Malleable cast iron: suitable for water, steam, air oil medium with nominal pressure of PN ≤ 2.5MPa temperature of 30 ~ 300 ℃. Common brands are kth300-06, kth330-08 kth350-10.
Ductile iron: suitable for water, steam, air, oil other media with PN ≤ 4.0Mpa temperature of - 30 ~ 350 ℃. Common brands are:
QT400-15、QT450-10、QT500-7。 In view of the current domestic technology level, the quotation of excavator casting is uneven among manufacturers, it is often difficult for users to inspect. According to experience, it is recommended that PN ≤ 2.5MPa, steel valve is still used as safety valve.
Acid resistant high silicon ductile iron: suitable for corrosive medium with nominal pressure of PN ≤ 0.25MPa temperature lower than 120 ℃.
Carbon steel: suitable for water, steam, air, hydrogen, ammonia, nitrogen petroleum products with nominal pressure of PN ≤ 32.0mpa temperature of - 30 ~ 425 ℃. Common brands are WC1, WCB, ZG25, high quality steel 20, 25, 30 Low Alloy Structural Steel 16Mn.
Copper alloy: suitable for water, sea water, oxygen, air, oil other media with PN ≤ 2.5MPa, steam media with temperature of - 40 ~ 250 ℃. The common brands are zgnsn10zn2 (tin bronze), H62, HPb59-1 (brass), qaz19-2, qa19-4 (aluminum bronze).
High temperature steel: suitable for steam petroleum products with nominal pressure PN ≤ 17.0mpa temperature ≤ 570 ℃. Common brands are ZGCr5Mo 1cr5m0
Zg20 CrMoV, zg15gr1mo1v, 12CrMoV, wc6, wc9 other brands. The specific selection must be in accordance with the valve pressure temperature specifications.
Low temperature steel, suitable for medium such as nominal pressure PN ≤ 6.4Mpa, temperature ≥ 196 ℃, ethylene, propylene, liquid natural gas, liquid nitrogen, etc., commonly used brands) are ZG1Cr18Ni9, 0Cr18Ni9, 1Cr18Ni9Ti, zg0cr18ni9.
Stainless acid resistant steel is suitable for medium such as nitric acid acetic acid with nominal pressure of PN ≤ 6.4Mpa temperature of ≤ 200 ℃. The common brands are zg0cr18ni9ti zg0cr18ni10, zg0cr18ni12mo2ti, zg1cr18ni12mo2ti < acid urea resistant.