NF ISO 6336-2

NF ISO 6336-2

April 2020
Standard Current

Calculation of load capacity of spur and helical gears - Part 2 : calculation of surface durability (pitting)

This document specifies the fundamental formulae for use in the determination of the surface load capacity of cylindrical gears with involute external or internal teeth. It includes formulae for all influences on surface durability for which quantitative assessments can be made. It applies primarily to oil‑lubricated transmissions, but can also be used to obtain approximate values for (slow‑running) grease‑lubricated transmissions, as long as sufficient lubricant is present in the mesh at all times. The given formulae are valid for cylindrical gears with tooth profiles in accordance with the basic rack standardized in ISO 53. They can also be used for teeth conjugate to other basic racks where the actual transverse contact ratio is less than εαn = 2,5. The results are in good agreement with other methods (see References [5], [7], [10], [12]). These formulae cannot be directly applied for the assessment of types of gear tooth surface damage such as plastic yielding, scratching, scuffing and so on, other than that described in Clause 4. The load capacity determined by way of the permissible contact stress is called the "surface load capacity" or "surface durability". If this scope does not apply, refer to ISO 6336-1:2019, Clause 4.

View the extract
Main informations

Collections

National standards and national normative documents

Publication date

April 2020

Number of pages

45 p.

Reference

NF ISO 6336-2

ICS Codes

21.200   Gears

Classification index

E23-030-2

Print number

2 - 01/12/2020

International kinship

Sumary
Calculation of load capacity of spur and helical gears - Part 2 : calculation of surface durability (pitting)

This document specifies the fundamental formulae for use in the determination of the surface load capacity of cylindrical gears with involute external or internal teeth. It includes formulae for all influences on surface durability for which quantitative assessments can be made. It applies primarily to oil‑lubricated transmissions, but can also be used to obtain approximate values for (slow‑running) grease‑lubricated transmissions, as long as sufficient lubricant is present in the mesh at all times.

The given formulae are valid for cylindrical gears with tooth profiles in accordance with the basic rack standardized in ISO 53. They can also be used for teeth conjugate to other basic racks where the actual transverse contact ratio is less than εαn = 2,5. The results are in good agreement with other methods (see References [5], [7], [10], [12]).

These formulae cannot be directly applied for the assessment of types of gear tooth surface damage such as plastic yielding, scratching, scuffing and so on, other than that described in Clause 4.

The load capacity determined by way of the permissible contact stress is called the "surface load capacity" or "surface durability".

If this scope does not apply, refer to ISO 6336-1:2019, Clause 4.

Replaced standards (1)
NF ISO 6336-2
October 2006
Standard Cancelled
Calculation of load capacity of spur and helical gears - Part 2 : calculation of surface durability (pitting)

Le présent document fait partie d'un ensemble de normes sur le calcul de la capacité de charge des roues cylindriques à denture intérieure ou extérieure et à profil en développante de cercle. Le présent document donne les formules de base à utiliser pour déterminer la résistance à la pression de contact. La pression de Hertz, indicateur significatif de la pression de contact, est l'hypothèse utilisée dans ces calculs. Cependant d'autres facteurs d'influence sont pris en compte, quand une évaluation qualitative de ces derniers est possible.

Table of contents
View the extract
  • 1 Domaine d'application
  • 2 Références normatives
  • 3 Termes, définitions, symboles et termes abrégés
  • 4 Endommagement par écaillages et coefficients de sécurité
  • 5 Formules de base
  • 6 Facteur géométrique, Z H, et facteurs de contact, Z B et Z D
  • 7 Facteur d'élasticité, Z E
  • 8 Facteur de rapport de conduite, Ze
  • 9 Facteur d'angle d'hélice, Zß
  • 10 Tenue en fatigue à la pression de contact
  • 11 Facteur de durée de vie, Z NT (pour les flancs)
  • 12 Influences du film lubrifiant, facteurs Z L, Z v et Z R
  • 13 Facteur d'écrouissage, Z W
  • 14 Facteur de dimension, Z
    X
  • Bibliographie
ZOOM ON ... the Requirements department
To comply with a standard, you need to quickly understand its issues in order to determine its impact on your activity.

The Requirements department helps you quickly locate within the normative text:
- mandatory clauses to satisfy,
- non-essential but useful clauses to know, such as permissions and recommendations.

The identification of these types of clauses is based on the document “ISO / IEC Directives, Part 2 - Principles and rules of structure and drafting of ISO documents ”as well as on a constantly enriched list of verbal forms.

With Requirements, quickly access the main part of the normative text!

With Requirements, quickly access the main part of the normative text!
What is the Redline format?
The Redline + service - standards comparator allows you to easily and simply identify major changes between the current standard and its last canceled version.

At a glance, you will be able to identify the additions, deletions or modifications to a text, table, figure and formula.
At a glance, you will be able to identify the additions, deletions or modifications to a text, table, figure and formula

The Redlines + service is offered to you on the collection of French standards in force, in French language and in HTML and PDF format.

For an overview of the service, click on View a standard in redline format
Need to identify, monitor and decipher standards?

COBAZ is the simple and effective solution to meet the normative needs related to your activity, in France and abroad.

Available by subscription, CObaz is THE modular solution to compose according to your needs today and tomorrow. Quickly discover CObaz!

Request your free, no-obligation live demo

I discover COBAZ