Selection of 1. induction heating equipment

The fluctuation range of output voltage shall be within 2.5%, the fluctuation of power shall be within 5%, and the action of instrument and relay shall be sensitive.Mixer truck raceway

Under normal circumstances, when the depth of the hardened layer is 0.5~2mm, the high frequency power supply above 10kHz should be selected; when the depth of the hardened layer is 1.0~4.0mm, the medium frequency power supply of 8~3 kHz should be selected; when the depth of the hardened layer is 10~20mm, the frequency power supply can be selected. In short, when the heated area or diameter of the workpiece is large, a lower frequency may be selected; conversely, for a heated product or a workpiece having a smaller diameter, a higher frequency may be selected.

2. Induction Heating Quenching Square Method and Inductor Selection

There are two kinds of induction hardening, square method: simultaneous quenching method and continuous quenching method.Mixer truck racewayAt the same time, during the operation of the heating and quenching method, the entire part of the workpiece to be quenched is put into the induction coil, and then heated once after rapid quenching and cooling; however, when the hardened area of the workpiece exceeds the maximum heating area allowed by the equipment When the area, the continuous heating and quenching method should be used, that is, the workpiece and the induction coil move relatively together to make the area to be hardened continuously pass through the induction coil. Therefore, according to the different methods of heating and quenching, there are synchronous heating inductors and continuous heating inductors.

The shape and size of the induction coil is typically designed according to the shape and size of the particular forging. Therefore, according to the heating form, the inductor can be divided into five categories: plane heating, cylindrical heating, inner hole surface heating, inner and outer surface heating and special surface heating inductor.

In the continuous heating and quenching process, the workpiece needs to be heated and cooled by spraying liquid, so the outlet end of the induction coil usually has a liquid spray hole.Mixer truck racewayAt the same time, when quenching, after the workpiece is heated to a predetermined temperature, most of it is quickly put into the quenching tank for cooling, so there is generally no spray hole on the induction coil.

Therefore, these factors must be fully considered when selecting the induction hardening square method and inductance, otherwise it will cause serious consequences. Mixer truck raceway. For example, when a workpiece needs to be heat treated with a continuous heating and self-spraying cooling inductor, if the heating inductor is misused at the same time, the power transmitted to the workpiece is not enough to heat the surface of the workpiece to the temperature specified by the process within the specified time, or because there is no spray hole on the induction coil, there is no method for quenching and cooling, or it cannot be used at all.

Selection of Cooling Medium for 3. Induction Heating Quenching

The cooling method of induction heating quenching mostly adopts the jet method, which requires that the quenching cooling medium does not burn and is not easy to block the nozzle hole.Mixer truck raceway. Medium carbon steel workpieces of simple shape are usually cooled by water spray. Low alloy steel parts and carbon steel parts with complex shapes should be sprayed with organic aqueous solutions, such as polyvinyl alcohol or emulsion; alloy steel with complex shapes (especially when the content of alloying elements is high) can be cooled by immersion in oil or by oil injection quenching with fire prevention measures; for forgings with large cross section, short heating time or good hardenability, workpiece self-cooling or compressed air spray cooling can also be used.