The mandrel bar is inserted into the solid steel billet and penetrates through it to form a hollow shell.
During piercing, the billet is rolled by a set of rolls positioned at 60° to each other.
This process forms the hollow shell into the designed outer diameter and specified wall thickness.
The mandrel bar is then separated from the finished tube by a stripper unit.
To enable smooth stripping, a non-metallic coating is applied to the mandrel surface.
Before re-entering the rolling cycle, special separators and lubricants are applied to the mandrel bar.
Throughout the rolling operation, the mandrel and rolls work in coordination to reduce and evenly control the wall thickness of the seamless steel tube.
Piercing Mill
Piercing Mandrel
The mandrel bar is inserted into the solid steel billet and penetrates through it to form a hollow shell.
| Product Type | Elongated cylindrical tool for tube deformation |
|---|---|
| Function | Penetrates steel billet to form hollow cavity; core tool in tube deformation zone |
| Key Material Properties | High hardness, excellent wear resistance |
| Performance Features | High temperature resistance, exceptional wear resistance |
| Dimensional Precision | Precise diameter, excellent straightness, high concentricity |
| Surface Quality | Smooth finished surface |
