ISO 6336-6:2019

Calculation of load capacity of spur and helical gears — Part 6: Calculation of service life under variable load

This document specifies the information and standardized conditions necessary for the calculation of the service life (or safety factors for a required life) of gears subject to variable loading for only pitting and tooth root bending strength. If this scope does not apply, refer ISO 6336-1:2019, Clause 4.

Calcul de la capacité de charge des engrenages cylindriques à dentures droite et hélicoïdale — Partie 6: Calcul de la durée de vie en service sous charge variable

Le présent document spécifie les informations et normalise les conditions de calcul de la durée de vie en service (ou des coefficients de sécurité pour une durée de vie exigée) d'engrenages soumis à des conditions de chargement variables, uniquement vis-à-vis de la tenue en fatigue à l'écaillage et la tenue en fatigue en flexion en pied de dent. Si le domaine d'application ne s'applique pas, se référer à l'ISO 6336‑1:2019, Article 4.

Izračun nosilnosti ravnozobih in poševnozobih zobnikov - 6. del: Izračun dobe trajanja pri spremenljivi obremenitvi

General Information

• Status: Published
• Publication Date: 25-Nov-2019
• ICS: 21.200 - Gears
• Technical Committee: ISO/TC 60/SC 2 - Gear capacity calculation
• Drafting Committee: ISO/TC 60/SC 2/WG 6 - Gear calculations
• Current Stage: 9093 - International Standard confirmed
• Start Date: 22-Apr-2025
• Completion Date: 26-Apr-2025
• Ref Project: SIST ISO 6336-6:2020 - Calculation of load capacity of spur and helical gears - Part 6: Calculation of service life under variable load

Relations

• Revises: ISO 6336-6:2006 - Calculation of load capacity of spur and helical gears — Part 6: Calculation of service life under variable load
• Effective Date: 13-Apr-2013
• Revises: ISO 6336-6:2006/Cor 1:2007 - Calculation of load capacity of spur and helical gears — Part 6: Calculation of service life under variable load — Technical Corrigendum 1
• Effective Date: 13-Apr-2013

Standards Content (Sample)

SLOVENSKI STANDARD
01-oktober-2020
Izračun nosilnosti ravnozobih in poševnozobih zobnikov - 6. del: Izračun dobe
trajanja pri spremenljivi obremenitvi
Calculation of load capacity of spur and helical gears - Part 6: Calculation of service life
under variable load
Calcul de la capacité de charge des engrenages cylindriques à dentures droite et
hélicoïdale
Ta slovenski standard je istoveten z: ISO 6336-6:2019
ICS:
21.200 Gonila Gears
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

INTERNATIONAL ISO
STANDARD 6336-6
Second edition
2019-11
Calculation of load capacity of spur
and helical gears —
Part 6:
Calculation of service life under
variable load
Calcul de la capacité de charge des engrenages cylindriques à
dentures droite et hélicoïdale —
Partie 6: Calcul de la durée de vie en service sous charge variable
Reference number
©
ISO 2019
© ISO 2019
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting
on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address
below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Fax: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii © ISO 2019 – All rights reserved

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms, definitions, symbols and abbreviated terms . 1
3.1 Terms and definitions . 1
3.2 Symbols and abbreviated terms. 1
4 General . 5
4.1 Determination of load and stress spectra . 5
4.2 General calculation of service life . 7
4.3 Palmgren-Miner rule . 8
5 Calculation of service strength on the basis of single-stage strength according to
ISO 6336 series . 9
5.1 Basic principles. 9
5.2 Calculation of stress spectra .13
5.3 Determination of pitting and bending strength values .14
5.4 Determination of safety factors .14
Annex A (normative) Determination of application factor, K , from given load spectrum
A
using equivalent torque, T .16
eq
Annex B (informative) Equivalent cumulative damage .22
Annex C (informative) Example calculation for safety factor from given load spectrum .30
Bibliography .37
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/ patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see www .iso .org/
iso/ foreword .html.
This document was prepared by Technical Committee ISO/TC 60, Gears, Subcommittee SC 2, Gear
capacity calculation.
This second edition cancels and replaces the first edition (ISO 6336-6:2006), which has been technically
revised. It also incorporates the Technical Corrigendum ISO 6336-6:2006/Cor.1:2007.
The main changes compared to the previous edition are as follows:
— in Annex A, examples have been revised;
— integration of Annex B "Equivalent cumulative damage".
A list of all parts in the ISO 6336 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www .iso .org/ members .html.
iv © ISO 2019 – All rights reserved

