be hurt by rising metal prices through working capital.

5. How the money works

Identical to the child. A simplified selling price is metal cost + conversion charge + product premium + freight. Copper cathode and scrap prices drive reported revenue and working-capital needs but not necessarily profit; the metric that matters is the conversion margin (value added after removing pass-through metal), alongside tons shipped, capacity utilization, product mix, scrap yield and inventory days. First-in, first-out (FIFO) inventory accounting can shift margins between periods, and Mueller states directly that pass-through timing and FIFO move margins between periods.[7] Materion reports "value-added sales" net of pass-through metal for exactly this reason.[8]

A concrete benchmark for fabricator economics, carried over from the child: Global Brass and Copper earned a 10.6% gross margin, a 5.3% operating margin and $128.5 million of adjusted EBITDA on $1.765 billion of sales in 2018 — a 7.3% adjusted EBITDA margin — though its mix included distribution and some non-copper processing, so this is not an industry average.[17]

No exact-code capacity-utilization series exists. The broader primary-metals category (NAICS 331) ran at 66.7% utilization in 2025, against 67.0% in 2024 and 73.0% in 2022 — a directional proxy only.[18] The industry Producer Price Index rose from 169.332 in February 2026 to 178.822 in June 2026, about 5.6%, which indicates rising realized prices but proves nothing about volume or margin.[19] See the 331420 primer, section 5, for the full economics.

6. Demand drivers

Same as the child, now with a measured end-use map. Copper's U.S. end-use mix in 2025 was building construction 42%, electrical and electronic products 23%, transportation 18%, consumer and general products 10%, and industrial machinery 7%.[6] Grid investment, data-center power demand and transportation electrification are the constructive medium-term drivers: the Energy Information Administration forecasts electricity demand growth of 1.9% in 2026 and 2.5% in 2027, with data centers an important contributor,[20] and the International Energy Agency's stated-policies scenario projects global clean-technology copper demand rising from 7.737 million metric tons in 2024 to 10.910 million metric tons in 2030.[21] Both are forecasts of demand, not of fabricator sales.

Recycling is structurally important and is where mill-level cost advantage is built. USGS estimates 760,000 metric tons of new (manufacturing) scrap and 160,000 metric tons of postconsumer scrap generated in 2025; brass and wire-rod mills consumed roughly 80% of recovered copper, and recycled material supplied about 30% of total U.S. copper supply.[6] Supply security cuts the other way: net import reliance was an estimated 57% of apparent U.S. copper consumption in 2025, so more domestic processing capacity does not remove dependence on imported refined metal.[6] Detail is in the 331420 primer, section 6.

7. Regulation

Same as the child. Environmental rules are plant-specific: the Environmental Protection Agency regulates copper-forming wastewater under 40 CFR Part 468, covering cleaning, pickling, annealing, cooling and lubrication streams;[22] secondary copper smelters may face National Emission Standards for Hazardous Air Pollutants, including particulate controls and scrap-management requirements;[23] and the Occupational Safety and Health Administration sets permissible exposure limits of 0.1 milligram per cubic meter for copper fume and 1 milligram per cubic meter for copper dusts and mists.[24] Enforcement is not theoretical — Hussey Copper's 2021 federal-state wastewater settlement carried an $861,500 penalty plus required management measures.[25]

Trade policy is now a major variable, and an unstable one. An April 2026 proclamation imposed Section 232 tariffs on listed copper goods, generally 50% for core copper articles, 25% for certain other articles and substantial derivatives, and 10% for qualifying products under its U.S.-origin-metal provisions;[26] a June 2026 revision changed parts of the qualification framework.[27] Copper was added to the final U.S. critical-minerals list in 2025, strengthening the policy case for domestic capacity.[28] Editorial judgment: the fact that the regime was amended within two months is itself the lesson — tariff economics should not be capitalized as permanent. See the 331420 primer, section 7.

