Induction heating equipment, according to its output frequency, can be roughly divided into: ultrasonic induction heating equipment, high frequency induction heating equipment, medium frequency induction heating equipment, etc. Different heating processes require different frequencies. If the frequency is selected incorrectly, then Can not meet the heating requirements, and it is easy to cause damage to the workpiece. To correctly select the frequency, we need to understand the heating process requirements of the product. Generally speaking, there are several situations:
1. Heat penetration of the workpiece, such as: fasteners, standard rooms, auto parts, hardware tools, hot upsetting and hot rolling of twist drills, etc. The larger the diameter of the workpiece, the lower the frequency should be, such as:
Suitable for high frequency (100-500KHz) below Φ4mm
Φ4-16mm for high frequency (50-100KHz)
Φ16-40mm for super audio (10-50KHz)
Medium frequency (0.5-10KHz) for Φ40mm and above
2. Heat treatment, shafts, gears, quenching and annealing of stainless steel products, etc. Take quenching as an example, the shallower the quenching layer of the workpiece, the higher the frequency, the deeper the quenching layer, the lower the frequency, such as:
The quenching layer is 0.2-0.8mm for 100-250KHz high frequency
1.0-1.5mm for 40-50KHz high frequency, super audio
1.5-2mm for 20-25KHz super audio
2.0-3.0mm for 8-20KHz super audio, intermediate frequency
3.0-5.0mm for 4-8KHz IF
5.0-8.0mm for 2.5-4KHz IF
3. Brazing, drill bits, turning tools, reamers, milling cutters, drill bits, etc. and composite welding of different materials at the bottom of the stainless steel pot, the larger the welding volume, the lower the frequency. Take turning tool welding as an example, such as:
Tools below 20mm are suitable for 50-100KHz high frequency
Tools above 20-30mmmm are suitable for 10-50KHz high frequency, super audio
Tools above 30mm are suitable for 1-8KHz intermediate frequency
4. Smelting gold, silver, copper, lead and other precious metals
According to the efficiency of the furnace and production, high frequency can be selected for small capacity, and super audio frequency and medium frequency are mostly selected. Super audio frequency can meet the general application of die casting industry, and can melt 200KG aluminum ingots per hour.