Introduction
ISO 6336 (all parts) 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.
— Technical Specifications (TS) contain calculation methods that are still subject to further
development.
— Technical Reports (TR) contain data that is informative, such as example calculations.
The procedures specified in parts 1 to 19 of the ISO 6336 series cover fatigue analyses for gear rating.
The procedures described in parts 20 to 29 of the ISO 6336 series are predominantly related to the
tribological behavior of the lubricated flank surface contact. Parts 30 to 39 of the ISO 6336 series
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 the ISO 6336 series without referring to specific
parts requires the use of only those parts that are currently designated as International Standards (see
Table 1 for listing). When requesting further calculations, the relevant part or parts of the ISO 6336
series need to be specified. Use of a Technical Specification as acceptance criteria for a specific design
need to be agreed in advance between the manufacturer and the purchaser.
Table 1 — Parts of the ISO 6336 series (STATUS AS OF DATE OF PUBLICATION)
Technical
International Technical
Calculation of load capacity of spur and helical gears Specifica-
Standard Report
tion
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 (also applicable to bevel
and hypoid gears) — Flash temperature method
X
(replaces: ISO/TR 13989-1)
Part 21: Calculation of scuffing load capacity (also applicable to bevel
and hypoid gears) — Integral temperature method
X
(replaces: ISO/TR 13989-2)
Part 22: Calculation of micropitting load capacity
X
(replaces: ISO/TR 15144-1)
Part 30: Calculation examples for the application of ISO 6336-1, 2, 3, 5 X
Part 31: Calculation examples of micropitting load capacity
X
(replaces: ISO/TR 15144-2)
INTERNATIONAL STANDARD ISO 6336-6:2019(E)
Calculation of load capacity of spur and helical gears —
Part 6:
Calculation of service life under variable load
1 Scope
This document specifies the information and standardized conditions necessary for the calculation of
the service life (or safety factors for a required life) of gears subject to variable loading for only pitting
and tooth root bending strength.
If this scope does not apply, refer ISO 6336-1:2019, Clause 4.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 1122-1:1998, Vocabulary of gear terms — Part 1: Definitions related to geometry
ISO 6336-1, Calculation of load capacity of spur and helical gears —Part 1: Basic principles, introduction
and general influence factors
ISO 6336-2, Calculation of load capacity of spur and helical gears — Part 2: Calculation of surface durability
(pitting)
ISO 6336-3, Calculation of load capacity of spur and helical gears — Part 3: Calculation of tooth bending
strength
3 Terms, definitions, symbols and abbreviated terms
3.1 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 6336-1 and ISO 1122-1:1998
apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at http:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
3.2 Symbols and abbreviated terms
For the purposes of this document, the symbols and abbreviated terms given in ISO 6336-1,
ISO 1122-1:1998 and Table 2 apply.
Table 2 — Symbols and abbreviated terms used in this document
Abbreviated terms
Term Description
Eh material designation for case-hardened wrought steel
GG material designation for grey cast iron
GGG material designation for nodular cast iron (perlitic, bainitic, ferritic structure)
GTS material designation for black malleable cast iron (perlitic structure)
IF material designation for flame or induction hardened wrought special steel
NT material designation for nitrided wrought steel, nitriding steel
NV material designation for through-hardened wrought steel, nitrided, nitrocarburized
St material designation for normalized base steel (σ < 800 N/mm )
B
V material designation for through-hardened wrought special steel, alloy or carbon (σ ≥ 800 N/mm )
B
Symbols
Symbol Description Unit
a
a centre distance mm
b face width mm
a
d diameter (without subscript, reference diameter ) mm
a
d tip diameter mm
a
F force or load N
F (nominal) transverse tangential load at reference cylinder per mesh N
t
K constant, factors concerning tooth load —
K application factor (Annex A shall apply for pitting and tooth root bending) —
A
K transverse load factor (bending) —
Fα
K face load factor (bending) —
Fβ
K transvers
...

