The 4-stand tandem cold rolling mill at SSAB Hämeenlinna produces coils with widths from 660 to 1,575 millimeters and thicknesses from 0.35 to 3.1 millimeters. In February 2023, Primetals Technologies received the final acceptance certificate (FAC) from the Hämeenlinna steelworks, a part of steel producer SSAB, for a comprehensive upgrade of the main drives for mill stand No. 1 at the tandem cold rolling mill in Hämeenlinna, Finland. SSAB Hämeenlinna manufactures premium products for customers in the automotive industry. These items include ultra-high strength galvanized steel, for example, for producing car safety components. The FAC marks the successful completion of Phase 1 of the modernization project. The second phase encompasses upgrading the main drives for mill stand No. 2.
Primetals Technologies upgraded the complete drive system, including transformers, drive, and motor, at mill stand No. 1. The project involved the manufacture of a synchronous motor that uses a new stator and a spare rotor, and slip rings. The old oil transformers were replaced with new, maintenance-free, environmentally friendly dry-type transformers. Also, the controllers and drive systems were upgraded to state-of-the-art technology—new excitation and auxiliary systems round off the Phase 1 scope.
The team from Primetals Technologies found a solution to merge the existing and new hardware and software systems successfully. The Level 1 automation system was modified and optimized to match the new environment as part of the solution.
Successful Past Projects
The upgrade secures the supply of spare parts for the mill stand drives and increases the availability of the tandem cold rolling mill. A key reason why Primetals Technologies initially won the order was the successful collaboration between SSAB Hämeenlinna and Primetals Technologies on several recent projects, including a modernization of the Level 2 automation system at the tandem cold rolling mill in 2022 and a modernization of the Level 1 automation system at the same mill in 2017.