General Knowledge of Hot Forging
Hot forging is a forging process in which the material is heated to a recrystallization temperature of approximately 900°C to 1,200°C or higher, depending on the material, before being formed. For iron, the appropriate temperature for hot forging is about 1,100 to 1,250℃, and for brass, about 700 to 750℃.
The advantage of hot forging is that the metal material is heated to a high temperature, so the deformation resistance of the material is relatively low and large parts that would be difficult to form by cold forging can be processed. On the other hand, the disadvantage is that the accuracy, including dimensional tolerance and surface roughness, is inferior to cold forging due to the large dimensional change of the workpiece caused by temperature change. In addition, since annealing is required to remove internal stress (distortion), the cost of secondary processing can be a bottleneck.
The products manufactured by the process of hot forming are various many kind,like high pressure valve and pomp,cylinder, industrial machine parts. As we mentioned, the most of them are large parts comparatively.