The Mechanical Shop of SAIL, Rourkela Steel Plant (RSP) has successfully revived a critical spare of Hot Strip Mill – 2 (HSM-2) bringing in huge savings for the company. The team showcasing exceptional expertise and innovation, used in-house resources to revive the drive spindle (F5-7), a high-value component worth Rs.3.5 Crores, that suffered a major breakdown on 24th November, 2024. The team salvaged the spindle and its connecting wobler entirely using in-house resources, avoiding prolonged downtime and production losses.
Notably, the failure involved sheared bolts stuck inside the wobler and damage to its internal threads, with the wobler seized tightly to the spindle. Despite the absence of spare parts, the Mechanical Shop team took on the challenging task of salvaging and restoring the critical equipment. Using advanced machines such as the Skoda Horizontal Boring Machine, CNC Plano Miller, CNC Milling, and Lathe Machines, the team meticulously carried out operations like scooping out broken bolts, repairing threads, and manufacturing new components.
The team fabricated a set of M58x3 threading taps and eight new M58x3 bolts, enabling them to re-thread the wobler and securely fasten it to the spindle. To reinforce the damaged threads, innovative stitching technology was employed by integrating a key that provided additional strength to the coupling between the wobler and spindle. After the reassembly, the bolts were fastened with a precise torque of 12.3 kNm, ensuring robust functionality.
On 30th November, 2024, the Mechanical Shop handed over the revived spindle to the user department. The spindle was reinstalled and has been performing flawlessly since then. This achievement highlights the Mechanical Shop’s exceptional problem-solving skills, technical expertise, and dedication to operational efficiency.
