Precision Turned Stainless Steel 304 Food Grade Auger Shaft 25mm 400mm Length Ra 0.8μm

This food grade auger shaft is machined from Stainless Steel 304 (304 (1.4301) food contact) to ±0.02mm in the critical dimensions, then finished by Ra 0.8μm passivated. It is produced on CNC turning centres that are dedicated to small and medium volume precision work, so every dimension on the drawing is generated by the machine rather than by hand fitting. Typical users are engineers who have already been let down by a supplier that quoted a tolerance it could not hold, and who need the part to fit the first time without sorting or rework on the assembly line.

• Food Contact Compliant Finish: Ra 0.8μm passivated surface leaves no crevice for bacterial retention and meets typical food contact audits
• Corrosion Resistance: 304 stainless resists the organic acids and chloride washdown chemistry found in food plants
• Straightness For Bearing Life: 0.05mm per 500mm straightness limits radial load on the end bearings of the auger trough
• Coupling Geometry Held: Bore, keyway and coupling pilot are machined in one setup so the auger runs true after assembly
• Documentation For Audits: Material certificate, passivation record and surface finish readings are supplied for food safety audits

The process route is fixed before metal is cut. Bar stock is verified against the purchase specification and the heat number is logged, then a first article is turned and measured in full. Only after the first article is signed off does the lot run. Critical features on this food grade auger shaft are controlled to ±0.02mm with a process capability target of Cpk 1.33 or better, and the operator checks the feature at a defined frequency with the gauge stated on the control plan. Where the drawing calls for Ra 0.8μm passivated, the finishing step is carried out in house and the result is measured, not assumed. Sample parts go to the CMM for full dimensional verification, and the recorded results ship with the lot as a first article inspection report in PPAP level 3 format when a customer program requires it.

Questions are handled by engineers rather than by sales staff. Our team reviews each drawing for manufacturability, flags features that would drive cost without adding function, and proposes the tolerance band that actually matters for the assembly. That review is free and is returned within 24 hours together with a quotation. When a part fails in the field, we ask for the sample back, section it if needed and report what the failure mechanism was, because a supplier that cannot explain a failure cannot prevent the next one.

• Machines: 50+ CNC units including Swiss type lathes, 3, 4 and 5 axis machining centres and turn-mill centres from Citizen, Star, Doosan and Mazak.
• Quality lab: CMM, 2D vision measurement, roughness tester, hardness tester, salt spray chamber and spectral analyser for material verification.
• Team: 15+ mechanical engineers covering DFM review, process design, fixture design and failure analysis.
• Capacity: 500,000+ precision turned parts per month with stable output and on time delivery tracking.
• Quality system: ISO 9001:2015 certified, SGS audited, material traceability from mill heat to finished part.
• Export experience: parts shipped to 30+ countries across North America, Europe, Japan, Korea and Southeast Asia.

Screw conveyors, food mixing shafts, bakery dough augers, grain handling equipment and pharmaceutical powder feeders.

Parts are degreased, dried and packed so that the surface finish specified above arrives intact. Standard packing is VCI paper or individual PE bag, a partitioned foam tray for form features, and an export grade corrugated carton on a pallet, with the lot number and heat number marked on the outside. Parts are warranted against material and workmanship defects for 12 months from delivery. If a part is found outside the drawing, we replace it at our cost and we pay the return freight for the defective lot. Third party inspection by SGS, BV or TUV can be arranged before shipment at your request, and we work under NDA where drawings are confidential.

Q: Does Ra 0.8μm satisfy food safety audits? A: Most food contact specifications call for Ra 0.8μm or better on product contact surfaces with no crevices. We supply the roughness readings so your audit file has evidence rather than a claim.

Q: Should we specify 304 or 316? A: 304 is fine for dry and mildly acidic product. For high chloride washdown, brine contact or CIP with chlorinated water, specify 316L to avoid pitting.

Q: Can you supply the shaft with the auger flight welded on? A: We machine the shaft and can arrange flight welding and post weld passivation as a purchased operation, with weld inspection reported.

Q: How do you protect the finish during transport? A: Shafts are sleeved in foam and packed in a wooden crate. No adhesive tape is applied to the polished surface.

Q: How do you confirm the Stainless Steel 304 material before it is machined? A: Every bar is checked against its mill certificate with an optical emission spectrometer before it goes to a machine. If the chemistry does not match the grade, the bar is rejected and returned. The certificate for your lot is filed under the heat number and can be sent with the shipment or on request.

Q: What happens if a delivered part measures outside the ±0.02mm tolerance? A: Send the measurement and the lot number. We check the recorded values for that lot, replace the parts at our cost and cover the return freight. Because each critical feature is recorded during production, we can trace the deviation to a tool wear step, a fixture shift or a gauge issue and correct the process before the next lot runs.

Send a 2D drawing, a STEP file or a sample and you will have a manufacturability review and a firm quotation within 24 hours. Trial orders from a single piece are accepted, so the tolerance claim can be checked on your own assembly before a production order is placed.