Induction Hardening Application

Introduction of Induction Hardening

Induction hardening is an advanced surface heat treatment technology widely used to improve the surface hardness and wear resistance of metal workpieces. This process utilizes the principle of electromagnetic induction to generate high-frequency eddy currents on the surface of the workpiece, rapidly heating the surface to the hardening temperature. Depending on the required depth of the hardened layer, different frequencies of current can be selected.

The main advantages of induction hardening include:

1. Efficient heating: Due to the direct action of the heat source on the surface of the workpiece, the heating speed is fast, the thermal efficiency is high, and there is less oxidation and decarburization of the workpiece surface.

2. High surface hardness: After hardening, the surface hardness of the workpiece is significantly increased, while the core maintains good plasticity and toughness, and the impact toughness, fatigue strength, and wear resistance are all enhanced.

3. Minimal deformation: Only the surface is heated, resulting in minimal overall deformation of the workpiece, making it suitable for the treatment of precision parts.

4. Easy to control: The depth and hardness of the surface hardened layer can be precisely controlled by adjusting the current frequency and power.

5. Strong adaptability: Suitable for various shapes and sizes of workpieces, including gears, shafts, crankshafts, camshafts, and rolls.

The equipment mainly consists of an induction power supply, load line, capacitors, transformers, inductors, and hardening machines. The power supply equipment outputs an alternating current with a suitable frequency, and the inductor is designed and manufactured according to the shape and requirements of the workpiece to ensure uniform heating.

Overall, induction hardening is an efficient, energy-saving, and environmentally friendly heat treatment method. By precisely controlling the process parameters, it can significantly enhance the performance of the workpieces and is widely used in fields such as automotive, aviation, and machinery manufacturing.

Concrete pump tube automatic hardening production line

1）Configuration Overview

1. XZZ-250SCN DSP digital High frequency induction heating machine

2. KCZG-WS-3000 Induction hardening machine for conveying straight pipe

3. Industrial Chiller–Hardening fluid and power cooling

4. Plate heat exchanger and  stainless steel tank with 2m³ water tank and contains 1.5KW water pump.

2）Hardening Process Flow

Using 250KW IGBT digital intelligent DSP induction heating machine, frequency 5-20khz.  pipe hardening 250kW Induction heating power output is used to quench the inner wall, and the inner water spray is used to quench the inner wall. According to the process demand, DSP power supply can be used for digital power distribution. When the induction heating equipment is heating the pump pipe of different specifications, the output power of inductor can be set automatically according to the model of the workpiece and the control system of the machine tool.

The central control center has a variety of heating process implementation and automatic control program switching functions. No manual intervention is needed to switch between different quenching processes.

The induction hardening heating coil is equipped with a water spraying device. Through the centralized control center program switching, the water spraying cooling process is implemented automatically for different workpiece models；

The running speed of the straight pipe of the production line is controlled by a fast high-power servo motor. The designed air running speed is ≥3 m /min. When heating, the rotating speed is controlled by frequency conversion motor, supported by multistage supporting roller in the middle of straight pipe, which can meet the requirements of working procedure (including feeding and unloading): 6min/ pc (3 meters), no soft belt, no thread.

Main technical parameters of quenching machine tool