**What is Induction Heating?**
Induction heating is a process that uses electromagnetic induction to heat conductive materials, primarily metals. It is widely used in metalworking for processes such as thermal treatment, welding, and melting. The basic idea behind induction heating is to generate an alternating magnetic field using an induction coil, which induces eddy currents within the material being heated. These currents produce heat through resistance, allowing for efficient and localized heating.
An induction heating system typically consists of three main components: an induction coil, an AC power source, and the workpiece. The coil can be designed in various shapes depending on the application. When an alternating current passes through the coil, it creates a magnetic field that penetrates the workpiece, inducing currents inside it. This method allows for rapid and precise heating without direct contact, making it ideal for industrial applications.
**Principle of Induction Heating**
The principle of induction heating is based on three fundamental concepts: electromagnetic induction, the skin effect, and heat conduction. In this process, the workpiece and the inductor act like a transformer. The primary coil (inductor) generates an alternating magnetic field, which induces a current in the secondary coil (workpiece). This induced current, known as eddy current, flows through the material and produces heat.
At higher frequencies, the skin effect becomes more pronounced, causing the current to concentrate near the surface of the workpiece. This means that most of the heating occurs at or just below the surface, which is particularly useful for surface hardening. The depth at which the current density drops to about one-third of its surface value is called the "skin depth." Approximately 86.5% of the heat is generated within this thin layer, making induction heating highly efficient for targeted heating.
**Key Effects in Induction Heating**
1. **Surface Effect**: When an alternating current flows through a conductor, the current density is not uniform across the cross-section. Higher frequency currents tend to flow near the surface due to the skin effect.
2. **Proximity Effect**: When two adjacent conductors carry high-frequency currents in opposite directions, the current tends to flow on the inner sides of the conductors. If the currents are in the same direction, the current moves to the outer sides.
3. **Circulation Effect**: In a ring-shaped conductor, high-frequency currents tend to concentrate inside the ring, creating a higher current density in that area.
4. **Sharp Angle Effect**: At sharp corners of the workpiece, the magnetic field lines tend to concentrate, leading to excessive current density and potential overburning.
5. **Magnetizer Driving Effect**: To control the current distribution, a magnet is sometimes placed near the inductor. This helps redirect the magnetic field and improve heating efficiency, especially when heating internal surfaces.
**Induction Heating Applications**
Induction heating is commonly used for surface hardening, where the surface of a metal part is rapidly heated and then cooled to increase its hardness. This method offers several advantages over traditional heating techniques. For example, it provides faster heating, finer microstructure, and reduced distortion. Additionally, it minimizes oxidation and decarburization, making it suitable for precision parts that require minimal post-processing.
The process involves placing the workpiece inside an inductor made of a hollow copper tube. When a high-frequency or medium-frequency AC current is applied, it induces a current on the surface of the workpiece, heating it quickly—often reaching temperatures between 800°C and 1000°C in seconds. After heating, the part is immediately quenched with water or oil, resulting in a hardened surface while the core remains cool.
**Advantages of Induction Heating Surface Quenching**
1. Fast heating speed, increasing the austenite transformation range and reducing transition time.
2. Produces fine martensite structure, resulting in higher hardness and improved fatigue strength.
3. Minimizes oxidation and decarburization, allowing for direct assembly after treatment.
4. Easy to control the depth of the hardened layer and integrate into automated systems.
**Top Induction Heating Equipment Manufacturers**
**1. Beijing Million Electronic Technology Center**
Located in the Haidian High-Tech Park in Beijing, Beijing Million Electronic Technology Center is a leading company specializing in instrumentation, gas detection, metal detection, environmental protection equipment, and more. With operations spanning 33 provinces and municipalities in China, the company has built a strong reputation for quality, reliability, and customer satisfaction. Its extensive product range covers multiple industries, from healthcare to agriculture and mechanical equipment.
The company’s large-scale inventory, advanced technology, and comprehensive after-sales service make it a trusted name in the industry. It has earned widespread recognition from both customers and professionals alike.
Radiators in this case are manufactured with Stainless steel (SS304, SS316 and SS316L).
These radiators are manufactured with both 1mm CRCA sheet and 1.2 mm CRCA sheet as required and centre distance varying from 600 mm to 4000 mm. Stainless steel radiators can be offered with and without paint.
Through the method, the stainless steel plate type radiator for the transformer is simple in structure, free of complex treatment process on the surface of the radiator, not prone to oxidizing and corroding, long in service life, and high in welding strength.
Stainless Steel Radiator,Stainless Steel Transformer Radiator,Stainless Steel Cooling Radiator,Stainless Steel Weather Proof Radiator
Shenyang Tiantong Electricity Co., Ltd. , https://www.ttradiator.com