INTERNATIONAL ISO
STANDARD 6336-6
Second edition
2019-11
Calculation of load capacity of spur
and helical gears —
Part 6:
Calculation of service life under
variable load
Calcul de la capacité de charge des engrenages cylindriques à
dentures droite et hélicoïdale —
Partie 6: Calcul de la durée de vie en service sous charge variable
Reference number
©
ISO 2019
© ISO 2019
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting
on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address
below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Fax: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii © ISO 2019 – All rights reserved

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms, definitions, symbols and abbreviated terms . 1
3.1 Terms and definitions . 1
3.2 Symbols and abbreviated terms. 1
4 General . 5
4.1 Determination of load and stress spectra . 5
4.2 General calculation of service life . 7
4.3 Palmgren-Miner rule . 8
5 Calculation of service strength on the basis of single-stage strength according to
ISO 6336 series . 9
5.1 Basic principles. 9
5.2 Calculation of stress spectra .13
5.3 Determination of pitting and bending strength values .14
5.4 Determination of safety factors .14
Annex A (normative) Determination of application factor, K , from given load spectrum
A
using equivalent torque, T .16
eq
Annex B (informative) Equivalent cumulative damage .22
Annex C (informative) Example calculation for safety factor from given load spectrum .30
Bibliography .37
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/ patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see www .iso .org/
iso/ foreword .html.
This document was prepared by Technical Committee ISO/TC 60, Gears, Subcommittee SC 2, Gear
capacity calculation.
This second edition cancels and replaces the first edition (ISO 6336-6:2006), which has been technically
revised. It also incorporates the Technical Corrigendum ISO 6336-6:2006/Cor.1:2007.
The main changes compared to the previous edition are as follows:
— in Annex A, examples have been revised;
— integration of Annex B "Equivalent cumulative damage".
A list of all parts in the ISO 6336 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www .iso .org/ members .html.
iv © ISO 2019 – All rights reserved

Introduction
ISO 6336 (all parts) 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.
— Technical Specifications (TS) contain calculation methods that are still subject to further
development.
— Technical Reports (TR) contain data that is informative, such as example calculations.
The procedures specified in parts 1 to 19 of the ISO 6336 series cover fatigue analyses for gear rating.
The procedures described in parts 20 to 29 of the ISO 6336 series are predominantly related to the
tribological behavior of the lubricated flank surface contact. Parts 30 to 39 of the ISO 6336 series
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 the ISO 6336 series without referring to specific
parts requires the use of only those parts that are currently designated as International Standards (see
Table 1 for listing). When requesting further calculations, the relevant part or parts of the ISO 6336
series need to be specified. Use of a Technical Specification as acceptance criteria for a specific design
need to be agreed in advance between the manufacturer and the purchaser.
Table 1 — Parts of the ISO 6336 series (STATUS AS OF DATE OF PUBLICATION)
Technical
International Technical
Calculation of load capacity of spur and helical gears Specifica-
Standard Report
tion
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 (also applicable to bevel
and hypoid gears) — Flash temperature method
X
(replaces: ISO/TR 13989-1)
Part 21: Calculation of scuffing load capacity (also applicable to bevel
and hypoid gears) — Integral temperature method
X
(replaces: ISO/TR 13989-2)
Part 22: Calculation of micropitting load capacity
X
(replaces: ISO/TR 15144-1)
Part 30: Calculation examples for the application of ISO 6336-1, 2, 3, 5 X
Part 31: Calculation examples of micropitting load capacity
X
(replaces: ISO/TR 15144-2)
INTERNATIONAL STANDARD ISO 6336-6:2019(E)
Calculation of load capacity of spur and helical gears —
Part 6:
Calculation of service life under variable load
1 Scope
This document specifies the information and standardized conditions necessary for the calculation of
the service life (or safety factors for a required life) of gears subject to variable loading for only pitting
and tooth root bending strength.
If this scope does not apply, refer ISO 6336-1:2019, Clause 4.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 1122-1:1998, Vocabulary of gear terms — Part 1: Definitions related to geometry
ISO 6336-1, Calculation of load capacity of spur and helical gears —Part 1: Basic principles, introduction
and general influence factors
ISO 6336-2, Calculation of load capacity of spur and helical gears — Part 2: Calculation of surface durability
(pitting)
ISO 6336-3, Calculation of load capacity of spur and helical gears — Part 3: Calculation of tooth bending
strength
3 Terms, definitions, symbols and abbreviated terms
3.1 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 6336-1 and ISO 1122-1:1998
apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at http:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
3.2 Symbols and abbreviated terms
For the purposes of this document, the symbols and abbreviated terms given in ISO 6336-1,
ISO 1122-1:1998 and Table 2 apply.
Table 2 — Symbols and abbreviated terms used in this document
Abbreviated terms
Term Description
Eh material designation for case-hardened wrought steel
GG material designation for grey cast iron
GGG material designation for nodular cast iron (perlitic, bainitic, ferritic structure)
GTS material designation for black malleable cast iron (perlitic structure)
IF material designation for flame or induction hardened wrought special steel
NT material designation for nitrided wrought steel, nitriding steel
NV material designation for through-hardened wrought steel, nitrided, nitrocarburized
St material designation for normalized base steel (σ < 800 N/mm )
B
V material designation for through-hardened wrought special steel, alloy or carbon (σ ≥ 800 N/mm )
B
Symbols
Symbol Description Unit
a
a centre distance mm
b face width mm
a
d diameter (without subscript, reference diameter ) mm
a
d tip diameter mm
a
F force or load N
F (nominal) transverse tangential load at reference cylinder per mesh N
t
K constant, factors concerning tooth load —
K application factor (Annex A shall apply for pitting and tooth root bending) —
A
K transverse load factor (bending) —
Fα
K face load factor (bending) —
Fβ
K transverse load factor (contact stress) —
Hα
K face load factor (contact stress) —
Hβ
K mesh load factor —
γ
K dynamic factor —
v
m normal module mm
n
N number of load cycles —
N number of load cycles to failure for bin i —
i
N number of load cycles of S-N curve —
L
N number of load cycles for bending damage —
LF
a
For external gears a, d, d , z and z are positive; for internal gearing, a, d, d and z have a negative sign, z has a
a 1 2 a 2 1
positive sign. All calculated diameters have a negative sign for internal gearing.
2 © ISO 2019 – All rights reserved

