Nodular Pearlitic Cast Iron Rolls, also known as SGP rolls, are composed of nodular graphite and carbides distributed in a pearlitic matrix. Their properties are similar to indefinite chilled cast iron rolls, while the graphite structure changes from flake graphite to spheroidal graphite.
Compared with indefinite chilled rolls, pearlitic rolls generally provide higher strength and reliable performance under rolling conditions. These rolls can be produced by static casting, or by centrifugal double-pour casting according to different mill requirements.
Chemical Composition
| Symbol | C | Si | Mn | Cr | Ni | Mo | Mg |
| SGP I | 2.90-3.60 | 1.40-2.20 | 0.40-1.00 | 0.10-0.60 | 1.50-2.00 | 0.20-0.80 | ≥0.04 |
| SGP II | 2.90-3.60 | 1.20-2.00 | 0.40-1.00 | 0.20-1.00 | 2.01-2.50 | 0.20-0.80 | ≥0.04 |
| SGPIII | 2.90-3.60 | 1.00-2.00 | 0.40-1.00 | 0.20-1.20 | 2.51-3.00 | 0.20-0.80 | ≥0.04 |
Physical Properties
| Symbol | Barrel Hardness | Roll Neck Hardness | Tensile Strength △ |
| SGP I | 45-55 HS | 35-55 HS | ≥350/450 MPa |
| SGP II | 55-65 HS | 35-55 HS | ≥350/450 MPa |
| SGPIII | 62-72 HS | 35-55 HS | ≥350/450 MPa |
Recommended Applications
- Rolls for roughing stands of medium section mills, bar mills, and wire mills.
- Rolls for intermediate and finishing stands of bar mills.
- Rolls for sleeves of universal stands.
Product Features
- Nodular graphite structure with a stable pearlitic matrix.
- Higher strength compared with indefinite chilled cast iron rolls.
- Good performance for roughing, intermediate, and finishing applications.
- Available by static casting or centrifugal double-pour casting methods.