Shrink Fit Steel Gear onto Shaft With High Frequency Induction Heating Units
Objective Heat the bore of a hardened spur steel gear to shrink fit onto aĀ gear motor shaft. This is part of a chair for the disabled.
Material Steel gear 2.5ā (63.5mm) OD, .75ā (19mm) ID x .625ā (16mm)Ā thick, temperature indicating paint
Temperature 400 ĀŗF (204 ĀŗC)
Frequency 300 kHz
Equipment ā¢ DW-UHF-3.2 kW induction heating system, equipped with aĀ remote workhead containing two 0.66 Ī¼F capacitors for aĀ total of 1.32 Ī¼F
ā¢ An induction heating coil designed and developedĀ specifically for this application.
Process A four turn helical internal coil is used to heat the gear bore.
The coil is inserted into the gear bore and power is applied forĀ 90 seconds to reach the required 400 ĀŗF (204 ĀŗC) and expand
the gear bore. The gear is then placed on the shaft andĀ allowed to cool, creating the shrink fit between the gear and
the shaft.
Results/Benefits Induction heating provides:
ā¢ No pre-heat cycle, heat is available on demand
ā¢ Energy efficient, heats only the part, not the atmosphereĀ around it
ā¢ Controlled, even distribution of heating
ā¢ Faster production times
