preheat Welding - ultraflex Induction preheat postheat applications

Heat a Magnetic Steel part above 350°F (176.7°C) in thirty minutes. Allow heat to “soak” and part temperature to equalize, such that temperature across entire part reaches 350°F (176.7°C).

Recommended Equipment
The recommended equipment for this application is the UPT M25/25-AC

Outside cylinder (22” tall, 30”OD, 27”ID)
Inner ring (0.9” thick, 27”OD, 16”ID)
Temperature Indicating Paint
High temperature insulating fiber

Key Parameters
Power: Up to 25 kW
Temperature: 176.7°C (350°F)
Time: 40 minutes

Process Steps

  1. Entire part was enclosed by high temperature insulating fiber to minimize heat dissipation during equalization.
  2. Coil centered over insulation with 1.5” between turns.
  3. Heat entire part for 23 minutes to 37°C (100°F) above desired temperature.
  4. Allow heat to even out between parts until equal temperature is reached across the parts.

Results and Conclusions
The target temperatures were reached in the material after 23 minutes of heating and 20 minutes of “soak” time with the air-cooled unit. More optimal results could be found in fixturing the coil to reduce variation in the coil spacing. Optimal coil spacing was found to be 1.5” for a five turn coil.


Request information or contact us about this application. Reference info: Application Note 3463-5099