Induction heating has a unit power of up to 500-1000kW per square meter (high magnetic flux density and a certain amount of effective heating layer depth can be established in the blank) and short diathermy time (due to the heat coming from the blank itself), which brings the following benefits to the heating of the forged blank:
1) The heating speed is fast, and the oxidation and decarburization on the surface of the soil billet are also very small. It can make the soil billet obtain higher fatigue performance. The oxide content is 3%-4% when heated by flame, while induction heating can be controlled at 0.05%-0.5%. Induction heating has no fuel products in the heating area, so relatively clean blank can be obtained, which is a very beneficial factor for the high-quality manufacturing of blank.
2) Short heating time is conducive to local heating. The temperature in the heating zone can be established quickly, and the temperature excess zone is relatively narrow, which reduces the loss of electrical energy and is conducive to the forging and pressing of some local heating parts.
3) Energy saving and material saving
4) Short heating time makes induction heating easy to improve productivity and reduce production costs.
5) The heating speed is fast, the heating time is short, and the austenite grains obtained are fine. The workpiece heated by induction has a very good metallographic structure.
6) The device starts quickly. There are many refractories in the flame furnace, starting to absorb a lot of heat, that is, the heat loss of the device is large, it must be maintained at a certain temperature when not working.
7) Fast heating speed, less oxide skin, so that the life of the mold can be extended (some data show that only one less oxide skin caused by induction heating can increase the life of the mold by 30%)
8) The induction heating method can effectively prevent the blank from insufficient heating temperature or overburning under specific power and beat, and fundamentally guarantee the forging quality.
9) Due to the compact equipment and adjustable power, induction heating can form a production line with forging and pressing equipment to achieve synchronization.
From the above mentioned, induction heating is an ideal means of heating billet, especially for a relatively single batch of billet.