Stainless Steel CNC Machining for Food and Dairy Equipment
Fittings, nozzles and machine parts where the finish and the cleaning regime decide as much as the tolerance. Reply within 24 business hours.
We own no machines and we are not a certifying body. Certification of finished equipment to 3-A or NSF is the equipment builder's job. We place your RFQ with partner shops that already machine and finish to those requirements.
One itemised quote, no separate service fee. Only the partner shops that price your part see the drawing. NDA on request.
Start with the environment, not the word food
Writing 304 because it is the grade everybody names is right often enough to be dangerous. What decides it is what the surface actually meets.
304, dry or simple rinse
Comfortable for dry product and a plain water rinse. Machinability near 45, PREN near 19.
- Fittings and housings that stay dry between cleans
- Cheaper to cut than 316L and welds well
- Wrong once chloride from salt, brine or a chlorinated clean is present
316L, chloride present
The molybdenum addition that lifts PREN to about 24. Machinability near 36, slower to cut.
- Salt, brine, cured meat, cheese, citrus and caustic clean in place
- The grade most food and dairy auditors expect by name
- Past continuous brine or sea water processing, see 2205 duplex
Grades that come up in this work
Published typical values. The full table with all six grades is in the grade reference.
| Grade | Machinability | PREN | What it means on the floor |
|---|---|---|---|
| 304 / 304L / 1.4301 | 45 | 19 | The default austenitic. Welds and forms well. Work hardens fast, so a rubbing tool makes the next pass harder than the last. |
| 316 / 316L / 1.4404 | 36 | 24 | Two to three percent molybdenum buys chloride resistance. The grade food, pharma and medical buyers ask for by name, and the slowest of the common three to cut. |
| 2205 duplex / 1.4462 | 30 | 35 | Around twice the yield strength of 316L and far better in chloride. Slow, hard on tools and worth it only when the part needs it. |
Finish and standards, in short
3-A Sanitary Standards, the reference most food and dairy equipment in North America is built to, call for product contact surfaces at 32 microinch Ra or better, about 0.8 micrometre, plus geometry a brush can actually clean.
- Ra 0.8 micrometre or better on product contact surfaces
- Internal corners radiused, not sharp, so a brush reaches them
- No blind threads or crevices in product contact areas
- Passivated to ASTM A967, citric, with certificate
- 303 and other free-machining grades kept off the print entirely
Typical parts
- Dairy and beverage fittings and nozzles
- Valve bodies, seats and stems
- Filter housings and manifolds
- Pump and mixer shafts
- Conveyor and processing line hardware
- Clean-in-place system components
Keep reading
- Materials
Choosing stainless for parts that touch food
The full decision tree, standards and drawing language for food contact.
- Process
Citric against nitric passivation
Why citric is the usual choice for food and medical work now.
- Materials
303, 304 and 316L compared
The machinability and corrosion trade behind the three most common grades.
- Process
Machining stainless weldments
Where a weld joint becomes the crevice an auditor flags.
- Process
3-A sanitary standards for machined parts
What the standard actually asks of a component, not just the equipment.
Questions about food and dairy work
Something else? Email .
Is 304 acceptable for food contact parts?
For dry product and simple water rinse, usually yes. Once the part meets salt, brine, citrus, tomato or a chlorinated clean in place, chloride is present and 316L is the safer specification. Write the actual environment in the RFQ rather than the word food and let the grade follow from it.
What does 3-A actually require from a machined part?
The 3-A Sanitary Standards that most North American food and dairy equipment is built to call for product contact surfaces at 32 microinch Ra or better, about 0.8 micrometre, plus cleanable geometry with no sharp internal corners or crevices. A machined component inside a 3-A system usually has to meet that finish even when the component itself is not separately certified.
Why is 303 kept off food contact parts even though it looks like 304?
The manganese sulphide stringers that make 303 cut fast are the same inclusions that open into pits and hold residue once the surface is polished. That fails a cleanability audit even when the tolerance is perfect.
Do you supply parts that already carry an FDA or NSF certification?
We place RFQs with partner shops that machine to the grade, finish and documentation you specify. Certification of the finished equipment is the equipment builder's job, not a machined component's, and it is not something we or any single shop can certify on your behalf.
What should go on the drawing for a food contact part?
The grade with its specification, the Ra number on product contact surfaces and the passivation standard and method, plus the internal corner radius. That is quotable. Food grade, polished is not, and the quotes you get back for it will not be comparable.
Have a food or dairy equipment drawing ready?
Send the short version now. Name the finish and passivation standard your part needs, and we will ask for anything else missing.