Revamping of CSN BF2 hot blast stove no. 1

CSN BF no. 2 has only three hot blast stoves. Owing to the operational risks as well as output losses associated with the BF operation with just two hot blast stoves, the revamping time of this equipment becomes a crucial issue, requiring special attention in each phase of the project from planning to execution so as to shorten the time as much as possible. According to this context, the present paper describes in detail the main technologies used in the last revamping of hot blast stoves carried out in February 2007. These technologies included an accelerated cooling down curve, air conditioning system (good working condition) and convection heating system, which in association with an innovative construction methodology, involving movable and multilevel platforms, has allowed the project to be completed from blow to blow in a record time of just 67 days and 10 h, resulting in a reduction of costs around R$3·4m.