HIMMERWERK SINUS High Frequency Induction Heating Selection

Frequency selection and heating depth

The penetration depth (skin depth) of induction heating is inversely proportional to the square root of frequency: the higher the frequency, the shallower the heating layer; The lower the frequency, the deeper the penetration. The SINUS series covers a wide frequency range of 50kHz to 2000kHz, which can meet different process requirements.

3.1 Frequency and Typical Applications

Frequency Range Penetration Depth (Steel, 800 ℃) Typical Applications

50-200 kHz 1.5-3.0 mm through heat forging, large diameter bar heating, pipe annealing

200-500 kHz 0.7-1.5 mm gear quenching, shaft hardening, brazing

500-1000 kHz 0.3-0.7 mm small parts quenching, fine brazing, wire heating

1000-2000 kHz 0.15-0.3 mm micro parts surface hardening, film heating, sealing

3.2 Selection Guide

Select the scenario of SINUS 62/122 (50-200 kHz):

If the diameter of the workpiece is greater than 30mm, it needs to be heated through heat transfer

Preheating of forging blanks requires a small temperature difference between the core and surface

Annealing and normalizing of thick walled pipes or bars

Select the scenario of SINUS 55/105 (200-500 kHz):

Tooth surface quenching of medium modulus gears (modulus 2-6)

Surface hardening of shaft components, with a hardening layer depth of 0.8-1.5mm

Copper aluminum brazing requires controllable heating area

Select scenarios for SINUS 51/101/251 (500-1000 kHz):

Tooth surface quenching of small modulus gears (modulus<2)

Local hardening of precision parts with small heat affected zone

Hard alloy tool brazing

Select the scenario of SINUS 52/102/252 (1000-2000 kHz):

Surface hardening of small components such as screws and pins

Heating of thin sheet materials (thickness<0.5mm)

High frequency sealing and sealing

Key points of engineering installation and commissioning

4.1 Electrical Installation

Main power supply wiring:

Use 4-core cables (L1, L2, L3, PE), some models require neutral wire N (3 × 400V/N/PE).

Cable cross-sectional area: 5-12kW, recommended to be ≥ 4mm ²; 25kW is recommended to be ≥ 10mm ².

Install easy to operate isolation switches or circuit breakers near the generator.

Grounding:

It must be reliably grounded with a grounding resistance of less than 4 Ω.

Avoid sharing grounding electrodes with high-power equipment such as welding machines and frequency converters.

Electromagnetic compatibility (EMC):

Induction heating generator is a strong electromagnetic interference source, and the power cord should use shielded cables or pass through metal tubes.

The control signal lines (such as Profibus, Profinet, temperature feedback) should be wired separately from the power lines, with a spacing of ≥ 300mm.

Install an EMC filter (optional) at the power input end.

4.2 Cooling System Installation

Use hoses to connect the inlet and outlet of cooling water, with a recommended diameter of ≥ 12mm (inner diameter).

Install manual ball valves and pressure gauges in waterways to facilitate flow regulation.

When the water is first supplied, the air in the pipeline should be drained to prevent local overheating caused by air blockage.

It is recommended to install a conductivity meter in the water tank and regularly monitor the water quality.

4.3 Connection between heating head and coil

Connect the power cabinet and external heating head using the flexible coaxial cable provided with the device.

The coil (inductor) is customized according to the shape of the workpiece, usually wound with rectangular copper tube and cooled by water inside.

Gap between coil and workpiece: generally 2-5mm, the smaller the gap, the higher the efficiency, but it is necessary to prevent short circuits.

Before the first heating, the resonant frequency should be monitored using an oscilloscope or power meter to ensure that the generator is operating within the set frequency range.

4.4 Debugging steps

No load test: Without connecting the coil, check if the generator reports an error (usually no no-load operation is allowed, false load is required).

Water cooling system test: Check for leaks and confirm that the flow switch is functioning properly.

Low power trial heating: Set 10-20% power, observe the heating condition of the workpiece, and adjust the coil matching.

Parameter programming: Set parameters such as power, time, frequency (if adjustable) according to process requirements.

Repeatability verification: Heat multiple workpieces continuously and check temperature consistency.

Typical Application Explanation

5.1 Brazing and Welding

Induction brazing is one of the most common applications of the SINUS series, suitable for copper pipes, stainless steel pipes, hard alloy cutting tools, etc. Advantage:

Localized heating, without deformation of the base material

Controllable flow of solder and beautiful weld seam

Integrated automated production line, fast pace

Parameter example (copper brass joint, diameter 10mm):

Frequency: 300-500 kHz (SINUS 55 or 105)

Power: 5-8 kW

Heating time: 3-5 seconds

Coil: 2-3 turns, with an inner diameter slightly larger than the workpiece

5.2 Surface Quenching

Surface hardening of mechanical parts such as gears, shafts, and guide rails to improve wear resistance. Induction hardening can achieve extremely fast heating rates (tens to hundreds of degrees Celsius per second), followed by water spraying or immersion cooling.