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 |
| The 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 from ferrous metals and alloys cast and connecting parts to them | В61 | GOST 5525-88, GOST 9583-75 |
| Castings of cast iron (gray 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 | The 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.).
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 characteristics
| σB, MPa | Brinell hardness number, 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 |
|---|---|
| σB | Limit short-term strength |
