ISO/TR 10300-30:2024

Calculation of load capacity of bevel gears — Part 30: ISO rating system for bevel and hypoid gears — Sample calculations

This document provides sample calculations for the load capacity of different bevel gear designs, determined according to the methods and formulae of the ISO 10300 series. The initial geometric gear data necessary for these calculations are according to ISO 23509.

The term “bevel gear” is used to mean straight, helical (skew), spiral bevel, zerol and hypoid gear designs. Where this document pertains to one or more, but not all, the specific forms are identified.

The manufacturing process of forming the desired tooth form is not intended to imply any specific process, but rather to be general in nature and applicable to all calculation methods of the ISO 10300 series. The fact that there are bevel gear designs with tapered teeth and others where the tooth depth remains constant along the facewidth (uniform depth) does not require to apply Method B2 for the first and Method B1 for the second tooth configuration.

The rating system of the ISO 10300 series is based on virtual cylindrical gears and restricted to bevel gears whose virtual cylindrical gears have transverse contact ratios of ε_vα < 2. Additionally, the given relations are valid for bevel gears of which the sum of profile shift coefficients of pinion and wheel is zero (see ISO 23509).

WARNING          The user is cautioned that when the formulae are used for large average mean spiral angles, (β_m1 + β_m2)/2 > 45°, for effective pressure angles, α_e > 30° and/or for large facewidths, b > 13 m_mn