Reducing production cost with Forever billet induction heating equipment
After discharging from CCM, billet surface temperature is 750-800 ℃, the center temperature can be up to 950-1000 ° C. The skin effect of one of induction heating fundamental effects is the gradual heating from the surface to the core. In fact, one-third of the billet does not need to increase the heat. Choose different frequency as per different billet size, then you can get the best heating power. Billet induction furnace heating technology guidelines include heating temperature, heating rate, heating time and heating standard.
In the early heating process, the billet surface produces a different temperature difference from the billet core. High surface temperature, large expansion, low core temperature, small expansion. But the surface and the core are a piece of metal, not just divided into two parts. Therefore, the surface will limit the core and give the core tensile stress. This stress is called “thermal stress” or “thermal stress.”
The heating speed of billet heating furnace is fast, so the temperature difference will be big from the surface to the core. When the temperature stress is at the elastic limit of the steel, it has no effect on the quality of the steel. With the temperature difference recuding and eliminating, the pressure will disappear. When the temperature stress exceeds the elastic limit of steel, the blank will have an impact on the plastic deformation. After eliminating the temperature difference, the stress will not be completely lost, that is residual stress. If the temperature stress exceeds the strength limit of steel, it will break during heating.
At this time, the temperature stress is more harmful to the middle of the billet. Due to the middle tensile stress, the general tensile strength of the steel is much lower than its compressive strength, so the middle temperature stress is easy to form an internal crack.
If steel is ductile, there is also a large surface and core temperature difference even during heating, which will only result in plastic deformation but no billet crack at any operating speed. If the thermal conductivity of steel is very good, the temperature difference between the surface and the core during heating is very small, so the plastic deformation or cracking caused by thermal stress during heating may be small.
Forever has much practical experience in designing and producing billet induction heating equipment, which can get uniform heating, make the temperature difference from the surface to the core the minimum, reducing customer’s production cost.
Contact person: Hailee Ma
Phone: 0086-18932783253(whatsapp, wechat)
Specialist of induction heating equipment and system in China; Glad to be your business partner in induction heating field.
Post time: 02-13-2018