Helical Bull Gear – TSH Process vs Conventional Induction Hardening

The conventional heat treat process for the large 13” helical gear is gas carburizing.  This part could also be induction contour hardening using conventional induction technology.

TSH Processed Contour Induction Hardening
Steel 60LH 1552/4150H
Hardening Cycle Time 3 minutes 2 seconds
Power Supply Low frequency Dual Frequency
Coil Power Requirement Low High
Harden Depth Control Steel Thermal Profile
Core Heat Treatment Yes No
Tempering Residual Heat Furnace Tempered
Residual Stress High Compressive High Compressive
Fatigue Life 1 1

Bull Gear