Why should the mold warm up before forging
Because the mold is cool, the surface will be expanded with the contact with the high-temperature steel, and the core temperature will not expand. As a result, the surface will be pulled apart to form cracks. In addition, the forged steel is not good because the cold mold The contact temperature will drop rapidly, resulting in uneven temperature inside and outside the steel, uneven deformation and short forging time.