Common problems and countermeasures in the high-frequency hardening process of gear ring

Gear ring high-frequency hardening equipment is a special equipment for hardening the gear ring. When quenching is carried out by induction hardening along the tooth groove, the common frequency is 1-30kHz, and the gap between the inductor and the part is controlled at 0.5-1mm. It is necessary to precisely control the sensor to be very symmetrical with the adjacent two tooth sides, and strictly control the gap between the tooth side and the tooth root.

Common problems and countermeasures in the high-frequency hardening process of gear ring (here mainly take the induction hardening method along the tooth groove as an example)

1. The hardened layer is unevenly distributed, one side has high hardness and deep hard layer, and the other side has low hardness and shallow hard layer. This is because the induction hardening along the tooth groove has high position sensitivity compared with the rotary induction hardening of the ring inductor. It is necessary to design and manufacture a high-precision positioning device to ensure a highly symmetrical distribution of the gap between the tooth side and the inductor. If it is not symmetrical, it may also cause the short-circuit and arcing of the sensor and the parts on the side with a small gap, which may damage the sensor early.
2. Annealing of hardened tooth side. The reason is that the auxiliary cooling device is not adjusted in place or the amount of coolant is insufficient.
3. The copper tube at the tip of the sensor is overheated. When using the non-embedded scan quenching process along the tooth groove, because the gap between the inductor and the part is relatively small, the heat radiation of the heating surface and the limited size of the nose copper tube make the copper tube easy to overheat and burn out. , So that the sensor is damaged. Therefore, the sensor must ensure that there is sufficient flow and pressure of the cooling medium to pass.
4. The shape and position of the ring gear change during the sensing process. When scanning and quenching along the tooth groove, the processed tooth will swell by 0.1～0.3mm. Deformation, thermal expansion, and improper adjustment of the sensor can cause damage to the parts and the sensor due to collision. Therefore, the thermal expansion factor should be considered when determining the gap between the inductor and the tooth side, and an appropriate limit device should be used to ensure the gap.
5. The performance of the inductor's magnetism is degraded. The working conditions of the magnetic conductor are bad, and under the environment of high-density magnetic field and high current, it is very easy to be damaged by overheating. At the same time, quenching medium and corrosion will make its performance degraded. Therefore, the daily maintenance and maintenance of the sensor must be done well.