Selecting steel for a metal belt: when 304 is enough, and when 316 or a heat-resistant alloy is required

AISI 302 / 304 - the standard for most processes

302 and 304 steel are the first choice for dry thermal processes and typical food without aggressive media. In Twentebelt Eyelink and Wire Mesh belts, 304 works from -80 to +350 °C and is food-contact approved.

AISI 316 - when chlorine, salt or acids appear

The molybdenum addition in 316 significantly increases pitting-corrosion resistance. It's the right choice for cleaning with aggressive agents, contact with brine, marinades, acidic products and in chemical and pharmaceutical environments.

Rule of thumb: if the process involves chloride (salt) or low pH, assume 316 - the belt price difference is small against the cost of downtime and replacing a corroded belt.

Heat-resistant alloys - above +500…+600 °C

For the highest temperatures (glass furnaces, heat treatment, sintering), Spiral Woven balanced weaves are used, including the Rod Reinforced (RR) type working up to +1200 °C, made of heat-resistant alloys.

Here durability depends not only on peak temperature, but also on the process atmosphere (oxidising/reducing) and heating cyclicity - so material selection is discussed individually.

Watch out for mixed materials

Combining a stainless-steel belt with carbon-steel chains requires a separate cleaning procedure (steam/hot water, no citric acid, which corrodes carbon steel). This is a common source of 'the belt is rusting' complaints that actually concern the C-steel components.