Cast iron SCH21

  • Cr21 cast iron
  • ChTB1.8 cast iron
  • ChNM1.2 cast iron
  • ChM1.8 cast iron
  • SCI cast iron
  • Cr35 cast iron
  • Cr30 cast iron
  • Cr25 cast iron
  • Cr24 cast iron
  • Cr20CrNi2 cast iron
  • Cr20KhN cast iron
  • Cr20 cast iron
  • Cr18 cast iron
  • Cr15 cast iron
  • Cr10 cast iron
  • Cast iron SCh03Ts01B
  • NKHT pig iron (NKHT)

    • Designation

    Name The value
    Designation GOST Cyrillic СЧ21
    Designation GOST Latin CCh21
    Transliteration SCh21
    By chemical elements -

    Description

    Cast iron SCH21 used: for the manufacture of castings of heads and cylinder blocks in car and tractor construction; machine beds, marking plates, cylinders, valves, machine tools; exhaust pipes, flywheels, fundamental frames, crankcases, covers, working cylinders, blocks, and other critical parts in diesel technology; gears, pulleys, and other machines are significantly loaded items in chemical engineering; casting parts of valves and actuators to it; cast connecting parts for pipelines.

    Note

    Ferritic-pearlitic cast iron.

    Standards

    Name Code Standards
    Cast iron В11 GOST 1412-85
    Pipes of ferrous metals and alloys, cast fittings to them В61 GOST 5525-88, GOST 9583-75
    Cast iron castings (grey and malleable cast iron) В81 OST 24.207.01-90

    Chemical composition

    Standard C S P Mn Cr Si Ni Fe
    GOST 1412-85 2.8-3.4 ≤0.12 ≤0.4 0.5-1.5 ≤0.4 1.3-2.4 ≤0.5 Rest
    Fe is the basis.
    The chemical composition is given on the basis of GOST 1412-54 data and reference literature based on obtaining the required time resistance at break and calculating the carbon equivalent, in GOST 1412-85 the chemical composition is not specified, while it is allowed to make castings from cast iron grade СЧ21 at the request of the consumer. Allowed low alloying of cast iron with various elements (chromium, nickel, copper, phosphorus, etc.).

    Mechanical properties

    σU, MPa HB, MPa
    Castings in cast or heat treated condition for STP М319-95
    ≥210 -
    Part of the connecting piping (sand casting) according to GOST 5525-88 (NV - in the center of a wall)
    ≥150 ≤250

    Description mechanical marks

    Name Description
    σU Limit short-term strength
    HB Brinell hardness number