GB/T 2363-2025 Active

This document specifies the grading method and tolerance values for the accuracy of the tooth surfaces of single small-module involute cylindrical gears within the following parameter ranges:
—— 0.1mm ≤ m. < 0.5mm;
—— 5 ≤ z ≤ 200;
—— 0.5mm ≤ d ≤ 100mm;
—— 0.2mm ≤ b ≤ 10mm;
—— ≤ 45°.
Where:
m —— normal module;
z —— number of teeth;
d —— pitch circle diameter;
b —— tooth width (axial);
β —— helix angle.
Note 1: The tolerance values for accuracy are also known as the allowable values for deviations.
Note 2: The accuracy grade of a gear obtained according to this document is not directly related to its actual performance in use.
This document is applicable to the evaluation of the manufacturing level of small-module gears made from metal and powder metallurgy materials.