Analyze the advantages and limitations of using medium frequency induction heating machines for induction heat treatment of parts

First, let's take a look at the advantages of using medium frequency induction heating machines to perform induction heat treatment on parts, as follows:

(1) Surface quenching. Surface quenching gives the workpiece a hard shell and a tough core. Therefore, it can replace part of the carburizing, tempering and nitriding processes and save the alloy elements of the material. Due to the short heating time, there is very little oxide scale and small deformation.

(2) Partial quenching of the workpiece can be performed. It can accurately heat the parts of the workpiece that need to be quenched, especially when using magnetic conductors and using high power densities.

(3) Energy-saving heat treatment. Using a medium frequency induction heating machine to perform induction heat treatment on parts has greater energy consumption than carburizing, nitriding, and quenching and tempering. When the difference between the quality of the quenched part of the workpiece and the overall quality is greater, its advantages are also greater. Significantly.

(4) Rapid heat treatment. The heating time of induction quenching is calculated in seconds, generally 2~10s, and the production cycle is also short, especially when self-tempering or random induction tempering is used. This process is similar to the machining process. Therefore, the application of modern medium-frequency induction heating machines in parts heat treatment has been realized in production lines or automatic lines.

(5) Clean heat treatment. The quenching cooling medium used in induction quenching is generally water or an aqueous solution with additives. During quenching, there is almost no oil smoke and the working environment is good.

(6) Facilitate mechanization and automation. Mass-produced induction hardened parts are generally equipped with devices such as automatic feeders, robots to pick up workpieces, and robots to operate sensors to reduce physical labor.

Although at present, the use of medium frequency induction heating machines has been very common in the induction heat treatment of parts and has many advantages, it is undeniable that there are still some limitations, as follows:

(1) Induction heat treatment is not suitable for complex workpieces. For example, some transmission gears require high wear resistance and good toughness at the core, and currently still use nitriding process.

(2) Special tooling, namely a sensor, is required. A heat treatment furnace can hold a variety of workpieces for heating, carburizing, and nitriding, while induction hardening requires one type of sensor for each part, and even a special positioning fixture, etc., so the tool cost is high. It is only suitable for mass production of one or one race of workpieces.

(3) The investment cost of supporting equipment is high. Compared with general heat treatment equipment, the use of medium frequency induction heating machines to perform induction heat treatment on parts requires the corresponding variable frequency power supply, quenching machine tools, sensors, and accessory cooling water, quenching cooling medium circulation devices, etc., and its investment costs are relatively high. , the maintenance technology and cost are also higher than those of general heat treatment equipment.