High Speed Heating by Induction Heating System

One of the recent outstanding developments in the heat treating field has been the application of induction heating to localized surface hardening. The advances made contingent with the applica­tion of high frequency current have been nothing short of phenomenal. Starting a comparatively short time ago as a long-sought-after method of hardening bearing surfaces on crankshafts … Read more

Induction Preheating Hot Heading

Induction Preheating Hot Heading For Single Rod With IGBT Induction Heater

Objective Heat a waspaloy rod to 1500ºF (815.5ºC) for hot heading application
Material Waspaloy rod 0.5” (12.7mm)OD, 1.5” (38.1mm) length, ceramic liner
Temperature 1500 ºF (815.5ºC)
Frequency 75 kHz
Equipment • DW-HF-45KW induction heating system, equipped with a remote workhead containing two 1.32μF capacitors for a total of .66μF
• An induction heating coil designed and developed specifically for this application.
Process A seven turn helical coil is used to heat the rod. The rod is placed inside the coil and power is applied for two seconds providing enough heat to penetrate the inner core. An optical pyrometer is used for close loop temperature control and a ceramic liner is used so the rod does not touch the coil.
Results/Benefits Induction heating provides:
• Low pressure and minimal residual stress
• Better grain flow and microstructure
• Even distribution of heating
• Improved production rates with minimal defects

induction preheating hot heading

High Frequency Induction Brazing Diamond Inserts

High Frequency Induction Brazing Diamond Inserts

Objective: Induction Brazing diamond inserts to a steel drilling ring

Material : • steel ring and diamond inserts • Braze shim preform • Flux

Temperature :1300 – 1350 (700 – 730) °F (°C)

Frequency :78 kHz

Equipment: DW-HF-15kW, induction heating system, equipped with a remote heat station containing two 0.5 μF capacitors (total 0.25 μF) An induction heating coil designed and developed specifically for this application.

Process: A multi-turn, internal-external helical coil (A) is used to generate the required heating pattern. Initial tests on the ring alone determine system tuning. Flux is applied to the part and the braze shims are inserted into the counter-bored holes (B). This is followed by the synthetic diamonds. The part is loaded into the coil and weight is placed onto the diamonds (C). RF Induction Heating power is applied until the braze flows. The power is turned off and the part air cools to room temperature.

Results/Benefits • reduced ring warping compared to furnace induction heating • decreased cycle time due to reduced ramp-up and cooldown times