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What kind of heat treatment can the high frequency induction hardening machine perform on the coil spring?

What kind of heat treatment can the high frequency induction hardening machine perform on the coil spring?

1. Bar heating is generally carried out by a high-frequency quenching machine with automatic feeding and discharging. The diameter of the material can reach 60mm and the length does not exceed 8m. The heating temperature of the steel bar is generally 880-950°C.

2. Coiling, using a computer-controlled core or coreless hot coiling machine, the processing material diameter is 20-60mm, and the heated bar material is hot rolled into a compressed coil spring of the required specification. The temperature of the spring after hot coil forming should be above 840°C, which is convenient for direct quenching. That is, quenched into 50-80 ℃ oil. The temperature of the spring oil outlet pool should be controlled within the range of 120-180°C to prevent its deformation and reduce the quenching stress. After quenching by high-frequency induction hardening machine, the hardness of the spring is greater than 54HRC.

3.Tempering. The quenched spring must be tempered within 2 hours to prevent quenching cracks. The tempering furnace is controlled by PLD, so that the tempering temperature is controlled within ±3°C, and the tempering temperature is 400-450°C. After tempering, the hardness of the spring can reach 45-50HRC. Springs that are prone to deformation during heat treatment are treated separately, and the shaping process should generally be added.