Steel Bar Rolling Process 1

With the advancement of modern technology, an increasing number of steel manufacturers are adopting advanced processes to improve product quality and enhance plant efficiency. In steel bar production lines, the following processes are commonly used:

1. Direct Rolling of Billets

Direct rolling technology is suitable for producing plain carbon steel and low-alloy steel. This process can be categorized into three typical configurations:

1. Combination Heating: Both a conventional heating furnace and induction heating are used.
2. Induction Heating Only: No conventional furnace is used; instead, induction heaters reheat continuous casting billets.
3. No Reheating: The billet is sent directly from the caster to the rolling mill without any heating.

In the configuration without a conventional furnace between the continuous casting machine (CCM) and the rolling mill, induction heaters alone are used to raise the billet temperature. This setup demands precise coordination between steelmaking and rolling capacities, making production organization more complex.

In cases where neither conventional nor induction heating is applied, billets are directly rolled. To facilitate this, the billet cutting point should be aligned with the critical solidification point, pushing the conventional cutting position forward and increasing the billet’s inherent temperature. After cut-to-length, the billet should reach the rolling mill within 2 minutes, and the temperature drop should not exceed 50 °C. If the roller table is particularly long, thermal insulation covers can be used to maintain billet temperatures. The average billet temperature at the mill entrance should reach 1000–1050 °C to meet rolling requirements.

2.Headless Rolling Process

Rectangular billet or square billet through multiple continuous rolling, into the rectangular section of the middle plate, after four racks of multi-line slitting rolling and cooling, to get the finished threaded steel bar. The other method is single line high speed headless rolling bar or wire. This process has the following advantages.

This process involves feeding rectangular or square billets through multiple continuous rolling stands to form a rectangular-section intermediate plate. After passing through four slitting stands and cooling, the finished threaded steel bar is produced. Alternatively, high-speed single-line headless rolling can be used for bars or wires. The headless rolling process offers several advantages:

1. Increased Coil Weight and Output: Eliminating the momentary speed reduction during billet biting results in stable continuous rolling and reduced tension fluctuation, allowing for higher rolling speeds.
2. Higher Utilization and Capacity: With no time gap between consecutive billets, and no need for head and tail cutting or trimming, mill utilization increases by over 3%, and production capacity rises by 2–5%. Coil weight can also be flexibly adjusted via flying shears.
3. Reduced Wear and Costs: Fewer impacts on rollers and guides from rolling low-temperature billets leads to reduced maintenance and lower component costs.