13.5% fewer stand changes per month in a mini-mill’s section rolling

−13.5%

in stand changes per month in section rolling, in operation (four-month average)

12.2%

of billets hot charged in a real 15-day scenario, even as the last priority in the plan

≈ 5 min

to generate the monthly steel shop schedule in a real scenario

In the mini-mill, the steel shop melts scrap in an electric furnace and supplies rolling mills with billets of two sizes, at a faster pace than rolling. Only one line accepts hot billets, and the objectives conflict:

• Due date vs. energy. Casting early secures the due date, but the billet cools and reheating burns more gas.
• Productivity vs. quality. Long sequences yield more, but a diverse order book forces grade changes that generate scrapped or downgraded material.
• Rolling setup. With a fixed sequence of campaigns, stand changes did not follow the order book or inventories, and rolling hours were lost.

Until then, this balance depended on manual heuristics.

With Enacom’s Planning Digital Twin, the steel shop and rolling are now scheduled in a single plan, simulated before execution:

1. Plans campaigns and sequences

   defining the days for each billet size and grouping heats into sequences that respect the mill’s rules: sequence length, tundish changes, planned stops, and grade mixing.

2. Synchronizes the steel shop and rolling

   in an explicit order of priority: due date, stops, grade-change losses and, last, hot billets. The plan comes with KPIs and alerts for late demand or an idle steel shop.

3. Sequences section rolling dynamically

   grouping compatible sections and tracking inventories to avoid unnecessary stand changes.

The planner compares alternatives and decides. The monthly steel shop schedule is ready in about 5 minutes.

In section rolling, replacing the fixed sequence with dynamic sequencing reduced stand changes by 13.5% per month on average over four months of operation, with a peak of 29.5% in one of the months. Fewer stand changes mean more time rolling.

In the steel shop, the plan sent 12.2% of the volume to hot charging in a real 15-day scenario, even with hot billets as the last priority and only one line able to receive them, without getting ahead of due dates and stops in the order of priority.

• More time rolling. Fewer stand changes free up hours of section rolling for production.
• Energy in the plan. Hot billets enter as an explicit objective, used whenever the operation allows.
• Conflicts settled by rule. Due dates, stops, grade-change losses, and energy follow a defined order, not case-by-case decisions.
• Decisions made with the team, comparing alternatives in a solution that coexists with the ERP, MES, and APS already in use.

• Your electric steel shop supplies more than one rolling line, with different billet sizes and hot-charging capabilities.
• The order book has many grades, with mixing rules between them.
• Section rolling changes family, campaign, or roll frequently.

We start from your data: we customize the twin, validate the result in scenarios and a pilot, and only then scale. The results in this case reflect the conditions of that mill.