Cast Iron: A general‐purpose material suitable for water, air, petroleum products, most solvents, dry powders, and a wide variety of chemicals when used in the unlined state. This can also be lined with various rubbers and plastics to handle almost any process media.
Ductile Iron: A general‐purpose material with usage similar to cast iron. Ductile iron however is much stronger and more capable where there may be high pipeline stresses, danger from impact, or concern from leakage upon line or valve fracture. Normally, ductile iron can be used as a direct replacement for steel valves. Can be lined with a wide variety of rubbers and/or plastics to handle almost any process media.
Steel: Another general‐purpose material that is somewhat resistant to corrosion then cast iron especially where water is the media. Steel is much stronger and like ductile iron much more capable where there may be high pipeline stress, danger from impact, or concern from leakage upon line or valve fracture. Can be lined with a wide variety of rubbers and/or plastics to handle almost any media.
Stainless Steel: An alloy of iron, carbon, nickel, and chromium. Suitable for most foods, beverages, pharmaceuticals, solvents, sea water, oils, and some acids and alkalis.
Alloy 20: Has higher amounts of nickel and chromium then 300 series stainless steels. It is mores resistant to sulfuric acid and is used widely in chemical processing and water treatment
Bronze: Has a higher strength than pure copper. It is generally accepted as an industry standard for pressure rated valves and fittings. It is very resistant to pitting corrosion, with general resistance to most chemicals.