Reclamation of Rack Teeth of Tilting Mechanism of Mixer of Steel Melting Shop of Bhilai Steel Plant

Abstract

Reclamation, in general, means economical sense of unused damaged waste item by value addition which otherwise would have been useless. Reclamation is the process of reclaiming some thing from loss or from a less useful condition. Economics plays a very important role in deciding to go for reclamation.

Bhilai Steel Plant is an integrated steel plant. In this plant, the production of steel is done through two routes, first one is the conventional route (ingot route) and second route is converter and continuous cast route.

The main function of Mixer in any steel melting shop is to receive hot metal (pig iron) from Blast Furnace and to supply hot metal to the Twin Hearth Furnace or Converters. The Mixer acts as a reservoir for homogenization of chemical composition and temperature of hot metal received from different Blast Furnaces.

For pouring of hot metal in to the ladle, the Mixer is tilted towards ladle. After filling one ladle, the Mixer is then tilted back for positioning of next empty ladle. So, for pouring of each ladle. Mixer is to be tilted to and fro. Hence tilting mechanism is very vital equipment of Mixer.

While inspecting, it was found that the rack teeth of tilting mechanism is worn out beyond permissible limit and it was unsafe to work i.e. tilting of Mixer for handling of hot metal. At that time, the spare rack was not available. Hence it was decided to reclaim the other rejected rack which was lying.

The estimated value of Mixer Rack is around Rs. 1.75 crores.

This paper deals with the reclamation technology adopted to revive this vital assembly. This paper includes selection of welding consumable, welding parameters, preparation, preheat and post heat treatment and precautions for entire reclamation procedure.