What is the principle of high frequency induction heating equipment?

High-frequency induction heating equipment refers to the equipment that performs surface quenching on the workpiece, which belongs to the metal heat treatment method, so what is the principle of high-frequency induction heating equipment?

The workpiece is placed in the inductor. The induction heating equipment is generally a hollow copper tube. The medium frequency or high frequency alternating current (1000-300000Hz or higher) is applied. The alternating magnetic field generates an induced current of the same frequency in the workpiece. The induced current is unevenly distributed in the workpiece, with strong surface, weak inside and close to zero center. By using this skin effect, the surface of the workpiece can be rapidly heated and the surface temperature will rise to 800-1000 in a few seconds, and the temperature in the center rises very little.

Scope of application:

1. Welding of carbide saw blade size teeth.

2. Welding and annealing of spectacle frames and parts.

3. Thin wires of jewelry heads, thin parts of various electronic components, welding and silver welding).

5. Mechanical and electrical industry (fine metal joints silver copper welding micro-motor shaft and other quenching and tempering).

6. Wire industry (fine wire strip annealing).

7. Tool welding, paper cutter, shoe blade quenching.

8. Toy industry (rolled thin metal sheet tempering).

How to choose medium frequency induction heating equipment

Intermediate frequency induction heating equipment is often used in the forging industry, casting industry and heat treatment industry, especially in automobile manufacturing, construction machinery, machine tool manufacturing, heavy machinery, bearing industry, railway transportation and other industries. How should we make a choice?

1) The shape and size of the workpiece to be heated: the workpiece is large, strip-shaped, solid, and induction heating equipment with high relative power and low frequency should be selected.

2) For small workpieces, pipes, plates, gears, etc., select induction heating equipment with low relative power and high frequency.

3) Heating depth and area: large heating depth and area, overall heating, high-power low-frequency induction heating equipment should be used; shallow heating depth, small area, local heating, selection of relatively low power, high frequency induction heating equipment, the required heating speed requires fast heating speed, so induction heating equipment with relatively high power and frequency should be selected.

4) Equipment continuous working time: continuous working time is long, relatively choose induction heating equipment with slightly higher power.

5) The connection distance between the induction element and the equipment: the connection is long, and even water-cooled cables are required for connection, so induction heating equipment with higher power should be selected.

6) Process requirements: Generally speaking, quenching and other processes can choose lower power and higher frequency; annealing, tempering and other processes, the relative power is higher, the frequency is lower, such as red stamping, hot forging, smelting, etc., need to diathermy effect is good process, the power should be larger, the frequency should be lower.

7) Material of the workpiece: In metal materials, the relative power with high melting point is large, and the relative power with low melting point is small; low resistivity uses more power, and high resistivity uses less power.