The most commonly used metals that CKV hoods are manufactured from are Stainless Steel, and Aluminized Steel.
304 Stainless Steel for Canopy Hood
Streivor’s standard is to build the hood canopy using high quality 304 Grade Stainless Steel. 304 Stainless Steel is a non-magnetic alloy that has lower carbon to minimize carbide precipitation and is used in high-temperature applications. Its resistance to corrosive acids makes it ideal for cookware, appliances, sinks and tabletops.304 grade stainless steel is comprised of no more than 0.8% carbon and at least 50% iron. The chromium binds oxygen to the surface of the product to protect the iron from oxidation (rust). Nickel also enhances the corrosion resistance of stainless steel. Therefore, the higher the nickel content, the more resistant the stainless steel is to corrosion.
430 Stainless Steel for Canopy Hood
430 is in the “Ferritic” group of stainless steels, containing more chromium, no nickel, and carbon from .6% to 35%. It is magnetic and does not respond to heat-treatment. SS 430 has good corrosion resistance and is highly resistant to atmospheric oxidation and strong oxidizing solutions. It can be readily drawn and formed, and it is weldable by common techniques. Type 430 contains a negligible amount of nickel (0.75%) and therefore has a reduced corrosion resistance (is more likely to rust than 18/8 or 18/10 but still high quality) and is magnetic.
Aluminized Metal For Plenum Construction
Aluminized steel is standard steel with a thin coating of aluminum on the inside and outside. The aluminum forms an oxide layer to keep the steel beneath from corroding. Aluminized stainless steel is made of pure steel containing a certain percentage of nickel and chrome, which keeps the material from corroding under any conditions. This material is far cheaper and a bit lighter than stainless steel, making it the default choice for most exhaust systems. However, even a tiny scratch in the aluminum oxide finish can allow the metal beneath to rust, and the cut pipe ends remain exposed to air and moisture.
