Annealing and Coating Line (ACL) for Silicon Steel Strip

Tenova, with its over 40 years of experience, is one of the company with the competence and knowledge, of the entire process, which is required for the production of non-grain-oriented electrical steel strip.

Non-grain-oriented strip is annealed in a radiant tube furnace using a continuous process after cold rolling to ensure recrystallization and controlled grain growth. Top-quality steel requires strip temperatures above 1100°C and a very dry atmosphere with a high hydrogen content. This is followed by controlled cooling to obtain an extremely flat strip.

The Cleaning Section is a key process component to remove the residual Rolling oil and Iron Fines. This helps in minimizing the Furnace roll contamination and thus the frequency of pitting defect on the strip surface

The Tenova cleaning section is equipped with the special high efficiency electrolytic cleaning unit (HTMCD) properly combined with spray alkaline cleaning, high efficiency-quick maintenance brushing units to enhance the strip cleanliness and allowing to reduce of 20-25% the electrical consumption.

The next step is in-line coating with insulating varnishes of different qualities, through fully automatic roll coaters operating also in closed loop through the feedback of the in line coating gauge.

Then the varnish layer is dried and cured (or) hardened in a special drying furnace, which is generally fitted with a solvent post treatment system. The waste heat from the process is efficiently recovered and utilized for strip cleaning and drying.