Table 2 (continued)
Symbols
Symbol Description Unit
N number of load cycles for pitting damage —
LH
N number of load cycles for endurance limit —
L ref
n number of load cycles for the equivalent damage fatigue curve (Annex B) —
D,i
number of load cycles for the equivalent damage fatigue curve (reference)
n —
D,REF
(Annex B
...

NORME ISO
INTERNATIONALE 6336-6
Deuxième édition
2019-11
Calcul de la capacité de charge des
engrenages cylindriques à dentures
droite et hélicoïdale —
Partie 6:
Calcul de la durée de vie en service
sous charge variable
Calculation of load capacity of spur and helical gears —
Part 6: Calculation of service life under variable load
Numéro de référence
©
ISO 2019
DOCUMENT PROTÉGÉ PAR COPYRIGHT
© ISO 2019
Tous droits réservés. Sauf prescription différente ou nécessité dans le contexte de sa mise en œuvre, aucune partie de cette
publication ne peut être reproduite ni utilisée sous quelque forme que ce soit et par aucun procédé, électronique ou mécanique,
y compris la photocopie, ou la diffusion sur l’internet ou sur un intranet, sans autorisation écrite préalable. Une autorisation peut
être demandée à l’ISO à l’adresse ci-après ou au comité membre de l’ISO dans le pays du demandeur.
ISO copyright office
Case postale 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Genève
Tél.: [phone]
Fax: [phone]
E-mail: [e-mail]
Web: www.iso.org
Publié en Suisse
ii © ISO 2019 – Tous droits réservés

