NLMK Introduces Digital Service to Boost HSM Performance

NLMK Group’s flagship production facility NLMK Lipetsk, a Metal-Expo regular exhibitor has introduced a digital service to optimize the slab rolling rate at its hot strip mill.

The mill rolls slabs into 1.5–16 mm thick hot-rolled strips. Slabs are preheated in five furnaces before being delivered to the rolling mill one after the other, as directed by the operator. When selecting the rolling rate, the operator is guided by a number of factors, aiming to prevent slab collisions, to ensure the required temperature level in certain areas depending on the steel grade, and to maximize mill performance. Previously, the operator would calculate the slab discharge rate manually, having to rely on their intuition and experience.

The new digital system determines the rate automatically. A machine learning-based model analyses slab dimensions, composition, and heating level, as well as the required finished product parameters and the condition of the mill. The model processes this data to determine how long it should take a slab to travel from the furnace to the rolling mill, and prompts the operator to discharge the next slab from the furnace.

The project was launched at the end of last year. The digital system has already enabled a 5% reduction in the the slab discharge interval, thus boosting hot strip mill productivity. Company experts continue to train the model to further increase its efficiency.