Technology for gunning gas ducts of heat generating units with combined refractory lining

Abstract

The heat-generating units’ gas duct refractory lining specifics are their design assuming different temperatures and speeds of air and gas flows in different parts. Accordingly, the heat-insulating wear is not uniform along the entire gas duct length. This entails the gas duct repair and restoration issue. Combined linings are often required. Modern approaches to thermal insulation allow repairs under complicated conditions without long-term interruption of production processes. Technologies for lining gas ducts with refractory materials by gunning are promising. In the study, general scientific methods were used: analysis, synthesis, comparisons, generalization, etc. The gunning experiment allowed studying the features of materials and technologies in practice. The study object was the heat-insulating coating technology. The study subject was sintering machine gas duct lining by gunning. We have found effective process parameters of creating the heat-insulating coating by gunning. The gas duct lining scheme has been developed and tested, ensuring the design wear and corrosion resistance. An experimental dependence of wear and corrosion resistance on the material and process parameters of the gunning mix application and composition has been obtained. Combined technologies for the manufacture of heat-insulating refractories allow solving several systemic problems such as reducing the cost, labor intensity, increasing the time between overhauls, and environmental issues.