CELSA Barcelona and SMS group have successfully completed the upgrade of the medium section mill at CELSA’s Castellbisbal site in Spain. Commissioned in 2001 by SMS group, the mill has played a central role in producing high-quality long products such as beams, angles, and channels for the construction industry. The revamp covers the replacement of one of the 25-year-old first-generation CCS^® (compact cartridge stand) mill stands in the tandem rolling group, aimed at providing higher rolling forces. In addition, the revamp included the installation of upgraded electrical and automation equipment, featuring new and advanced control functions. From contract signing to the start of erection, the project was completed in just 12 months (in the same year) during the annual planned maintenance shutdown. 

In late 2025, CELSA Barcelona partnered with SMS to modernize its medium section mill. The new and latest generation of CCS^® mill stand was fully assembled and tested at the SMS workshop to verify all its functions and interfaces before being installed on site. Following comprehensive testing, SMS’s mechanical and automation experts integrated the new equipment into CELSA’s medium section mill. The existing Gen-1 CCS^® (UR) stand was replaced by the new and latest-generation CCS^® (UR) stand, featuring innovative design improvements and functionalities that boost the competitiveness of the plant. 

The modernization included an upgrade of the technological control system (TCS), whereby the legacy VME system was replaced with discrete sensor/actor cabling to a PC-based (APC) Probas platform. A complete Profinet network migration creates a unified hardware software ecosystem with high-speed communication, requiring 90 percent less cabling. The new TCS comes with the latest package of features to improve the rolling process, including optimized calibration sequence, improved accuracy, enhanced processing stability, and advanced maintenance support.

Hot commissioning was completed two days ahead of schedule. The very first start-up beam was produced within the desired tolerances, followed by a successful 700-ton rolling campaign during the night shift and resumption of regular production the following day.

Since its original commissioning in 2001, the medium section mill at the Castellbisbal site has undergone continuous optimization. Originally rated at 500,000 tons per year, the plant’s capacity has been increased to approximately one million tons per year over the course of previous upgrades, including a higher-capacity cooling bed and advanced CRS^® (compact roller straightener), enabling it to process heavier products. The current modernization further strengthens CELSA Barcelona’s capability to produce high-quality long products for the construction sector. 

SMS’s extensive expertise and CELSA’s close collaboration laid the foundation for the successful completion of the revamp in record time. This success has also solidified SMS’s partnership with CELSA Barcelona.