Pig Iron / HP
Hematite Pig Iron
Pig iron type widely used in grey (lamellar graphite) cast iron production.
Technical Specifications
Key Features
- Medium-high silicon content (1.5-2.5% Si)
- Low sulfur ratio
- Promotes graphite formation
- Provides good machinability
- Controlled phosphorus level
Applications
- Grey (lamellar graphite) cast iron production
- Engine blocks and cylinder heads
- Brake discs and drums
- Machine beds
- Pipe and valve bodies
Dimension Table
| Element | Min. | Max. | Typical |
|---|---|---|---|
| C | 3.5 | 4.0 | 3.8 |
| Si | 1.5 | 2.5 | 2.0 |
| Mn | 0.5 | 1.0 | 0.7 |
| P | 0 | 0.08 | 0.06 |
| S | 0 | 0.03 | 0.02 |
Technical Notes
- 01High Si content supports graphite formation.
- 02P content should not exceed 0.08% (cold brittleness).
- 03Ideal charge material for lamellar graphite castings.
- 04Can be mixed with scrap for use.
Other Types
What is pig iron?
Pig iron is high-carbon crude iron (about 3.5–4.5% C) produced by reducing iron ore with coke in a blast furnace. It is brittle and not used directly; it is an intermediate product that is refined into steel (by lowering the carbon) or remelted into cast iron. Main types are basic (steelmaking) pig iron, foundry (hematite) pig iron and nodular pig iron for ductile-iron casting.
How pig iron is made and where it is used
In a blast furnace, iron ore, coke and limestone are charged in layers; the molten iron collects at the hearth and is cast as pig iron. Its high carbon and silicon content make it hard but brittle. In steelmaking (BOF/EAF) it is melted with scrap as the primary raw material for steel; in foundries it serves as a charge material to adjust chemistry for grey and ductile iron castings. Controlling the composition (C, Si, Mn, S, P) determines the quality of the final product.
Frequently Asked Questions
What is the difference between pig iron and cast iron?+
Pig iron is the raw intermediate from the blast furnace; cast iron is the finished product made by remelting pig iron and pouring it into moulds (grey, ductile, etc.).
What is the carbon content of pig iron?+
About 3.5–4.5% carbon, plus silicon, manganese, sulphur and phosphorus. This high carbon makes it brittle.
What is pig iron used for?+
As the primary raw material for steelmaking (together with scrap) and as a charge material in foundries for grey and ductile iron castings.
What is nodular pig iron?+
A special low-sulphur, controlled-composition pig iron suitable for producing ductile (spheroidal-graphite) iron castings.
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