ISO 7902-3:1998

Hydrodynamic plain journal bearings under steady-state conditions — Circular cylindrical bearings — Part 3: Permissible operational parameters

Paliers lisses hydrodynamiques radiaux fonctionnant en régime stabilisé — Paliers circulaires cylindriques — Partie 3: Paramètres opérationnels admissibles

Hidrodinamični radialni drsni ležaji za neprekinjeno obratovanje - Valjasti ležaji - 3. del: Dopustni obratovalni parametri

General Information

• Status: Withdrawn
• Publication Date: 01-Jul-1998
• Withdrawal Date: 01-Jul-1998
• ICS: 21.100.10 - Plain bearings
• Technical Committee: ISO/TC 123/SC 8 - Calculation methods for plain bearings and their applications
• Drafting Committee: ISO/TC 123/SC 8 - Calculation methods for plain bearings and their applications
• Current Stage: 9599 - Withdrawal of International Standard
• Completion Date: 09-Jun-2020
• Ref Project: SIST ISO 7902-3:2002 - Hydrodynamic plain journal bearings under steady-state conditions -- Circular cylindrical bearings -- Part 3: Permissible operational parameters

Relations

• Revised: ISO 7902-3:2020 - Hydrodynamic plain journal bearings under steady-state conditions — Circular cylindrical bearings — Part 3: Permissible operational parameters
• Effective Date: 23-Apr-2020

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 7902-3
First edition
1998-07-01
Hydrodynamic plain journal bearings under
steady-state conditions — Circular
cylindrical bearings —
Part 3:
Permissible operational parameters
Paliers lisses hydrodynamiques radiaux fonctionnant en régime stabilisé —
Paliers circulaires cylindriques —
Partie 3: Paramètres opérationnels admissibles
A
Reference number
ISO 7902-3:1998(E)

---------------------- Page: 1 ----------------------
ISO 7902-3:1998(E)
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.
Draft International Standards adopted by the technical committees are
circulated to the member bodies for voting. Publication as an International
Standard requires approval by at least 75 % of the member bodies casting
a vote.
International Standard ISO 7902-3 was prepared by Technical Committee
ISO/TC 123, Plain bearings, Subcommittee SC 4, Methods of calculation of
plain bearings.
ISO 7902 consists of the following parts, under the general title
Hydrodynamic plain journal bearings under steady-state conditions —
Circular cylindrical bearings:
— Part 1: Calculation procedure
— Part 2: Functions used in the calculation procedure
— Part 3: Permissible operational parameters
Annex A of this part of ISO 7902 is for information only.
©  ISO 1998
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced
or utilized in any form or by any means, electronic or mechanical, including photocopying and
microfilm, without permission in writing from the publisher.
International Organization for Standardization
Case postale 56 • CH-1211 Genève 20 • Switzerland
Internet [e-mail]
X.400 c=ch; a=400net; p=iso; o=isocs; s=central
Printed in Switzerland
ii

---------------------- Page: 2 ----------------------
©
ISO ISO 7902-3:1998(E)
Introduction
In order to attain sufficient operational reliability of circular cylindrical plain
journal bearings when calculated in accordance with ISO 7902-1, it is
essential that the calculated operational parameters h , T or T and p
min B ex
do not lie above or below the permissible operational parameters h ,
lim
T and p . The permissible parameters represent geometrically and
lim
lim
technologically dependent operational limits within the plain bearing
tribological system. They are empirical values which still enable sufficient
operational reliability even for minor influences (see ISO 7902-1).
iii

