English
Induction annealing is a heat treatment process that uses electromagnetic induction heating to reduce the hardness of metals and improve their plasticity and toughness.
Electromagnetic Induction: Induction annealing uses high-frequency alternating current to generate a magnetic field in an induction coil, which in turn induces eddy currents in the metal workpiece. These eddy currents generate heat due to the resistance of the metal, thereby heating the workpiece. This method can achieve rapid and uniform heating with high thermal efficiency.
Material Preparation: Place the metal workpieces to be annealed inside the induction coil.
Induction Heating: Generate a magnetic field in the induction coil through high-frequency current, inducing eddy currents to rapidly heat the workpiece to the annealing temperature.
Soaking: After reaching the annealing temperature, maintain it for a period to allow changes in the internal microstructure of the workpiece, reduce internal stress, and promote grain growth.
Cooling: After soaking, the workpiece undergoes controlled cooling, usually slow cooling, to maintain the annealing effect.
Post-treatment: Depending on the requirements, further machining or surface treatment may be performed.
Rapid Heating: Induction annealing can achieve rapid heating, significantly reducing heating time.
Energy Efficiency: Due to high thermal efficiency, induction annealing is more energy-efficient than traditional furnace annealing methods.
Uniform Heating: Induction heating ensures uniform temperature across all parts of the workpiece, avoiding inconsistent heating in traditional methods.
Flexibility: Suitable for various shapes and sizes of workpieces, including complex geometries.
Improved Safety: Only the workpiece itself is heated, reducing the risk of burns and fire hazards for on-site workers.
Metal Materials: Widely used in the annealing treatment of steel, aluminum, copper, and other metal materials.
Mechanical Parts: Used to improve the plasticity and toughness of mechanical parts and reduce processing stress.
Welded Structures: Used to eliminate residual stress after welding to prevent welding cracks.
It utilizes a series resonant circuit, which offers the benefits of a high power factor, minimal harmonic distortion, easy startup, and a low failure rate.
Equipped with Siemens (Infineon IGBT) as the inverter, digital phase synchronization technology is employed to ensure that the IGBT operates in a Zero Current Switching (ZCS) state, enhancing the service life and stability of the IGBT and reducing equipment loss.
The principle of electromagnetic induction is used, where alternating current generates eddy currents inside the material to be heated (i.e., the workpiece), and the workpiece is heated by the energy of these eddy currents. The induction coil does not come into direct contact with the heated workpiece. The coil transfers the electrical energy of the equipment to the workpiece through a magnetic field, transforming electrical energy into thermal energy within the workpiece.
The machine is designed as an automatic line with three workstations: a feeding station, a heating station, and an unloading station, specifically for bullet shell annealing.
The electrical system of the entire machine uses high-precision programming technology to achieve automatic control of the working program. It can store annealing process programs for a variety of workpieces.
The machine has the capability for both manual and automatic operation, suitable for both batch and single-part production, with quick and convenient debugging. It features an advanced and reliable structure, excellent performance, stable operation, and a long design life.
The machine consists of a bed, feeding part, discharging part, moving air claw mechanism, workpiece rotating lifting part, inductor dual position conversion and adjusting part, water spray, and water collection tank, among other stainless steel pipes, controls, and electrical appliances.
Unlike conventional mechanical or hydraulic transmission, this machine is primarily designed for bullet shell annealing. Due to its high positioning accuracy, the heating position of the workpiece can be set according to the different technological requirements of the workpiece during annealing by numerical control programming. Continuous automatic annealing of the workpiece can be accomplished by adjusting the heating speed or temperature, with the workpiece rotation speed regulated by frequency conversion.
Equipment Principle
Air-cooled part: The working fluid (soft water or other liquids) circulates in the coil of a closed cooling tower. The heat of the fluid is absorbed by the tube wall of the coil and discharged from the machine through the fan at the top.
Water-cooled part: When the fluid temperature is too high (exceeding the set temperature), the sprinkler system is automatically activated. The spray pump sprays water onto the wall of the hot and humid tube, forming a water film that absorbs a large amount of heat through evaporation (evaporation latent heat). Some of the sprayed water becomes steam, carried away by the airflow, while the unevaporated water droplets fall into the sink for the next cycle. The fluid in the coils circulates in a closed loop with no theoretical consumption. The consumption of spray water is only 0.1-0.2% of the unit flow rate.
Equipment Structure
Main engine: The main cooling tower consists of a shell, copper cooler, exhaust system, spray system, dehydrator, sink, etc.
Auxiliary machine: The auxiliary machine is mainly a cooling tower control system, composed of a water pump, stainless steel water tank, and temperature control system.