8. Consolidation

Same as the child. Recent deals — Wieland/Global Brass and Copper (2019, $44 per share), Prysmian/Encore Wire (2024, approximately $4.2 billion) and International Wire Group/Hussey Copper (2025) — show continuing consolidation, and each removed or absorbed a U.S. listing.[9][14][15]

The sharper structural description the child now supplies is that this industry is concentrated within individual product families but fragmented across the category: wire rod, brass rod, rolled strip, copper tube and specialty alloys need different equipment, furnaces and customer qualifications, so a leader in one is often absent from another. That reconciles with the five-digit concentration data above (HHI 527, CR4 36.6%), which describes the category as a whole and would not detect dominance inside a single product family. Dense metal is expensive to move, so well-located mills hold an advantage with nearby customers and scrap suppliers regardless of national share.

9. Risks

Same as the child: metal-price and working-capital swings, pass-through lag and FIFO effects, cyclical construction and durable-goods demand, substitution (aluminum in conductors, PEX in plumbing, fiber in telecommunications, and material-efficiency engineering),[6] scrap availability and quality, import dependence on refined copper, tariff and policy risk, operational hazards (fires, furnace outages, casting failures, product defects) and legacy environmental liabilities. The revised child adds two the parent previously omitted: labor risk — skilled furnace operators, metallurgists and maintenance staff are scarce, and union negotiations at legacy plants affect costs — and customer concentration, since large utilities, distributors and original-equipment manufacturers exercise real purchasing power. Full list in the 331420 primer, section 9.

10. How to invest & outlook

Because this level is identical to 331420, the approach is the same. MLI offers the broadest U.S.-listed fabrication exposure and MTRN a specialty-materials profile; PRY and NDA provide foreign-listed access whose U.S. copper operations are small parts of larger groups; STLD's copper-rod business is not separately disclosed. Private routes are more direct. Value these businesses on normalized conversion earnings and free cash flow, not copper-driven headline revenue, and underwrite private deals by separating metal value from conversion revenue, normalizing inventory gains and losses, quantifying maintenance capital and environmental reserves, and stress-testing debt capacity against a copper-price working-capital shock.

Forward judgment: the demand backdrop is constructive — grid buildout, data-center power and electrification — but more copper demand does not automatically produce better returns. The winners are low-cost, well-located commodity mills with strong scrap loops, or specialty producers whose alloys and qualifications create switching costs. The thesis is operational execution, not a call on copper's outright price. Guard against the four errors the child names: treating this level as "the U.S. copper industry" when mining and primary refining are excluded; inferring profitability from copper prices; treating Census shipment value as economic value added without removing passed-through metal; and blending fabrication with downstream fittings, insulated cable or distribution in public-company analysis. For the complete how-to-invest and diligence checklist, see the 331420 primer, section 10.

