Three stages of round steel quenching and tempering production line equipment.

1. Quenching stage of induction heating furnace

The quenching stage of the induction heating furnace is arranged at the back of the induction heating furnace frame and consists of a circulating water cooling system. When the bar material is heated to the quenching temperature, it comes out of the induction heating furnace, and the reasonable and effective use of circulating water cooling equipment can make the bar material to be violently cooled here. On the surface of the bar, the cooling value exceeds the critical value of martensite, so a martensite structure can be formed on the surface to achieve the purpose of quenching.

2. The tempering stage of induction heating furnace

The quenched bar stock is transported by the conveying system into the induction heating furnace for tempering. After reaching the tempering temperature, the bar is transported out of the induction heating furnace by the rolling table. The bar is exposed to the air, and the heat in the core will be affected. Transfer to the surface layer and temper the surface to achieve the purpose of tempering.

3. The cooling stage of induction heating furnace

This stage occurs later, mainly the austenite in the core undergoes isothermal transformation to obtain the final state of the metallographic structure.

Round steel quenching and tempering is an effective method to improve the quality, which can improve the internal structure of the rolled piece, so as to obtain better mechanical strength. The on-line heat treatment of the rolled product can form the martensite structure of the surface layer by quenching, and through the core heat transfer, the surface layer martensite is self-tempered, so that the surface layer can obtain the tempered martensite structure. The core has a large temperature drop due to the cooling of the surface layer, which refines the pearlite structure generated, which not only increases the hardness of the surface layer, but also improves the core structure. In addition, online round steel quenching and tempering can enhance the mechanical properties of the steel plate and reduce the content of carbon and alloying elements. Online heat treatment combines controlled heating, controlled rolling and controlled cooling into a complete energy-saving production process, so it can save a lot of energy and reduce costs.