# NAICS 333131: Mining Machinery and Equipment Manufacturing

Breadcrumb: [NAICS codes](https://bidrover.com/naics) › [333131 Mining Machinery and Equipment Manufacturing](https://bidrover.com/naics/333131)

This U.S. industry comprises establishments primarily engaged in (1) manufacturing underground mining machinery and equipment, such as coal breakers, mining cars, core drills, coal cutters, and rock drills, and (2) manufacturing mineral beneficiating machinery and equipment used in surface or underground mines.

- NAICS code: 333131
- Title: Mining Machinery and Equipment Manufacturing
- Sector: 31-33 Manufacturing
- Subsector: 333 Machinery Manufacturing
- Industry group: 3331 Agriculture, Construction, and Mining Machinery Manufacturing
- NAICS industry: 33313 Mining and Oil and Gas Field Machinery Manufacturing
- SBA size standard: 900 employees
- Open bids on BidRover: 0

## Open bids (0)

No open bids cite this code right now.

## Frequently asked questions

### What is NAICS code 333131?

NAICS 333131 is "Mining Machinery and Equipment Manufacturing" in the 2022 North American Industry Classification System, in sector 31-33 (Manufacturing). This U.S. industry comprises establishments primarily engaged in (1) manufacturing underground mining machinery and equipment, such as coal breakers, mining cars, core drills, coal cutters, and rock drills, and (2) manufacturing mineral beneficiating machinery and equipment used in surface or underground mines.

### What is the SBA size standard for NAICS 333131?

A business is small under NAICS 333131 at or below 900 employees, including affiliates (13 CFR 121.201). Confirm the standard named in each solicitation.

### How many government bids are open under NAICS 333131?

No open bid in BidRover cites NAICS 333131 right now. Many state and local notices do not list a NAICS code, so a keyword alert for this work catches more of them.

### How do I get alerts for NAICS 333131 bids?

Save an alert on this page. A free account gets new matching bids by weekly email; the Team plan ($19/mo) sends daily alerts with match scores, the buyer, source link and documents.

## Related NAICS codes

- [333120 Construction Machinery Manufacturing](https://bidrover.com/naics/333120)
- [333132 Oil and Gas Field Machinery and Equipment Manufacturing](https://bidrover.com/naics/333132)
- [333922 Conveyor and Conveying Equipment Manufacturing](https://bidrover.com/naics/333922)
- [336510 Railroad Rolling Stock Manufacturing](https://bidrover.com/naics/336510)
- [333111 Farm Machinery and Equipment Manufacturing](https://bidrover.com/naics/333111)
- [333112 Lawn and Garden Tractor and Home Lawn and Garden Equipment Manufacturing](https://bidrover.com/naics/333112)

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Code titles and definitions: U.S. Census Bureau, North American Industry Classification System (NAICS), 2022 (https://www.census.gov/naics/). Size standards: U.S. Small Business Administration, Small Business Size Standards, 13 CFR 121.201, eCFR text current as of 2026-10-21 (https://www.ecfr.gov/current/title-13/section-121.201).

BidRover lists bids from official public sources. It is not an issuing authority; confirm the NAICS code and size standard named in each solicitation.