The furnace temperature uniformity of controlled atmosphere carburizing equipment is controlled at + 5C and carbon potential accuracy is controlled at + 0.02%; the furnace temperature uniformity of controllable atmosphere nitriding equipment is controlled at + 3C and nitrogen potential stability is controlled at kn + 0.02; the surface hardness, hardened layer depth, metallographic structure and other thermal treatment indexes of the wind turbine gear treated shall fully meet the product technical requirements.