Hot-rolled bars are quenched and tempered with medium frequency induction heating equipment

At present, the quenching and tempering treatment of hot-rolled bars adopts through-type heat treatment using oil, natural gas or electric energy for heating. After quenching, it is immersed and cooled in a quenching water tank, and finally heated and tempered in a tempering furnace. The properties of the steel obtained by this quenching and tempering treatment method are extremely unstable, seriously reducing the processing performance of the steel and the usability of parts. Using medium-frequency induction heating equipment to quench and temper hot-rolled bars can completely avoid the shortcomings of traditional quenching and tempering, and obtain steel with stable mechanical properties.

The method of medium frequency induction heating is used to quench and temper hot-rolled bars of carbon structural steel and low alloy structural steel. In the 1971s, it has been applied in metallurgical plants in the United States, France, Russia and other countries, and many medium frequency lines have been built. Induction heating quenching and tempering production line, these steel grades are mostly used to manufacture parts for automobiles, tractors, and machine tools. In induction heating quenching and tempering treatment of rods, due to limitations of cooling conditions, the diameter of the rods for modulation treatment is limited to 60m. After the quenching and tempering treatment of rods with a diameter larger than 60mm, it is found that there is insufficient hardness in the core. Medium frequency induction heating can not only temper round rods, but also square and polygonal strips.

The performance characteristics of hot-rolled bars treated with medium frequency induction heating and quenching and tempering are as follows:

The hot-rolled bar that has been quenched and tempered by medium-frequency induction heating is rapidly heated to austenite and quenched to obtain a finer martensite structure, and then tempered at high temperature to obtain fine tempered sorbite. This tempered sorbite has high tensile strength and yield strength, as well as good plasticity and toughness.

Features of medium frequency induction heating equipment for hot rolled bar quenching and tempering treatment:

1. Fast heating speed: Generally, it only takes a few seconds to more than ten seconds to heat the workpiece to the required quenching temperature.

2. The production efficiency is high, the quenching depth is easy to control, mechanization and automation are easy to implement, and it is suitable for mass production.

3. Highly efficient and energy-saving, it can save more than 60% of electricity than electronic tube equipment.

4. Easy to install, just connect the power supply and water pipe, and it can be completed in 10 minutes.

5. The equipment has constant current and constant power control functions, which greatly optimizes the heating process of metal, achieves efficient and rapid heating, and gives full play to the superior performance of the product.

6. It is light in weight, small in size and easy to install. Just connect it to the 380V three-phase power supply, water in and out, and it can be completed in a few minutes. It occupies a small area, is simple to operate and can be learned in a few minutes.

7. The self-controlled type can adjust the heating time, heating power, holding time, holding power and cooling time; it greatly improves the quality of heating products and the repeatability of heating, and simplifies workers' operating techniques.

8. Especially safe, the output voltage is lower than 36V, eliminating the risk of high-voltage electric shock.

9. The equipment has complete automatic protection functions such as overcurrent, overvoltage, overtemperature, water shortage, and lack of phase, and is equipped with a fault self-diagnosis and alarm system.

10. The heating efficiency is as high as over 90%, and the energy consumption is only 20%-30% of the high frequency of old-fashioned electronic tubes. It uses almost no electricity in standby mode, and can work continuously for 24 hours.

11. The sensor can be freely and quickly disassembled and replaced, and the faster heating greatly reduces the oxidation deformation of the workpiece.