Dummy Bar Head
Dummy bar head for continuous casting is the core component of the dummy bar in direct contact with the copper mold assembly, and its parameter design directly affects the success rate of continuous casting, the initial solidification quality of the billet and the reliability of disengagement.
Main Functions
- Lead the billet: During the continuous casting process, molten steel is poured into the copper mold, and with the vibration and cooling of the copper mold, the steel gradually solidifies into a billet. dummy bar head is located underneath the copper mold, and it is responsible for leading and supporting the billet that has initially solidified, and ensuring that it enters into the secondary cooling zone without any problem.
- Control of billet shape: The design and shape of the dummy bar head has a direct influence on the shape and quality of the billet. A proper design of the dummy bar head can help control the cooling rate and shape of the billet, thus improving the quality and yield of the billet.
Principle of operation
The working principle of the dummy bar head is closely related to the overall workflow of the continuous casting machine. During the continuous casting process, molten steel is first poured into the copper mold, and as the copper mold vibrates, the steel begins to solidify. At this point, the dummy bar head is located underneath the copper mold and is closely connected to the initially solidified billet. As the billet grows, the dummy bar head pulls the billet down through the secondary cooling zone and finally to the cutting zone. Throughout the process, the Dummy bar head not only provides traction for the downward movement of the billet, but also helps to control the shape of the billet and the cooling rate through its special design.
Reference parameters:
- Structural parameters
| parameter | Typical range / description | act on |
| Head shape | Swallowtail, rectangular, cone (adapted to different crystallization bottom shapes) | Ensure to with the crystallization seal to prevent steel leakage |
| sectional dimension | -Billet / rectangular billet: 200200mm ~ 600600mm
-Slab: width 1000~2500mm, thickness 150~400mm |
Match the casting section to ensure the initial solidification uniformity |
| length | 300~800mm (related to crystallization length and drawing speed) | Provide sufficient guide distance to stabilize the shell formation |
| Tone Angle | 1°~3° (commonly used) | It is easy to separate from the casting billet and reduce adhesion |
| Size of the graphite inlay block | The thickness is 20~50mm, and the width accounts for 60%~80% of the head width | Reduce the friction coefficient with the high temperature casting to prevent adhesion |
- Selection parameters
| Type of cast billet | Recommended head parameters |
| Small section square blank | Head size 200200mm, material 42 CrMo + Al ₂ O ₃ coating, cooling water flow rate 5m³ / h |
| Large section slab | Head width of 2000mm, material H13 + WC coating, cooling water matrix channel design, water flow of 15m³ / h |
3.Maintenance parameters
| parameter | Maintenance standards |
| Graphite block wear | Replacement for thickness <10mm (50~200 times) |
| Coating peeling area | > 10% surface area |
| Bolt pretension attenuation | Monthly testing with torque wrench, attenuation> 15% requires retightening |
| Cooling water channel scaling | Annual pickling and scaling (treated immediately when flow rate drops> 20%) |
Our company has many years of experience in the production and marketing of dummy bar heads, with professional technical personnel, according to the individual needs of customers, production and processing. The above parameter data can be used for reference, if you have specific needs, please feel free to contact us