---------------------- Page: 3 ----------------------
©
INTERNATIONAL STANDARD  ISO ISO 7902-3:1998(E)
Hydrodynamic plain journal bearings under steady-state
conditions — Circular cylindrical bearings —
Part 3:
Permissible operational parameters
1  Scope
This part of ISO 7902 specifies empirical permissible values for , and .
h T p
lim lim
lim
The empirical values stated can be modified for certain applications, for example if information supplied by the
manufacturer is to be taken into account. The descriptions of the symbols and calculation examples are given in
ISO 7902-1.
2  Normative reference
The following standard contains provisions which, through reference in this text, constitute provisions of this part of
ISO 7902. At the time of publication, the edition indicated was valid. All standards are subject to revision, and
parties to agreements based on this part of ISO 7902 are encouraged to investigate the possibility of applying the
most recent edition of the standard indicated below. Members of IEC and ISO maintain registers of currently valid
International Standards.
ISO 7902-1:1998, Hydrodynamic plain journal bearings under steady-state conditions — Circular cylindrical
bearings — Part 1: Calculation procedure.
3  Operational parameters to avoid wear
3.1  The aim of keeping above the minimum permissible lubrication film thickness h is to retain complete
lim
lubrication of the plain bearing in order to attain least possible wear and low susceptibility to faults. The lubricant
should be free of contaminating particles, otherwise increased wear, scoring and local overheating can result, thus
impairing correct functioning of the plain bearing. If necessary, appropriate filtering of the lubricant should be
provided for.
3.2  The minimum permissible lubrication film thickness h , as a characteristic parameter for the transition to
lim
mixed friction (see ISO 7902-1:1998, 6.6), can be determined from the following equation:
1 1
hR=+z Rz+By+y+h . . . (1)
lim BJ wav,eff
2 2
1

---------------------- Page: 4 ----------------------
©
ISO
ISO 7902-3:1998(E)
This takes into account
— the sum of the mean peak-to-valley heights of bearing and shaft at the ideal location (line X-X) [Rz + Rz ]
B J
— the misalignment (line Y-Y) within the bearing length [1/2 ]
By
— the mean deflection (line Z-Z) [1/2 y]
3.3  If wavy geometrical deviations occur in the sliding surfaces (bearing or shaft) in the circumferential direction,
they are taken into account during the determination of h by the effective waviness h for the most
lim wav,eff
unfavourable shaft position. In this case, h is the effective waviness of the bearing under static loading or the
wav,eff
effective waviness of the shaft under rotating loading, respectively.
The effective waviness h and the maximum permissible effective waviness h at a given operating
wav,eff wav,eff,lim
point (e or h ) can be determined using figure 2 if roughnesses, deformations and tilt positions are known.
lim
3.4  In accordance with equation (1), the following applies:
h = m + h
lim wav,eff
where
1 1
mR=+z Rz+ By+ y
BJ
2 2
E
h =a
wav,eff
G
With a given minimum lubricant film thickness h the maximum permissible effective waviness amplitude is
min
determined from
h = h - m
wav,eff,lim min
The maximum permissible absolute waviness, h , is determined from
wav,eff,lim
G
h = h
wav,lim wav,eff,lim
E
3.5  An example of the determination of h , h , h and h (from figure 2) is as follows.
wav,eff lim wav,eff,lim wav,lim
Given quantities:
B/D = 0,5
-6
C/2 = 85 · 10 m
-6
= 6 10 m
m ·
-6
h = 5 · 10 m
wav
i = 6
-6
h = 8,5 · 10 m
min
h
min
e=−1 = 09,
C2
2

---------------------- Page: 5 ----------------------
©
ISO
ISO 7902-3:1998(E)
With B/D = 0,5, figure 2 gives E = 0,86.
With i = 6 and e = 0,9, figure 2 gives G = 1,85.
Hence
0,86
−−66
h =× 5× 10 m= 2,32× 10 m
wav,eff
1,85
and
−−66 -6
h =×6 10 m+ 2,32× 10 m = 8,32× 10 m
lim
-
6
Since h > h , h = 8,5 · 10 m is permissible.
min lim min
−−66 −6
h =×8,5 10 m−6× 10 m=×2,5 10 m
wav,eff,lim
1,85
−−66
h =×23,,5×10m=58×10m
wav,lim
0,86
3.6  In general, deviations of form are irregular. For the determination of h , the waves in the sliding surface
wav,eff
area under load are significant.
For running-in processes under low load and sliding velocity, it is possible to allow a lower minimum film thickness
owing to the smoothing and adjusting of the sliding surfaces. If necessary, a bearing material having a good
running-in ability shall be used.
Table 1 gives empirical permissible values for h , in which a mean peak-to-valley height of Rz < 4 mm for the
lim J
shaft, minor geometrical errors of the sliding surfaces, careful assembly and adequate filtering of the lubricant are
assumed.
Fi
...

