Square steel billet induction heating furnace

Square billet induction heating equipment is a core device used to quickly and accurately heat square section steel billets (square billets) to the target temperature before rolling, forging, or heat treatment. It is gradually replacing traditional gas stoves and oil stoves with its high efficiency, cleanliness, and controllability.

Core working principle

Based on electromagnetic induction and skin effect.

Induction coil: When an alternating current passes through an induction coil made of copper tube, an alternating magnetic field of the same frequency is generated around it.

Eddy current generation: When a metal billet passes through or is placed in this magnetic field, strong eddy currents are induced inside it.

Self heating: Due to the resistance characteristics of metals, these eddy currents generate Joule heating when flowing inside the billet, causing the billet to start heating from the inside.

Temperature equilibrium: Heat is transferred from the surface to the interior through thermal conduction. For large section billets, it is usually necessary to equip them with insulation and heat equalization sections, which utilize the internal heat conduction of the billet to make the core surface temperature uniform.

A complete square steel billet induction heating furnace usually includes:

Feeding and conveying system: automatic feeding machine, roller conveyor or walking beam, used to continuously and smoothly feed cold or warm billets into the heating line.

Induction heating power supply: The core power source is usually an intermediate frequency (MF, 100Hz-10kHz) or ultrasonic frequency power supply. For large-sized billets, power frequency (50/60Hz) can also be used. The modern mainstream adopts IGBT transistor variable frequency power supply, which has high efficiency and precise control.

Induction heating furnace body:

Sensor (coil): made of rectangular copper tube wound with advanced refractory material lining (such as knotting material or insulation sleeve). According to the heating process, it can be divided into two methods: longitudinal heating (the long axis direction of the billet passes through the coil) and transverse heating (the billet passes horizontally). For square billets, longitudinal heating is more common and efficient.

Furnace structure: including coil bracket, water cooling system, magnetic conductor (used to improve efficiency), insulation layer, etc.

Temperature measurement and control system:

Infrared thermometer: Non contact real-time monitoring of the surface temperature of the billet, which is a key sensor for closed-loop control.

PLC control system: Based on the set heating curve and temperature feedback, it automatically adjusts the power supply, frequency, and conveying speed to achieve precise temperature control.

Discharge and unloading system: Send the heated billet to the rolling mill or the next process.

Water cooling system: provides circulating cooling for key components such as induction coils, power supplies, capacitors, etc., ensuring stable operation of the equipment.

If you are also interested in this machine,please don’t hesitate to contact us:

Overseas manager: Tom Wang

Email:tom@foreverfurnace.com

Phone/Wechat/Whatsapp:+86 13303078975