Sources

1. U.S. Census Bureau, "2022 NAICS Definition: 331420—Copper Rolling, Drawing, Extruding, and Alloying," 2022. https://www.census.gov/naics/?details=331420&input=331420&year=2022
2. U.S. Census Bureau, "2023 County Business Patterns: United States," 2025. https://www2.census.gov/programs-surveys/cbp/datasets/2023/cbp23us.zip
3. U.S. Census Bureau, "County Business Patterns Methodology," 2025. https://www.census.gov/programs-surveys/cbp/technical-documentation/methodology.html
4. U.S. Census Bureau, "2022 Economic Census, Concentration of Largest Firms (EC2200SIZECONCEN)," 2025. https://api.census.gov/data/2022/ecnsize/groups/EC2200SIZECONCEN.html
5. U.S. Small Business Administration, "Table of Small Business Size Standards," 2023. https://www.sba.gov/document/support-table-size-standards
6. U.S. Geological Survey, "Mineral Commodity Summaries 2026: Copper," 2026. https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-copper.pdf
7. Mueller Industries, "Annual Report for the Year Ended December 27, 2025," 2026. https://www.sec.gov/Archives/edgar/data/89439/000008943926000008/mli-20251227.htm
8. Materion Corporation, "Annual Report for the Year Ended December 31, 2025," 2026. https://www.sec.gov/Archives/edgar/data/1104657/000110465726000011/mtrn-20251231.htm
9. Prysmian, "Prysmian Completes Acquisition of Encore Wire," 2024. https://www.prysmian.com/en/media/press-releases/acquisition-of-encore-wire
10. Aurubis, "Aurubis Richmond," 2026. https://www.aurubis.com/richmond
11. Steel Dynamics, "Annual Report for the Year Ended December 31, 2025," 2026. https://www.sec.gov/Archives/edgar/data/1022671/000110465926021395/stld-20251231x10k.htm
12. Southwire, "Family Owned," 2026. https://www.southwire.com/family-owned
13. Southwire, "SCR Copper Rod Systems Brochure," 2026. https://www.southwire.com/medias/SCR-Copper-Brochure.pdf
14. Wieland, "Wieland Group and Global Brass and Copper Complete Merger," 2019. https://www.wieland.com/en/about/news/wieland-group-and-global-brass-and-copper-complete-merger
15. International Wire Group, "International Wire Group Completes Acquisition of Hussey Copper," 2025. https://internationalwire.com/blog/international-wire-group-completes-acquisition-of-hussey-copper/
16. Revere Copper Products, "About Revere," 2026. https://reverecopper.com/about-revere/
17. Global Brass and Copper, "Annual Report for the Year Ended December 31, 2018," 2019. https://www.sec.gov/Archives/edgar/data/1533526/000153352619000032/brss-12312018x10k.htm
18. Federal Reserve Board, "Capacity Utilization: Manufacturing—Primary Metal," 2026. https://fred.stlouisfed.org/series/CAPUTLG331A
19. U.S. Bureau of Labor Statistics, "Producer Price Index by Industry: Copper Rolling, Drawing, Extruding, and Alloying," 2026. https://fred.stlouisfed.org/series/PCU331420331420
20. U.S. Energy Information Administration, "U.S. Electricity Demand Forecast to Continue Growing," 2026. https://www.eia.gov/todayinenergy/detail.php?id=67344
21. International Energy Agency, "Global Critical Minerals Outlook 2025: Copper," 2025. https://www.iea.org/reports/copper-2
22. U.S. Environmental Protection Agency, "Copper Forming Effluent Guidelines," 2026. https://www.epa.gov/eg/copper-forming-effluent-guidelines
23. U.S. Environmental Protection Agency, "Secondary Copper Smelting Area Sources: National Emission Standards," 2007. https://www.epa.gov/stationary-sources-air-pollution/secondary-copper-smelting-area-sources-national-emissions
24. Occupational Safety and Health Administration, "Annotated Table Z-1," 2026. https://www.osha.gov/annotated-pels/table-z-1
25. U.S. Environmental Protection Agency, "Federal-State Settlement Resolves Environmental Violations at Hussey Copper Smelting," 2021. https://www.epa.gov/newsreleases/federal-state-settlement-resolves-environmental-violations-hussey-copper-smelting
26. The White House, "Strengthening Actions Taken to Adjust Imports of Aluminum, Steel, and Copper into the United States," 2026. https://www.whitehouse.gov/presidential-actions/2026/04/strengthening-actions-taken-to-adjust-imports-of-aluminum-steel-and-copper-into-the-united-states/
27. The White House, "Further Adjusting the Tariff Regimes for Imports of Aluminum, Steel, and Copper into the United States," 2026. https://www.whitehouse.gov/presidential-actions/2026/06/further-adjusting-the-tariff-regimes-for-imports-of-aluminum-steel-and-copper-into-the-united-states/
28. U.S. Geological Survey, "Interior Department Releases Final 2025 List of Critical Minerals," 2025. https://www.usgs.gov/news/science-snippet/interior-department-releases-final-2025-list-critical-minerals