When the rated power of the induction heating furnace is not enough, how to inductively heat a super large workpiece?
When the rated power of the induction heating furnace is not enough, the super large workpiece can be induction heated by the following methods:
1. Add magnets to improve the efficiency of the inductor. For example: the diameter of the roll is large, and the power of the intermediate frequency power supply used is not enough. Later, a silicon steel sheet conductive magnet was installed on the roll inductor to improve the efficiency of the inductor and solve this problem. Originally, it was generally believed that the addition of a permeable magnet to the outer circle inductor had little effect. In fact, after the addition of a permeable magnet to the outer circle inductor, the escape of magnetic lines of force is reduced and concentrated in the heating zone, and the efficiency can be greatly improved.
2. The workpiece is preheated in the resistance furnace before induction hardening. Before induction hardening of transmission gears was realized in a tractor factory in Romania, the gears were preheated to 40°C in a resistance furnace and then subjected to induction hardening. A company in the United States also used a similar process.
3. Preheat 1-2 times with induction heating, and then perform induction hardening. For example: 60kW intermediate frequency power supply, scanning quenching Φ100mm left and right shaft parts, the shaft parts are preheated 122 times, and then scanning and quenching, which solves the heat treatment problem of machine repair parts. Scanning and quenching of the inner bore of the cylinder liner also adopts this process. When the cylinder liner rises, it scans for preheating, and then the cylinder liner descends for scanning quenching.
