Cast iron SCH25

  • 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 СЧ25
    Designation GOST Latin CCh25
    Transliteration SCh25
    By chemical elements -

    Description

    Cast iron SCH25 is used: for the manufacture of various castings for critical applications with the lowest allowable wall thickness 15 mm: blocks and cylinder heads, liners, flywheels in automotive and tractor industry; machine beds, machine beds drill rigs, surface plates, cylinders, valves, machine tools, blocks, drums, wheels, bushings, couplings bearings and other thelongitudinal; piston heads, bushings, cylinder covers and other parts operating on the abrasion at elevated temperatures in diesel technology; critical parts working in compression (Bashmakov, columns); boilers for melting caustic soda, pipes, elbows and other parts in chemical engineering, working in solutions and melts of alkalies; casting 2 groups for stationary steam turbines, turbine equipment, nuclear power plants, elements of steam boilers and pipelines, hydraulic turbines, hydraulic valves and other equipment power plant engineering, operating at temperatures up to 250 °C, exposed to high static and dynamic loads and friction (pistons, housings, bearing housings, housings worm wheels, bushings, bearing caps, nozzles, compressors, diaphragms, RAM Foundation, RAM exhaust parts, nozzles, compressors, gear wheels, gear); casting parts of valves and actuators to it; cast connecting parts for pipes; casting parts mining and metallurgical equipment.

    Standards

    Name Code Standards
    Castings with special properties (iron and steel) В83 KSt 81-033:2009
    Cast iron В11 GOST 1412-85, STP М319-95
    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 108.962.01-85, OST 24.207.01-90, OST 23.4.258-86, OST 23.4.117-84, TU 1-812-0072-94

    Chemical composition

    Standard C S P Mn Cr Si Fe
    GOST 1412-85 3.2-3.4 ≤0.15 ≤0.2 0.7-1 - 1.4-2.2 Rest
    KSt 81-033:2009 3.2-3.4 ≤0.15 ≤0.2 0.7-1 - 1.4-2.2 Rest
    STP М319-95 3-3.4 ≤0.15 ≤0.2 0.7-1 ≤0.25 1.5-2 Rest
    Fe is the basis.
    According to GOST 1412-85, low alloying of cast iron by various elements (chromium, nickel, copper, phosphorus, etc.) is allowed.

    Mechanical properties

    Section, mm σU, MPa HB, MPa
    Approximate data on the time resistance to tensile and hardness in the walls of castings according to GOST 1412-85, STP М319-95
    15 ≥250 ≤245
    Castings in cast or heat treated condition for STP М319-95
    - ≥250 180-250
    Approximate data on the time resistance to tensile and hardness in the walls of castings according to GOST 1412-85, STP М319-95
    150 ≥150 ≤156
    Part of the connecting piping (sand casting) according to GOST 5525-88 (NV - in the center of a wall)
    - ≥150 ≤250
    Approximate data on the time resistance to tensile and hardness in the walls of castings according to GOST 1412-85, STP М319-95
    30 ≥210 ≤238
    4 ≥310 ≤260
    50 ≥180 ≤187
    8 ≥270 ≤255
    80 ≥165 ≤170

    Description mechanical marks

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

    Physical characteristics

    Temperature Е, HPa r, kg/m3 l, W/(m · °C) С, J/(kg · °C)
    20 90-110 7200 50 500

    A description of the physical symbols

    Name Description
    Е The normal elasticity modulus
    l Coefficient of thermal conductivity

    Technological properties

    Name The value
    Microstructure Perlite or pearlitic-ferritic. Graphite plate, small and medium.