The waste heat treatment of large forgings uses its own heat to directly heat the forgings after forging, that is, the waste heat treatment of forgings omits the process of reheating the forgings before post-forging heat treatment, and the waste heat treatment generally has the following ways.

1, after forging, waste heat homogenization heat treatment. The forgings are directly sent to the heat treatment furnace after forming, still according to the conventional heat treatment process, the temperature of different parts of the forgings after homogenization, can shorten the holding time, this method is called waste heat homogenization heat treatment. For the shape of complex, is a large cross-section change forgings using the process can be forged quality stability.
2, Direct waste heat treatment after forging. After forging is formed, the waste heat of forging is used for heat treatment directly, and the forging and heat treatment are closely combined together, which saves a lot of energy waste caused by reheating of common heat treatment.
3, after forging, use part of the waste heat for heat treatment. The forgings are cooled to about 600 ~ 650℃ after forming, and then the forgings are reheated to the required temperature for heat treatment. This method can be refined to grain size, and save the energy consumption of heating forgings from room temperature to 600 ~ 650℃, generally suitable for forgings with high grain size requirements. A large number of application examples show that the microstructure and properties of the forgings after waste heat treatment reach the level of common heat treatment and have good process stability and reproducibility by reasonably controlling the cooling parameters after forming. Using waste heat for heat treatment eliminates heating process, saves energy, and costs investment and maintenance of heat treatment equipment. Forging industry is a major energy consumer, and the heat treatment of forgings is a major energy consumer in forging production, accounting for about 30% ~ 35% of the total energy consumption of the whole forging production. Forgings energy consumption accounts for about 8% ~ 10% of forgings cost, energy consumption can not forgings production cost, economic benefits of enterprises, and the energy problem is related to a sustainable development of the problem, to is related to the survival of the major problem. Therefore, the use of forging waste heat for heat treatment, energy saving, efficiency and other aspects are obvious, not only save energy, shorten the process, but also protect the environment.