TURN KEY NON-CONTACT TEMPERATURE CONTROL AND MONITORING OPTIONS FOR ULTRAFLEX SYSTEMS
Achieving and maintaining the desired temperature of the heated part is a critical aspect of most induction heating processes. The Ultraflex systems can be controlled in several ways to ensure accurate temperature control and monitoring:
TEMPERATURE CONTROL METHODS
- Pre-programmed steps – All Ultraflex products feature multiple programs that can be entered and used for ensuring good temperature control. Each program has multiple steps where time, power level or ramp rate can be entered to achieve accurate temperature profile. Though this method has no indication or measurement or the actual temperature, it is acceptable for a lot of applications where good position control and repeatability can be ensured.
- Temperature Controllers – When the process requires accurate monitoring and control of the temperature, a Temperature controller unit must be used. Ultraflex offers the following options:
- Integrated Temperature control module – Selected Ultraflex products come with built-in temperature control module which can be used for accurate temperature control. The module can be accessed, and control parameters set through the User interface of these products.
- Temperature Controller unit (TC-01) – Ultraflex offers a turn-key external Temperature controller unit. This unit is designed to easily integrate with all Ultraflex induction systems and IR pyrometers. It is suitable for rapid temperature changes or when more complex thermal profiles must be achieved. They can operate with all standard IR sensors and thermocouples. They also come with USB port for easy setup or download to a PC.
- Advanced Temperature Control – Ultraflex offers custom engineered solutions for demanding temperature control processes or multi-point temperature control, monitoring and recording is required. Optional software packages for data logging and acquisitions are also available.
THEMPERATURE MEASUREMENT METHODS
- Thermocouples – Depending on the application, thermocouples can be a viable option for induction heating. When contact method of measurement is possible and the temperatures are usually below 1000C, the thermocouples can be a reliable and inexpensive choice. It must be noted that the thermocouples are metallic and could be affected by the electromagnetic field. For this reason, the placement of the thermocouples must be carefully selected, preferably outside of the induction filed.
- Non-contact Infrared Temperature Pyrometers – IR pyrometers can rapidly and accurately measure temperature of an object without being in contact with it. They offer several advantages:
- Can measure much higher temperatures (3000C+)
- Fast response time
- Fast and accurate temperature reading
- Can be located outside of the RF field
- Reading is not affected by the RF field
Use of Temperature Control in Induction Heating
Demonstrate temperature control utilizing an optical pyrometer/controller to heat the top knurled section of a magnetic steel surgical instrument tube to 93°C (200°F) and maintain temperature.
Magnetic stainless steel tube.
Temperature: 93°C (200°F)
Power: 1.5 kW
Time: 2 seconds
- The dual temperature pyrometer was sighted on the stainless steel tube to permit the sight lights to focus on the top section of the tube.
- The emmisivitiy was set on the controller at 0.6 for bright stainless steel.
- Power was limited to 10 kW to avoid over-shooting the temperature.
Results and Conclusions:
- Using a temperature controller sighted on the heated end of the stainless steel tube will control the temperature as required.