Specify what touches the oil
Food-Contact Materials & Fabrication Checklist
Do not assume the whole machine is one stainless-steel grade. Define each wetted component and the evidence required for it.
Start with the process duty
Material choice depends on the oil, process chemicals, temperature, cleaning method and local requirements. The order should identify wetted parts separately from the structural frame and decorative covers.
Engineering note: Final ratings, materials, utilities and operating limits must be confirmed in the current technical agreement for the supplied machine.
Practical checklist
Wetted-parts schedule
- Tank shell, bottom and cover
- Agitator, shaft and internal fittings
- Piping, valves, pumps and heat-transfer surfaces
- Filter supports, screens and product outlets
- Gaskets, hoses and seal materials
Fabrication checks
- Welds are continuous and accessible where required
- Internal surfaces avoid sharp traps and unreachable pockets
- Low points can drain
- Product-contact parts can be cleaned and inspected
- Grinding and polishing do not hide cracks or incomplete welds
Evidence to retain
- Approved material schedule
- Material certificate where contractually required
- Fabrication and surface photographs
- Leak or pressure test record where applicable
- Final as-built drawing and parts list
Important limitation
- Stainless steel is not automatically corrosion-proof
- A certificate must match the supplied material and scope
- Cleaning chemicals and temperature affect compatibility
- Local food-contact requirements must be reviewed by the project owner