SLOVENSKI STANDARD
SIST ISO 7902-3:2002
01-marec-2002
+LGURGLQDPLþQLUDGLDOQLGUVQLOHåDML]DQHSUHNLQMHQRREUDWRYDQMH9DOMDVWLOHåDML
GHO'RSXVWQLREUDWRYDOQLSDUDPHWUL
Hydrodynamic plain journal bearings under steady-state conditions -- Circular cylindrical
bearings -- Part 3: Permissible operational parameters
Paliers lisses hydrodynamiques radiaux fonctionnant en régime stabilisé -- Paliers
circulaires cylindriques -- Partie 3: Paramètres opérationnels admissibles
Ta slovenski standard je istoveten z: ISO 7902-3:1998
ICS:
21.100.10 Drsni ležaji Plain bearings
SIST ISO 7902-3:2002 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------

SIST ISO 7902-3:2002

---------------------- Page: 2 ----------------------

SIST ISO 7902-3:2002
INTERNATIONAL ISO
STANDARD 7902-3
First edition
1998-07-01
Hydrodynamic plain journal bearings under
steady-state conditions — Circular
cylindrical bearings —
Part 3:
Permissible operational parameters
Paliers lisses hydrodynamiques radiaux fonctionnant en régime stabilisé —
Paliers circulaires cylindriques —
Partie 3: Paramètres opérationnels admissibles
A
Reference number
ISO 7902-3:1998(E)

---------------------- Page: 3 ----------------------

SIST ISO 7902-3:2002
ISO 7902-3:1998(E)
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.
Draft International Standards adopted by the technical committees are
circulated to the member bodies for voting. Publication as an International
Standard requires approval by at least 75 % of the member bodies casting
a vote.
International Standard ISO 7902-3 was prepared by Technical Committee
ISO/TC 123, Plain bearings, Subcommittee SC 4, Methods of calculation of
plain bearings.
ISO 7902 consists of the following parts, under the general title
Hydrodynamic plain journal bearings under steady-state conditions —
Circular cylindrical bearings:
— Part 1: Calculation procedure
— Part 2: Functions used in the calculation procedure
— Part 3: Permissible operational parameters
Annex A of this part of ISO 7902 is for information only.
©  ISO 1998
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced
or utilized in any form or by any means, electronic or mechanical, including photocopying and
microfilm, without permission in writing from the publisher.
International Organization for Standardization
Case postale 56 • CH-1211 Genève 20 • Switzerland
Internet [e-mail]
X.400 c=ch; a=400net; p=iso; o=isocs; s=central
Printed in Switzerland
ii

---------------------- Page: 4 ----------------------

SIST ISO 7902-3:2002
©
ISO ISO 7902-3:1998(E)
Introduction
In order to attain sufficient operational reliability of circular cylindrical plain
journal bearings when calculated in accordance with ISO 7902-1, it is
essential that the calculated operational parameters h , T or T and p
min B ex
do not lie above or below the permissible operational parameters h ,
lim
T and p . The permissible parameters represent geometrically and
lim
lim
technologically dependent operational limits within the plain bearing
tribological system. They are empirical values which still enable sufficient
operational reliability even for minor influences (see ISO 7902-1).
iii

