> Enrich.chat gives AI agents verified work emails and mobiles. To use it from an agent, read https://enrich.chat/agents.md . This is the Markdown version of https://enrich.chat/sic/3321/ # SIC code 3321: Gray and ductile iron foundry The companies classified under SIC 3321, where they are based, how big they are and how the code maps to NAICS. By Enrich.chat Editorial. Updated October 22, 2026. **Short answer:** SIC 3321 is the Standard Industrial Classification code for Gray and ductile iron foundry, in division D (Manufacturing). The companies counted under it are mostly small: 72% have 200 or fewer employees. ## What is SIC 3321? SIC 3321 is the Standard Industrial Classification code for Gray and ductile iron foundry. It sits in division D, Manufacturing. The first two digits name the major group, and the last two narrow it to a single industry. Most of the companies counted also carry NAICS 331511 (92%). - 41% of the companies counted have 50 or fewer employees, and the middle one is in the 51 to 200 range. - The largest group is headquartered in the United States (57%). - Most were founded in the before 1960 (67%), then the 1960s (9%). **Figure: How SIC 3321 is built.** The code 3321 split into its parts: major group 33, then industry group and industry. It sits in division D, Manufacturing. *The four digits of SIC 3321.* ## Which companies are classified under SIC 3321? The biggest by headcount range include Waupaca Foundry, Menon And Menon, Simplex Castings, Monarch Industries and Neosym Industry. Names link to a company profile where we have one. | Company | Headquarters | Employees | | --- | --- | --- | | Waupaca Foundry | Waupaca, WI | 1,001 to 5,000 | | Simplex Castings | Bhilai, India | 501 to 1,000 | | Monarch Industries | Winnipeg, Canada | 501 to 1,000 | | Neosym Industry | Pune Maharashtra India., India | 501 to 1,000 | | Gießerei Heunisch | Bad Windsheim, Germany | 501 to 1,000 | | Employee Owned Brands | Fairfield, IA | 501 to 1,000 | | Bci Solutions | Bremen, IN | 201 to 500 | | Great Lakes Castings | Ludington, MI | 201 to 500 | | Charter Dura-Bar | Woodstock, IL | 201 to 500 | | Spilrod - Fundição De Ferro E Aço Ltda | Nova Veneza, Brazil | 201 to 500 | | Acme Foundry | Coffeyville, KS | 201 to 500 | | Rochester Metal Products | Rochester, IN | 201 to 500 | | Osco Industries | Portsmouth, OH | 201 to 500 | | Prospect Foundry | Minneapolis, MN | 51 to 200 | | Faircast | Fairfield, IA | 51 to 200 | | Pier Foundry & Pattern Shop | St. Paul, MN | 51 to 200 | | Torrance Casting | La Crosse, WI | 51 to 200 | | Penn-Mar Castings | Hanover, PA | 51 to 200 | | Kirsh Foundry | Beaver Dam, WI | 51 to 200 | | Leda Werk GmbH & Co. Kg | Leer Ostfriesland, Germany | 51 to 200 | | Dakota Foundry | Webster, SD | 51 to 200 | | Decatur Foundry | Decatur, IL | 51 to 200 | | Ellwood Engineered Castings | Hubbard, OH | 51 to 200 | | Benton Foundry | Benton, PA | 51 to 200 | | The Taylor & Fenn | Windsor, CT | 51 to 200 | The table shows the 25 biggest by headcount range, with ties broken by audience size. The charts and percentages below cover every company counted for this page, not just these 25, and companies with fewer than 11 employees are not counted. Headquarters is the location on each company's public profile. ## Where are SIC 3321 companies based? The largest groups are headquartered in the United States (57%), Germany (17%) and India (9%). **Figure: Where companies in SIC 3321 are based.** Bars for the share of counted companies in SIC 3321 headquartered in each country: United States 57%, Germany 17%, India 9%, Brazil 6%, Canada 6%. *Share of counted companies in SIC 3321 by headquarters country.* ## How big are the companies counted for SIC 3321? 41% of them have 50 or fewer employees, and the middle one is in the 51 to 200 range. Companies with fewer than 11 employees are not counted. **Figure: Size of companies in SIC 3321.** Seven columns for the share of counted companies in SIC 3321 in each employee range: 11 to 50 41%, 51 to 200 31%, 201 to 500 15%, 501 to 1,000 10%, 1,001 to 5,000 3%, 5,001 to 10,000 0%, 10,001+ 0%. *Share of counted companies in SIC 3321 in each employee range.