The furnace is suitable for continuous dewaxing, drying and roasting heat treatment of medium and small precision casting models. The furnace lining is a composite structure (heavy acid-resistant high-alumina brick and aluminum silicate fiber cotton). The furnace side is equipped with a special burner for gas. There is waste heat recovery device for preheating combustion air. The equipment has a high degree of automation, low energy consumption, reliable operation and stable product quality.