Sommaire Page
Avant-propos .iv
Introduction .v
1 Domaine d'application . 1
2 Références normatives . 1
3 Termes, définitions, symboles et termes abrégés . 1
3.1 Termes et définitions . 1
3.2 Symboles et termes abrégés . 1
4 Généralités . 5
4.1 Détermination des spectres de charge et de contrainte. 5
4.2 Calcul général de la durée en service. 8
4.3 Règle de Palmgren-Miner . 9
5 Calcul de la tenue en service sur la base d’un simple étage de réduction
conformément à la série ISO 6336 .10
5.1 Principes de base .10
5.2 Calcul des spectres de contrainte.14
5.3 Détermination des valeurs de la tenue à l’écaillage et à la flexion .15
5.4 Détermination des facteurs de sécurité .15
Annexe A (normative) Détermination du facteur d’application, K , à partir d’un spectre de
A
charge utilisant la couple équivalent, T .17
eq
Annexe B (informative) Endommagement cumulés équivalents .23
Annexe C (informative) Exemple de calcul de coefficient de sécurité à partir d’un spectre
de charge donné .32
Bibliographie .39
Avant-propos
L'ISO (Organisation internationale de normalisation) est une fédération mondiale d'organismes
nationaux de normalisation (comités membres de l'ISO). L'élaboration des Normes internationales est
en général confiée aux comités techniques de l'ISO. Chaque comité membre intéressé par une étude
a le droit de faire partie du comité technique créé à cet effet. Les organisations internationales,
gouvernementales et non gouvernementales, en liaison avec l'ISO participent également aux travaux.
L'ISO collabore étroitement avec la Commission électrotechnique internationale (IEC) en ce qui
concerne la normalisation électrotechnique.
Les procédures utilisées pour élaborer le présent document et celles destinées à sa mise à jour sont
décrites dans les Directives ISO/IEC, Partie 1. Il convient, en particulier de prendre note des différents
critères d'approbation requis pour les différents types de documents ISO. Le présent document a été
rédigé conformément aux règles de rédaction données dans les Directives ISO/IEC, Partie 2 (voir www
.iso .org/ directives).
L'attention est attirée sur le fait que certains des éléments du présent document peuvent faire l'objet de
droits de propriété intellectuelle ou de droits analogues. L'ISO ne saurait être tenue pour responsable
de ne pas avoir identifié de tels droits de propriété et averti de leur existence. Les détails concernant
les références aux droits de propriété intellectuelle ou autres droits analogues identifiés lors de
l'élaboration du document sont indiqués dans l'Introduction et/ou dans la liste des déclarations de
brevets reçues par l'ISO (voir www .iso .org/ brevets).
Les appellations commerciales éventuellement mentionnées dans le présent document sont données
pour information, par souci de commodité, à l’intention des utilisateurs et ne sauraient constituer un
engagement.
Pour une explication de la nature volontaire des normes, la signification des termes et expressions
spécifiques de l'ISO liés à l'évaluation de la conformité, ou pour toute information au sujet de l'adhésion
de l'ISO aux principes de l’Organisation mondiale du commerce (OMC) concernant les obstacles
techniques au commerce (OTC), voir le lien suivant: www .iso .org/ iso/ fr/ avant -propos .html.
Le présent document a été élaboré par le comité technique ISO/TC 60, Engrenages, sous-comité SC 2,
Calcul de la capacité des engrenages.
Cette deuxième édition annule et remplace la première édition (ISO 6336-6:2006), qui a fait l’objet d’une
révision technique. Le rectificatif technique ISO 6336-6:2006/Cor.1:2007 est incorporé.
Les principales modifications par rapport à l’édition précédente sont les suivantes:
— révision des exemples de l'Annexe A;
— intégration de l'Annexe B «Détérioration cumulée équivalente».
Une liste de toutes les parties de la série ISO 6336 se trouve sur le site Web de l’ISO.
Il convient que l’utilisateur adresse tout retour d’information ou toute question concernant le présent
document à l’organisme national de normalisation de son pays. Une liste exhaustive desdits organismes
se trouve à l’adresse www .iso .org/ fr/ members .html.
iv © ISO 2019 – Tous droits réservés

Introduction
L’ISO 6336 (toutes les parties) est constituée de Normes internationales, de Spécifications techniques
(TS) et de Rapports techniques (TR) regroupés sous le titre général Calcul de la capacité de charge des
engrenages cylindriques à dentures droite et hélicoïdale (voir Tableau 1).
— Les Normes internationales contiennent des méthodes de calcul qui sont basées sur des pratiques
largement acceptées et qui ont été validées.
— Les Spécifications techniques (TS) contiennent des méthodes de calcul qui sont toujours en cours de
développement.
— Les Rapports techniques (TR) contiennent des données informatives, telles que des exemples de
calculs.
Les modes opératoires spécifiés dans les parties 1 à 19 de la série ISO 6336 traitent des analyses de
la fatigue pour l’évaluation de la tenue en fatigue des engrenages. Les modes opératoires décrits dans
les parties 20 à 29 de la série ISO 6336 sont principalement associés au comportement tribologique
du contact de surface des flancs de denture lubrifiée. Les parties 30 à 39 de la série ISO 6336 incluent
des exemples de calcul. La série ISO 6336 permet d’ajouter de nouvelles parties sous des numéros
appropriés, afin d’intégrer les connaissances acquises ultérieurement.
Toute demande de calculs selon la série ISO 6336 sans référence à des parties spécifiques nécessite
d'utiliser uniquement les parties désignées comme Normes internationales (voir la liste du Tableau 1).
Si des calculs supplémentaires sont requis, la ou les partie(s) pertinente(s) de la série ISO 6336 doivent
être spécifiées. L’utilisation d’une Spécification technique en tant que critère d’acceptation pour une
conception spécifique est soumise à un accord commercial.
Tableau 1 — Parties de la série ISO 6336 (STATUT À LA DATE DE PUBLICATION)
Calcul de la capacité de charge des engrenages Norme Spécification Rapport
cylindriques à dentures droite et hélicoïdale internationale technique technique
Partie 1: Principes de base, introduction et facteurs généraux
X
d’influence
Partie 2: Calcul de la résistance à la tenue en fatigue à la pression
X
de contact (écaillage)
Partie 3: Calcul de la tenue en fatigue à la flexion en pied de dent X
Partie 4: Calcul de la capacité de charge en rupture de flanc des dents X
Partie 5: Résistance et qualité des matériaux X
Partie 6: Calcul de la durée de vie en service sous charge variable X
Partie 20: Calcul de la capacité de charge au grippage (applicable
également aux engrenages coniques et hypoïdes) — Méthode de
X
la température éclair
(remplace: ISO/TR 13989-1)
Partie 21: Calcul de la capacité de charge au grippage (applicable
également aux engrenages coniques et hypoïdes) — Méthode de
X
la température intégrale
(Remplace: ISO/TR 13989-2)
Partie 22: Calcul de la capacité de charge aux micropiqûres
X
(remplace: ISO/TR 15144-1)
Partie 30: Exemples d’application de l’ISO 6336 Parties 1, 2, 3, 5 X
Partie 31: Exemples de calcul de la capacité de charge aux
micropiqûres
X
(Remplace: ISO/TR 15144-2)
vi © ISO 2019 – Tous droits réservés