---------------------- Page: 5 ----------------------

SIST ISO 7902-3:2002

---------------------- Page: 6 ----------------------

SIST ISO 7902-3:2002
©
INTERNATIONAL STANDARD  ISO ISO 7902-3:1998(E)
Hydrodynamic plain journal bearings under steady-state
conditions — Circular cylindrical bearings —
Part 3:
Permissible operational parameters
1  Scope
This part of ISO 7902 specifies empirical permissible values for , and .
h T p
lim lim
lim
The empirical values stated can be modified for certain applications, for example if information supplied by the
manufacturer is to be taken into account. The descriptions of the symbols and calculation examples are given in
ISO 7902-1.
2  Normative reference
The following standard contains provisions which, through reference in this text, constitute provisions of this part of
ISO 7902. At the time of publication, the edition indicated was valid. All standards are subject to revision, and
parties to agreements based on this part of ISO 7902 are encouraged to investigate the possibility of applying the
most recent edition of the standard indicated below. Members of IEC and ISO maintain registers of currently valid
International Standards.
ISO 7902-1:1998, Hydrodynamic plain journal bearings under steady-state conditions — Circular cylindrical
bearings — Part 1: Calculation procedure.
3  Operational parameters to avoid wear
3.1  The aim of keeping above the minimum permissible lubrication film thickness h is to retain complete
lim
lubrication of the plain bearing in order to attain least possible wear and low susceptibility to faults. The lubricant
should be free of contaminating particles, otherwise increased wear, scoring and local overheating can result, thus
impairing correct functioning of the plain bearing. If necessary, appropriate filtering of the lubricant should be
provided for.
3.2  The minimum permissible lubrication film thickness h , as a characteristic parameter for the transition to
lim
mixed friction (see ISO 7902-1:1998, 6.6), can be determined from the following equation:
1 1
hR=+z Rz+By+y+h . . . (1)
lim BJ wav,eff
2 2
1

---------------------- Page: 7 ----------------------

SIST ISO 7902-3:2002
©
ISO
ISO 7902-3:1998(E)
This takes into account
— the sum of the mean peak-to-valley heights of bearing and shaft at the ideal location (line X-X) [Rz + Rz ]
B J
— the misalignment (line Y-Y) within the bearing length [1/2 ]
By
— the mean deflection (line Z-Z) [1/2 y]
3.3  If wavy geometrical deviations occur in the sliding surfaces (bearing or shaft) in the circumferential direction,
they are taken into account during the determination of h by the effective waviness h for the most
lim wav,eff
unfavourable shaft position. In this case, h is the effective waviness of the bearing under static loading or the
wav,eff
effective waviness of the shaft under rotating loading, respectively.
The effective waviness h and the maximum permissible effective waviness h at a given operating
wav,eff wav,eff,lim
point (e or h ) can be determined using figure 2 if roughnesses, deformations and tilt positions are known.
lim
3.4  In accordance with equation (1), the following applies:
h = m + h
lim wav,eff
where
1 1
mR=+z Rz+ By+ y
BJ
2 2
E
h =a
wav,eff
G
With a given minimum lubricant film thickness h the maximum permissible effective waviness amplitude is
min
determined from
h = h - m
wav,eff,lim min
The maximum permissible absolute waviness, h , is determined from
wav,eff,lim
G
h = h
wav,lim wav,eff,lim
E
3.5  An example of the determination of h , h , h and h (from figure 2) is as follows.
wav,eff lim wav,eff,lim wav,lim
Given quantities:
B/D = 0,5
-6
C/2 = 85 · 10 m
-6
= 6 10 m
m ·
-6
h = 5 · 10 m
wav
i = 6
-6
h = 8,5 · 10 m
min
h
min
e=−1 = 09,
C2
2

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SIST ISO 7902-3:2002
©
ISO
ISO 7902-3:1998(E)
With B/D = 0,5, figure 2 gives E = 0,86.
With i = 6 and e = 0,9, figure 2 gives G = 1,85.
Hence
0,86
−−66
h =× 5× 10 m= 2,32× 10 m
wav,eff
1,85
and
−−66 -6
h =×6 10 m+ 2,32× 10 m = 8,32× 10 m
lim
-
6
Since h > h , h = 8,5 · 10 m is permissible.
min lim min
−−66 −6
h =×8,5 10 m−6× 10 m=×2,5 10 m
wav,eff,lim
1,85
−−66
h =×23,,5×10m=58×10m
wav,lim
0,86
3.6  In general, deviations of form are irregular. For the determination of h , the waves i
...

