This means that you'll be able to search for NAICS codes directly (if that's your jam). We'll do the math; let's make better data on public procurement together.
Crucible Furnaces; Cupola Furnaces.
Food Industry Ovens (FSC 7310); Metal Heat Treating Furnaces (FSC 3424); Laboratory Type Furnaces (FSC 6640).
Possible NAICS Codes
333994 – Industrial Process Furnace and Oven Manufacturing
333310 – Commercial and Service Industry Machinery Manufacturing
325998 – All Other Miscellaneous Chemical Product and Preparation Manufacturing
811310 – Commercial and Industrial Machinery and Equipment (except Automotive and Electronic) Repair and Maintenance
333415 – Air-Conditioning and Warm Air Heating Equipment and Commercial and Industrial Refrigeration Equipment Manufacturing
333414 – Heating Equipment (except Warm Air Furnaces) Manufacturing
238220 – Plumbing, Heating, and Air-Conditioning Contractors
334516 – Analytical Laboratory Instrument Manufacturing
334513 – Instruments and Related Products Manufacturing for Measuring, Displaying, and Controlling Industrial Process Variables
334413 – Semiconductor and Related Device Manufacturing