ISO 10300-2-2023 PDF

Full title and description

ISO 10300-2:2023 — Calculation of load capacity of bevel gears — Part 2: Calculation of surface durability (macropitting). This is the third edition of Part 2 and provides the rating formulae, symbols and calculation methods used to assess surface durability (macropitting) of straight, helical (skew), spiral, Zerol and hypoid bevel gears.

Abstract

This document specifies methods of calculation for the load-carrying capacity of bevel gears with emphasis on surface durability (macropitting). It gives the formulae and symbols used for calculation, identifies the main influencing factors and states the intended application limits (types of bevel gears, tooth depth forms and restrictions such as virtual cylindrical gear assumptions and transverse contact ratio limits).

General information

• Status: Published.
• Publication date: 24 August 2023 (Edition 3, published 2023-08-24).
• Publisher: International Organization for Standardization (ISO).
• ICS / categories: 21.200 (Gears, gearings and transmission components).
• Edition / version: Edition 3 (2023).
• Number of pages: 35 pages.

Key bibliographic and lifecycle details (status, edition, page count and corrected-version note) are documented on the ISO catalogue entry for ISO 10300-2:2023.

Scope

ISO 10300-2:2023 provides calculation methods for assessing surface durability (macropitting) of bevel gears. The standard is intended for straight, helical (skew), spiral, Zerol and hypoid gears and applies to both tapered depth and uniform depth teeth. The rating formulae are based on the virtual cylindrical-gear approach and are restricted to bevel gears whose virtual cylindrical gears have transverse contact ratios ε_vα < 2; for bevel gears the sum of the profile shift coefficients of pinion and wheel is assumed to be zero. The standard warns that results may need confirmation by experience for extreme spiral angles, high effective pressure angles or unusually large face widths.

Key topics and requirements

• Definition of formulae and symbols for macropitting (surface durability) rating of bevel gears.
• Applicability to straight, helical (skew), spiral, Zerol and hypoid bevel gears and to tapered and uniform depth teeth.
• Assumptions and limits: virtual cylindrical gear model, transverse contact ratio ε_vα < 2, and zero sum of profile shift coefficients (reference to ISO 23509).
• Factors influencing load conditions (geometry, contact conditions, material and lubrication) and notes on when computed results should be validated by experience.
• Guidance on selecting rating factors for particular gear types and on establishing rating systems consistent with other parts of the ISO 10300 series.

Typical use and users

Primary users are gear designers and mechanical engineers working on bevel and hypoid gearboxes, OEM drivetrain teams, bearing and transmission component manufacturers, test laboratories, and software/tool vendors that implement ISO-based gear-rating calculations. The standard is used to produce consistent, engineering-based assessments of surface durability (macropitting) during design, verification and product development.

Related standards

ISO 10300-2:2023 is part of the ISO 10300 series on calculation of load capacity of bevel gears; closely related documents include ISO 10300-1:2023 (Introduction and general influence factors) and the geometry standard ISO 23509 (bevel and hypoid gear geometry) which provides geometric definitions and profile-shift conventions used by ISO 10300 rating methods. For cylindrical-gear rating methodology and background comparison, ISO 6336 (calculation of load capacity of spur and helical gears) is also commonly referenced by practitioners.

Keywords

bevel gears, macropitting, surface durability, load capacity, gear rating, hypoid, Zerol, spiral bevel, profile shift, contact ratio, ISO 10300

FAQ

Q: What is this standard?

A: ISO 10300-2:2023 is the third-edition international standard that specifies calculation methods and formulae for assessing the surface durability (macropitting) of bevel gears.

Q: What does it cover?

A: It covers the mathematical rating methods, symbols and influencing factors for macropitting resistance of straight, helical (skew), spiral, Zerol and hypoid bevel gears, including applicability limits and cautions for extreme geometries.

Q: Who typically uses it?

A: Gear designers, drivetrain/OEM engineers, gearbox manufacturers, testing laboratories and software/tool vendors implementing gear-capacity calculations commonly use this standard during design and verification.

Q: Is it current or superseded?

A: It is current: ISO 10300-2:2023 (Edition 3) was published on 24 August 2023 and replaces earlier editions (2014 and 2001). A corrected English version is noted on the ISO entry (corrected version: April 2025).

Q: Is it part of a series?

A: Yes — ISO 10300 is a multi-part series on calculation of load capacity of bevel gears; Part 1 gives general influence factors and introduction, and Part 2 addresses surface durability (macropitting). The series references geometry standards such as ISO 23509 for bevel/hypoid geometry.

Q: What are the key keywords?

A: Bevel gears, macropitting, surface durability, load capacity, gear rating, hypoid, profile shift, contact ratio, ISO 10300.