A crucible furnace is one of the simplest smelting equipment, which is mainly used to melt non-ferrous metals with low melting points, such as copper, aluminum and their alloys. In this kind of furnace, the alloy is melted in the crucible, and the heat is transferred to the charge through the crucible, and the charge and the combustion product are not in direct contact, so the chemical composition of the alloy is almost Não afetado pelo gás do forno, e a temperatura do líquido da liga também é relativamente uniforme, que é sua principal vantagem . Suas desvantagens são menor eficiência térmica, alto consumo de combustível, menor capacidade de cadinho e más condições de trabalho .
When smelting, the metal is placed in a container called a crucible. The crucible is placed in the furnace and heated with diesel, heavy oil, gas or coke as fuel. Depending on the requirements, the crucible can be made of different materials such as graphite, refractory clay, cast iron, etc. There are several types of furnace bodies, such as pit Tipo, tipo fixo e tipo rotativo . Há também um forno de cadinho de resistência, que geralmente tem uma pequena capacidade e é usado principalmente em laboratórios .
The crucible furnace has a simple structure, small investment and fast production, and is widely used in the foundry workshops of small and medium-sized non-ferrous alloy processing plants and machine manufacturing plants. However, the crucible furnace has low heat utilization, small output, poor labor conditions, and is no longer suitable for large-scale production.
The crucible furnace has always been a device for smelting copper alloys. Nowadays, the proportion of crucible furnaces used for smelting copper alloys is very large. In ancient times, charcoal was used as the heat source for smelting, but now it is heavy oil, gas, electricity, and coke. Recently, in order to save energy and protect the Ambiente e, para melhorar a eficiência, algumas fontes de calor foram alteradas de óleo pesado para gás e alguns para fornos de indução .
The same trend is observed in crucible furnaces for smelting light alloys such as Al and Zn. Large-scale melting equipment has been converted to reverberatory furnaces, rotary furnaces, induction furnaces, etc., and small holding furnaces for small batch production or casting are still crucible furnaces. Due to the improvement of heating methods, the future development A tendência é o uso de óleo e gás limpos e leves; Pequenos fornos de retenção podem economizar energia por meio de forro de fibra de cerâmica e construção de parede de várias camadas .
