What is the significance of the temperature control of the intermediate frequency furnace in the billet heating production?
Reasonable control of the heating temperature is beneficial to increase the output and quality of rolling, and reduce the energy consumption and wear of the intermediate frequency furnace. At the same time, the best plasticity is obtained, and the smallest resistance to deformation is obtained
What is the significance of reasonably controlling the heating speed of the intermediate frequency furnace? The heating rate of steel refers to the degree of increase in surface temperature per unit time when the steel is heated, and the unit is ℃/h. In the production of rigid billet heating, due to improper control of the heating speed, the temperature difference between the inside and outside of the steel is too large, and large thermal stress is generated inside the steel, which causes cracks or tears in the steel. The higher the heating rate, the higher the unit productivity of the intermediate frequency furnace. The less oxidation and decarburization of the billet, the lower the unit combustion consumption. Therefore, rapid heating is an important measure to improve various indicators of the intermediate frequency furnace.
How to reasonably control the heating temperature?
1. At the initial stage of heating, the heating rate should be limited reasonably. Because the faster the heating rate, the greater the temperature difference between the surface and the center, and the greater the temperature stress, which may exceed the strength limit of the steel and cause the billet to crack.
2. When the temperature of mild steel is 500~600℃, the influence of temperature stress can be ignored. For metals with high plasticity, temperature stress can only cause plastic deformation, which is not harmful.
3. The heating rate should fully consider the physical properties, geometry and size of the metal. For thin materials, the heating speed can be adjusted arbitrarily, but for large high-carbon steel and alloy steel, the heating speed should be carefully adjusted.
How to correctly understand the heating time of the intermediate frequency furnace in the heating of just billet?
The heating time of steel refers to the minimum time necessary for the billet to be heated in the furnace to the temperature required for rolling. The heating time includes three stages of billet preheating, heating and soaking.
How to correctly calculate the heating time of the billet?
The heating time of the billet needs to be affected by many factors. In production practice, the following formula is often used to heat the billet in a continuous heating furnace:
τ=CS
Where τ——heating time, h
S——thickness of steel material, cm
C——The time required for heating per centimeter of steel material, h/cm
For low carbon steel C=0.1~0.15
For medium carbon steel and low and medium alloy steel C=0.15~0.2
For high carbon steel and high alloy steel C=0.2~0.3
For advanced tool steel C=0.3~0.4
