November 2022 Volume 4

EQUIPMENT & TECHNOLOGY

1. Several induction equipment manufacturers require an input isolation transformer. This device can result in a 3 to 5 % reduction in energy efficiency of the system. On our systems we have eliminated the need for this device. 2. I recently read about a supplier who claims a 98% efficiency of their power supply, this is only possible when the unit is running at a very lower power level. In the typical higher normal power output of the power supply, you can expect the power supply to be 95% to 96% efficient. 3. The majority of induction forging lines have the induction coil and capacitors closely coupled with the induction coil positioned directly over the capacitor and inverter section of the system. This results in a substantial savings in energy eliminating approximately 5%of the overall losses as compared to older style systems

4. At AjaxTOCCOwe often vary the frequency and output power across the line in our PowerZone Induction Forge Heaters. We can control both the power level and frequency for each of the coils on the line. This feature allows us to better match for efficiency to the diameter of the load and the coils position in the line as the billet becomes non-magnetic as it reaches curie, thus saving additional, energy dollars. For customers who run a wide variety of rates, shapes, and diameters this results in substantial cost savings. For customers with more dedicated fixed sizes a simple single power supply and coil arrangement can suffice.

In the graph above we are showing the results of varying the power level across an induction systemwith three coils. You can see that most of the energy is induced into the billet within the first coil. This allows for the proper amount of time for this energy to soak into the core area of the billet which results in a properly heated billet. The set-up and operation of a system such as this is dependent upon advanced software which accurately calculates both the time and energy required to accomplish the proper heating of the billets so that the core and surface are within the desired differential. Relying solely on an optical pyrometer for control is never a clever idea because it is not possible for it to measure the core temperature of the load as it only views the surface. The software program accomplishes this task with great accuracy and the results easily loaded into the controls via an HMI interface. An optical pyrometer is then utilized at the end of the line to check the surface temperature at the discharge end of the machine.

FIA MAGAZINE | NOVEMBER 2022 23