Gears and gear pairs specify 12 accuracy levels, with the first level having the highest accuracy and the 12th level having the lowest accuracy. The accuracy grades of the two gears in the gear pair are generally the same, but they can also be different.
Gear tolerances and limit deviations are divided into three groups Gear tolerances and limit deviations are grouped
Gears and gear pairs specify 12 accuracy levels, with the first level having the highest accuracy and the 12th level having the lowest accuracy. The accuracy grades of the two gears in the gear pair are generally the same, but they can also be different. Gear tolerances and limit deviations are divided into three groups Gear tolerances and limit deviations are grouped
Tolerance group Tolerance and limit deviation items Error characteristics Main influence on transmission performance
Ⅰ Fi ′, FP, FPk Fi ″, Fr, Fw take the error of one revolution of the gear as the cycle accuracy of transmitting motion
Ⅱ fi ′, fi ″, ff ± fPt, ± fPb, ffβ Errors that occur repeatedly many times within a week of the gear transmission stability, noise, vibration
Ⅲ The uniformity of the error load distribution of Fβ, Fb, ± FPx tooth line according to different requirements, different tolerance levels are allowed for each tolerance group, but within the same tolerance group, the tolerances and limit deviations should be kept the same Accuracy level. Selection of gear transmission accuracy grade
Machine type and accuracy class
Measuring gear 3 ～ 5
General purpose reducer 6 ～ 8
Reducer for turbine 3 ～ 6
Truck 6 ～ 9
Metal cutting machine 3 ～ 8
Pinions of tractors and rolling mills 6 ～ 10
Aeroengine 4 ～ 7
Lifting machinery 7 ～ 10
Light car 5 ～ 8
Winch for mine 8 ～ 10
Diesel locomotive and electric locomotive 5 ～ 8
Agricultural machinery 8 ～ 11