Glossary
Materials and construction
AISI 304 stainless steel
Also known as 304 stainless, SS 304, 18-8 stainless.
AISI 304 (sometimes called 18-8 stainless for its ~18% Cr, ~8% Ni composition) is the most widely-used austenitic stainless steel. In sonic-horn manufacture, 304 is the economy option for external mountings, brackets, accessories and parts that do not see directly corrosive flue-gas chemistry.
Why not 304 everywhere
- Chloride pitting — 304 is vulnerable to localised pitting in chloride-bearing environments (most cement, WtE, biomass and coastal applications). AISI 316 / 316L is preferred.
- Continuous high temperature — 304 begins to scale and lose creep strength above ~500 °C.
For external accessories — mounting brackets, support frames, weatherproof enclosure panels — 304 is cost-effective without compromising horn performance.
Related terms
Related terms
- AISI 316 and 316L stainless steelAISI 316 / 316L molybdenum-bearing austenitic stainless steel is the workhorse material for industrial sonic-horn bells, diaphragms and mountings in moderate-temperature service.
- Bell hornA bell horn is the conical or exponential flare that amplifies and projects sound from an industrial sonic horn's driver into the vessel being cleaned.