Induction Hardening with IR Temperature Measurement
In many industries, the use of non-contact temperature measurement has become essential in monitoring and controlling production processes. In fact, high quality standards can only be guaranteed by precisely controlling temperature for even the smallest components.
During induction hardening and tempering, a particular spot of the workpiece (such as precision parts made of steel or cast steel) is heated up and subsequently quenched rapidly. For such contactless heating methods, usually only a special area on the surface of the workpiece is selectively heated.
This method of selectively heating and quenching a workpiece is critical in achieving the desired hardness of the material. If the temperature is too low, it will lead to insufficient surface hardness. However, if the temperature is too high, it may damage the workpiece so that it becomes unusable. By adjusting the induction coil, pieces in various shapes can be correctly heated up for the hardening process.
For efficient process monitoring and control through temperature measurement, LumaSense Technologies offers a wide range of infrared pyrometers. They are suitable for different industrial applications and can be configured for accurate measurements, even in the harshest working environments. The portfolio includes a wide range of instruments from standard-pyrometers and two-color pyrometers to composite solutions, which consist of pyrometers with integrated thermal imaging functionality.
Solutions:
The IMPAC Series 320 pyrometers are compact-sized and economically priced pyrometers for a variety of industrial applications. This series covers a wide temperature range from 75 °C to 1800 °C.
The Series 12 pyrometers with robust industry design enclosures and fiber optics are designed for emissivity independent temperature measurements in the harshest environments. These pyrometers measure from 300 °C. The fiber optical head can be used without additional cooling in ambient temperatures up to 250 °C. (IMPAC ISR 12-LO and IGAR 12-LO).
For measurement tasks with high reproducibility (as required in hardening processes), LumaSense offers IMPAC Series 6 Advanced pyrometers, which are available in different wavelength ranges and cover temperatures from 50 °C to 3000 °C. For this series a ratio pyrometer version (ISR 6 Advanced) is also available, covering a wide range of metal applications.
In order to detect and monitor the temperature distribution on the workpiece, a special hybrid-pyrometer with thermal imaging functionality has been developed by LumaSense. This new solution, IMPAC ISR 6 TI-Advanced, combines accurate two-color pyrometer measurement with thermal imaging display capability. This allows a specific indication of the temperature distribution of a dedicated region on the object’s surface.
The new ROI functionality contained in the supplied InfraWin software enables the definition and evaluation of specific “regions of interest”. When combined with an optional I / O module, it is possible for example to trigger external (switching-) contacts based on the temperature data of one or more ROI’s.
Conclusion:
The use of pyrometers for controlling induction processes provides significant advantages for the user:
- quick and easy process optimization
- maintaining exact quality-standards
- creation of robust, repeatable processes for monitoring of production
- enabling gapless process documentation for proofing process-safety