The blast furnace is composed of furnace foundation,furnace bottom,furnace hearth,furnace body,furnace top(including feeding device),furnace holder,blower system,water-cooling or evaporated cooling system,melt release device and external crucible.

The furnace foundation it is builded by concrete or reinforced concrete,we can set up steel support or jack,used to support the furnace bottom. 　　　

The furnace bottom the bottom is cast steel plate or cast iron plate,followed on the plate are asbestos sheet,clay brick and magnesite brick. 　　　

The furnace hearth made of water jacket wall(or build magnesite brick),we also can called it internal crucible. 　　　

The furnace body made of some water jackets,each water jacket 0.8~1.2m wide,1.6~5m high,welded by boiler plate,fixed on the special holder,wind and water pipes are also arranged on the holder.