A 14-year-old electric-arc- and refining-furnace PLC system covering 45 remote stations was suffering repeated communications dropouts. DUCHENG migrated the network backbone to a managed-switch and fiber-ring PROFINET architecture, completing installation, commissioning and return to production in an accelerated maintenance window.
The automation system for electric-arc furnace No. 2 at Shagang's EAF plant was widely distributed: 22 remote stations for the EAF PLC system and 23 for the refining-furnace PLC system. After 14 years of operation, long communications runs and the site's interference environment contributed to repeated network interruptions and dropped stations, affecting production stability and safety.
From field testing to a new network architecture
DUCHENG automation engineers inspected the equipment, tested communications and confirmed the upgrade boundary with the client. The selected design moved the main network from PROFIBUS to PROFINET, added managed industrial switches, replaced the relevant distributed interface modules and introduced a fiber ring for a clearer, manageable structure across the dispersed stations.
Delivering after the schedule moved forward
The work had originally been planned for the second half of 2022, but the implementation window was brought forward to December 2021. The team ran equipment coordination, installation and cabling, program checks and network testing in parallel, then completed construction and commissioning inside the maintenance window.
The outcome
The upgraded communications system entered service and furnace No. 2 returned to production. The project provides a practical path for aging distributed PLC networks: establish a field communications baseline first, then address topology, interface modules, switching and fiber redundancy as one engineered system.
The original WeChat text contains the typo “PROFINE.” This website draft corrects it to PROFINET based on the project topology image and equipment context; the project technical owner must still approve the correction before publication. Industrial-network upgrades require site diagnosis, shutdown planning and full testing.