* ## How SIC 3321 compares - 41% of companies in SIC 3321 have 50 or fewer employees, against 60% across all NAICS codes on this site. ## SIC 3321 and the NAICS system NAICS replaced SIC as the U.S. federal standard in 1997, but the two do not line up one to one. These are the NAICS codes seen most among the companies counted under SIC 3321. | Code | Title | Share of counted | | --- | --- | --- | | NAICS 331511 | Iron Foundries | 92% | | [NAICS 333994](https://enrich.chat/naics/333994/) | Industrial Process Furnace and Oven Manufacturing | 4% | | [NAICS 336390](https://enrich.chat/naics/336390/) | Other Motor Vehicle Parts Manufacturing | 4% | ## How do SIC 3321 companies describe themselves? A code is assigned by classification, and a company does not choose its own, so the label a company uses for itself can differ. The most common labels here are Mining (44%), Machinery Manufacturing (20%) and Industrial Machinery Manufacturing (11%). **Figure: How companies in SIC 3321 describe themselves.** Bars for the share of counted companies in SIC 3321 that give each industry on their public profile: Mining 44%, Machinery Manufacturing 20%, Industrial Machinery Manufacturing 11%, Fabricated Metal Products 5%, Manufacturing 5%, Retail 5%. *Share of counted companies in SIC 3321 by the industry they list on their public profile.* ## Where SIC codes come from SIC was created in the 1930s and is now historical: the U.S. government replaced it with NAICS in 1997. It is still widely used, and the SEC still assigns a SIC code to every company that files on EDGAR. The full list is in the [SIC manual](https://www.osha.gov/data/sic-manual) that OSHA hosts, and the Census Bureau's [guide to understanding NAICS](https://www.census.gov/programs-surveys/economic-census/year/2022/guidance/understanding-naics.html) explains how the two relate. ## How do you reach the people at SIC 3321 companies? The people to talk to are usually operations, supply chain and procurement leaders. You can build the list in three prompts to your AI agent. ### 1. Count them (free) Counting who matches never uses credits. ```text Use www.enrich.chat to count the companies with SIC code 3321 (Gray and ductile iron foundry) ``` ### 2. Find the people (5 credits per person) Name the roles you sell to. Each person returned is 5 credits, and name, title and company are included. ```text Use www.enrich.chat to find the operations, supply chain and procurement leaders at companies with SIC code 3321, with their titles ``` ### 3. Get their work emails (10 credits each) An email is 10 credits only when one is found. Every email comes with a status: verified, catch-all or unknown. ```text Use www.enrich.chat to find the work emails for these people and tell me which ones are verified ``` ## Frequently asked questions ### What is SIC code 3321? SIC 3321 is the code for Gray and ductile iron foundry, in division D (Manufacturing). ### What is the NAICS code for SIC 3321 (Gray and ductile iron foundry)? 92% of the companies counted carry NAICS 331511 (Iron Foundries), but the two systems do not map one to one. ### Which companies are classified under SIC 3321? The biggest by headcount range include Waupaca Foundry, Menon And Menon, Simplex Castings, Monarch Industries and Neosym Industry. The page lists 25 with links to their profiles where we have them. ### How big are the companies in SIC 3321? 41% have 50 or fewer employees, and the middle one is in the 51 to 200 range. Companies with fewer than 11 employees are not counted. ### Is SIC still used? Yes. The U.S. government replaced SIC with NAICS in 1997, but SIC codes are still common in business databases, and the SEC still uses them on EDGAR. ## Try this prompt Find the people at SIC 3321 companies ```text Use www.enrich.chat to find the operations, supply chain and procurement leaders at companies with SIC code 3321, with titles and verified work emails ``` ## Related - [Companies using a technology](https://enrich.chat/companies-using/) - [Tech stack lookup](https://enrich.chat/tools/tech-stack-lookup/)