Forgings factory for the basic requirements of furnace type is good heating quality, forging or forging heat treatment temperature requirements, uniform heating, less oxidation, burning loss and decarburization; Fast heating speed, can meet the production capacity, with high unit area productivity (bottom intensity); The furnace has high thermal efficiency, that is, low fuel consumption for heating metal per unit weight; Furnace structure is simple, compact, low cost, refractory materials and less consumption of various materials; Furnace life is long; Good working conditions, convenient operation and maintenance, as far as possible to achieve mechanization, automatic operation; Low noise, less harmful gas and smoke, its indicators should meet the requirements of environmental protection.
When the batch of products and the process are determined, the selection of furnace type becomes the key to realize the process to reduce energy consumption and production cost.
Furnace type directly affects fuel consumption, and the selection principle is as follows:
1. Production nature: Steel forging workshop should generally use push steel continuous heating furnace. Opening furnace, chamber furnace and through-through furnace can be used in forging workshop when heating medium and small forgings and small batch production. When heating large forgings, trolley furnace can be used. In the mass production of die forging workshop, according to the process requirements and the conditions of the enterprise itself, can choose to push rod furnace, circular furnace, stepping furnace and other continuous furnace.
2. Heating system: according to the process requirements of the heated workpiece, such as heating temperature range, heating uniformity, heating speed, furnace atmosphere requirements, whether the workpiece needs to preheat, the limit of oxidation and decarbonization degree and so on, and choose the appropriate furnace type.
3. Size of heating workpiece: push steel continuous furnace or trolley furnace can be used for heating large ingot; Opening furnace, mesh furnace or wall furnace can be used when the workpiece end is heated.
4. Waste heat utilization device: to save fuel and improve the thermal efficiency of the furnace. According to the process conditions, the continuous furnace with preheating section can be selected. In more cases, heat exchangers are selected. Some factories choose regenerative furnace.
The furnace length of continuous heating furnace has great influence on burnup consumption. When the workshop layout and billet condition permit, the furnace length should be extended appropriately to reduce the flue gas temperature of furnace tail and reduce heat loss.
5. Combustion device: adopt combustion device with high combustion efficiency to achieve effective heating. The choice of combustion device must pay attention to matching with the furnace plastic, to consider the conditions of the workshop.
6. Smoke exhaust: the furnace smoke exhaust is divided into two ways: upper and lower smoke exhaust. Choose according to the specific conditions of the region and workshop where the forgings factory is located.