An innovative effort by a team of employees from the Steel Melting Shop-II (SMS-II) department of SAIL, Rourkela Steel Plant (RSP) has significantly enhanced safety and achieved substantial savings for the company.
It is worth mentioning here that, the team comprising Mr. Deepak Kumar Mohanty, MOMT, SMS-II (Electrical), Mr. Prashant Kumar Nayak, MOMT, SMS-II (Electrical) and Mr. Amulya Kumar Bisoyi, SOST, SMS-II (Mechanical) presented the project at the Hazard Analysis Competition-2024 organised by SAIL Safety Organisation, Ranchi to bag the 1st Prize. Notably RSP bagged the 1st Prize for the first time in the competition.
The theme of the project was ‘Enhancing Workmen Safety while Adjusting Skirt Limit Switch of Converter’ in the Basic Oxygen Furnace (BOF) Shop of SMS-II. It is noteworthy that a water cooled movable skirt attached at the bottom of Converter Hood, is raised or lowered by the by the operator at Control Room and is an essential interlock for the tilting of the LD Converter Vessel of BOF Shop.
Previously, the limit switch sending the signal for the skirt height was located inside the Cooled Hood Trolley, making maintenance extremely challenging due to the high surrounding temperature of around 70 degrees Celsius and unsafe conditions such as exposure to hazardous gases and the risk of falling metal skulls from the Converter Lance.
It is to be noted that any delay in addressing Skirt Interlock problem after Main Blow in Converter results in increased Tap to Tap time, production loss, temperature drop and deterioration in steel chemistry and critically a drastic reduction in converter lining life since re-blow is then required to get the end chemistry.
After extensive brainstorming, the team decided to reposition the limit switch to a safer location at the 21-meter level of the shop floor. They consulted heads of the Electrical, Mechanical, and Design departments and developed a protocol with the help of the department safety officer. Under the guidance of Mr. T.P. Sivasankar, CGM (SMS-II), the new modified system with pulley and counterweight mechanism was commissioned. Cables were laid from the site to the process computer room to carry the signal for process automation, which serves as an interlock for LD-converter operations during steelmaking.
The relocated skirt limit switch now enables maintenance crews to adjust it safely within the stipulated time. The project has ensured tangible benefits of approximately Rs. 1.28 Crore savings per year.