NORME INTERNATIONALE ISO 6336-6:2019(F)
Calcul de la capacité de charge des engrenages
cylindriques à dentures droite et hélicoïdale —
Partie 6:
Calcul de la durée de vie en service sous charge variable
1 Domaine d'application
Le présent document spécifie les informations et normalise les conditions de calcul de la durée de vie
en service (ou des coefficients de sécurité pour une durée de vie exigée) d’engrenages soumis à des
conditions de chargement variables, uniquement vis-à-vis de la tenue en fatigue à l’écaillage et la tenue
en fatigue en flexion en pied de dent.
Si le domaine d’application ne s’applique pas, se référer à l’ISO 6336-1:2019, Article 4.
2 Références normatives
Les documents suivants sont cités dans le texte de sorte qu’ils constituent, pour tout ou partie de leur
contenu, des exigences du présent document. Pour les références datées, seule l’édition citée s’applique.
Pour les références non datées, la dernière édition du document de référence s'applique (y compris les
éventuels amendements).
ISO 1122-1:1998, Vocabulaire des engrenages — Partie 1: Définitions géométriques
ISO 6336-1, Calcul de la capacité de charge des engrenages cylindriques à dentures droite et hélicoïdale —
Partie 1: Principes de base, introduction et facteurs généraux d’influence
ISO 6336-2, Calcul de la capacité de charge des engrenages cylindriques à dentures droite et hélicoïdale —
Partie 2: Calcul de la tenue en fatigue à la pression de contact (écaillage)
ISO 6336-3, Calcul de la capacité de charge des engrenages cylindriques à dentures droite et hélicoïdale —
Partie 3: Calcul de la tenue en fatigue à la flexion en pied de dent
3 Termes, définitions, symboles et termes abrégés
3.1 Termes et définitions
Pour les besoins du présent document, les termes et les définitions donnés dans l’ISO 6336-1 et
l’ISO 1122-1:1998 s’appliquent.
L’ISO et l’IEC tiennent à jour des bases de données terminologiques destinées à être utilisées en
normalisation, consultables aux adresses suivantes:
— ISO Online browsing platform: disponible à l’adresse http:// www .iso .org/ obp
— IEC Electropedia: disponible à l’adresse http:// www .electropedia .org/
3.2 Symboles et termes abrégés
Pour les besoins du présent document, les symboles et termes abrégés donnés dans les ISO 6336-1,
ISO 1122-1:1998 et au Tableau 2 s’appliquent.
Tableau 2 — Symboles et termes abrégés utilisés dans le présent document
Abréviations
Terme Description
Eh appellation matière pour les aciers forgés, cémentés trempés et revenus
GG appellation matière pour les fontes grises
GGG appellation matière pour les fontes ductiles (structure perlitique, bainitique, ferritique)
GTS appellation matière pour les fontes malléables (structure perlitique)
IF appellation matière pour les aciers forgés, durcis superficiellement par trempe après chauffage
à la flamme ou par induction
N
...