Introduction

The ISO 6336 series consists of International Standards, Technical Specifications (TS) and Technical Reports (TR) under the general title Calculation of load capacity of spur and helical gears (see Table 1).

— International Standards contain calculation methods that are based on widely accepted practices and have been validated.
— TS contain calculation methods that are still subject to further development.
— TR contain data that is informative, such as example calculations.

The procedures specified in ISO 6336‑1 to ISO 6336‑19 cover fatigue analyses for gear rating. The procedures described in ISO 6336‑20 to ISO 6336‑29 are predominantly related to the tribological behaviour of the lubricated flank surface contact. ISO 6336‑30 to ISO 6336‑39 include example calculations. The ISO 6336 series allows the addition of new parts under appropriate numbers to reflect knowledge gained in the future.

Requesting standardized calculations according to ISO 6336 without referring to specific parts requires the use of only those parts that are designated as International Standards (see Table 1 for listing). When requesting further calculations, the relevant part or parts of ISO 6336 need to be specified. Use of a Technical Specification as acceptance criteria for a specific design needs to be agreed in advance between manufacturer and purchaser.

Table 1 — Overview of ISO 6336

Calculation of load capacity of spur and helical gears	International Standard	Technical Specification	Technical Report
Part 1: Basic principles, introduction and general influence factors	X
Part 2: Calculation of surface durability (pitting)	X
Part 3: Calculation of tooth bending strength	X
Part 4: Calculation of tooth flank fracture load capacity		X
Part 5: Strength and quality of materials	X
Part 6: Calculation of service life under variable load	X
Part 20: Calculation of scuffing load capacity — Flash temperature method		X
Part 21: Calculation of scuffing load capacity — Integral temperature method		X
Part 22: Calculation of micropitting load capacity (replaces: ISO/TR 15144‑1)		X
Part 30: Calculation examples for the application of ISO 6336‑1, ISO 6336‑2, ISO 6336‑3 and, ISO 6336‑5			X
Part 31: Calculation examples of micropitting load capacity (replaces: ISO/TR 15144‑2)			X

NOTE At the time of publication of this document, some of the parts listed here were under development. Consult the ISO website.

This document provides worked examples for the application of the calculation procedures defined in ISO 6336‑1, ISO 6336‑2, ISO 6336‑3 and ISO 6336‑5. The example calculations cover the application to spur, helical and double helical, external and internal cylindrical involute gears for both high speed and low speed operating conditions, determining the ISO safety factors against tooth flank pitting and tooth root bending strength for each gear set. The calculation procedures used are consistent with those presented in ISO 6336‑1, ISO 6336‑2, ISO 6336‑3 and ISO 6336‑5, unless qualifying comments are provided. Where qualifying comments have been included in this document, they reflect areas of the calculation procedures presented in the current standards where points of clarification are required or editorial errors have been identified. The changes defined within the qualifying comments will be implemented in future revisions of ISO 6336‑1, ISO 6336‑2, ISO 6336‑3 and ISO 6336‑5. No additional calculations are presented here that are outside of the referenced documents.

Eight worked examples are presented with the necessary input data for each gear set provided at the beginning of the calculation. Calculation details are presented in full for one worked example, with all following examples having summarized results data presented in tabular format.

For all calculations in this document, the flank tolerance classes according to ISO 1328‑1:2013 are applied.

PD ISO/TR 6336-30:2022

Calculation of load capacity of spur and helical gears - Calculation examples for the application of ISO 6336 parts 1,2,3,5

Current

Published:

31 Dec 2022