Stainless is the metal most often undersold, because sellers assume it is just shiny steel. The grades look identical and price very differently, so we test rather than estimate.
The grades we buy
304 (18/8)
The most common austenitic stainless. Catering equipment, sinks, worktops, brewery and dairy vessels, general fabrication. Around 18 per cent chromium and 8 per cent nickel, and the nickel is where most of the value sits.
316
Contains molybdenum for better corrosion resistance, and is worth more than 304. Common in chemical processing, marine, pharmaceutical and food plant. Visually indistinguishable from 304, which is exactly why testing matters.
430 and other ferritic grades
Little or no nickel, and priced well below 304. Appliance panels, trim, some catering equipment. Magnetic, unlike 304 and 316.
The magnet test, and its limits
A magnet will distinguish ferritic grades such as 430, which are magnetic, from austenitic 304 and 316, which mostly are not. It will not tell 304 from 316, and cold working can make 304 slightly magnetic and confuse the result. It is a useful first sort, not a grading method. We use handheld XRF for anything that matters, and you are welcome to watch it being tested.
What reduces the price
Mild steel frames, brackets and fixings on catering equipment are deducted. Insulation, plastic panels, motors and electrical components in appliances all come off. Heavy scale or product residue inside process vessels is deducted, and vessels that held anything hazardous need declaring before collection.
Preparing stainless for collection
- Separate obviously magnetic material from non-magnetic as a first pass.
- Strip mild steel frames from sinks and worktops where practical.
- Clean out process residue from tanks and vessels.
- Tell us the original use of any chemical or pharmaceutical plant.
- Keep 316 separate if you know which items it is.