NORME ISO
INTERNATIONALE 7902-3
Première édition
1998-07-01
Paliers lisses hydrodynamiques radiaux
fonctionnant en régime stabilisé — Paliers
circulaires cylindriques —
Partie 3:
Paramètres opérationnels admissibles
Hydrodynamic plain journal bearings under steady-state conditions —
Circular cylindrical bearings —
Part 3: Permissible operational parameters
A
Numéro de référence
ISO 7902-3:1998(F)

---------------------- Page: 1 ----------------------
ISO 7902-3:1998(F)
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 (CEI) en
ce qui concerne la normalisation électrotechnique.
Les projets de Normes internationales adoptés par les comités techniques
sont soumis aux comités membres pour vote. Leur publication comme
Normes internationales requiert l'approbation de 75 % au moins des
comités membres votants.
La Norme internationale ISO 7902-3 a été élaborée par le comité technique
ISO/TC 123, Paliers lisses, sous-comité SC 4, Méthodes de calcul des
paliers lisses.
L'ISO 7902 comprend les parties suivantes, présentées sous le titre
général Paliers lisses hydrodynamiques radiaux fonctionnant en régime
stabilisé — Paliers circulaires cylindriques:
— Partie 1: Méthode de calcul
— Partie 2: Fonctions utilisées pour le calcul
— Partie 3: Paramètres opérationnels admissibles
L'annexe A de la présente partie de l'ISO 7902 est donnée uniquement à
titre d'information.
©  ISO 1998
Droits de reproduction réservés. Sauf prescription différente, aucune partie de cette publi-
cation ne peut être reproduite ni utilisée sous quelque forme que ce soit et par aucun pro-
cédé, électronique ou mécanique, y compris la photocopie et les microfilms, sans l'accord
écrit de l'éditeur.
Organisation internationale de normalisation
Case postale 56 • CH-1211 Genève 20 • Suisse
Internet [e-mail]
X.400 c=ch; a=400net; p=iso; o=isocs; s=central
Imprimé en Suisse
ii

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©
ISO ISO 7902-3:1998(F)
Introduction
Pour assurer une bonne fiabilité opérationnelle des paliers lisses circulaires
cylindriques calculés conformément à l'ISO 7902-1, il est essentiel que les
paramètres opérationnels calculés h , T ou T et p ne se situent pas
min B ex
au-dessus ou au-dessous des limites opérationnelles admissibles h ,
lim
et . Les paramètres admissibles représentent les limites de
T p
lim
lim
fonctionnement dépendant de la géométrie et du régime des paliers à
l'intérieur du système tribologique qu'ils constituent. Ce sont des valeurs
empiriques qui garantissent une fiabilité suffisante même en cas de
perturbations mineures (voir ISO 7902-1).
iii

---------------------- Page: 3 ----------------------
©
NORME INTERNATIONALE  ISO ISO 7902-3:1998(F)
Paliers lisses hydrodynamiques radiaux fonctionnant en régime
stabilisé — Paliers circulaires cylindriques —
Partie 3:
Paramètres opérationnels admissibles
1  Domaine d'application
La présente partie de l'ISO 7902 prescrit les valeurs empiriques admissibles de , et .
h T p
lim lim
lim
Les valeurs empiriques indiquées peuvent être modifiées dans certains cas particuliers, notamment s'il faut tenir
compte des informations fournies par le fabricant. La description des symboles et les exemples de calcul figurent
dans l'ISO 7902-1.
2  Référence normative
La norme suivante contient des dispositions qui, par suite de la référence qui en est faite, constituent des
dispositions valables pour la présente partie de l'ISO 7902. Au moment de la publication, l'édition indiquée était en
vigueur. Toute norme est sujette à révision et les parties prenantes des accords fondés sur la présente partie de
l'ISO 7902 sont invitées à rechercher la possibilité d'appliquer l'édition la plus récente de la norme indiquée
ci-après. Les membres de la CEI et de l'ISO possèdent le registre des Normes internationales en vigueur
à un moment donné.
ISO 7902-1:1998, Paliers lisses hydrodynamiques radiaux fonctionnant en régime stabilisé — Paliers circulaires
cylindriques — Partie 1: Méthode de calcul.
3  Paramètres opérationnels évitant l'usure
3.1  Maintenir au-dessous des limites fixées l'épaisseur minimale admissible de la pellicule lubrifiante, h , permet
lim
d'assurer une bonne lubrification du palier lisse tout en diminuant au maximum l'usure possible et la tendance aux
défauts. Il convient que le lubrifiant soit exempt de particules polluantes contribuant à user le palier, le rayer ou y
engendrer des surchauffes localisées, et entraînant une dégradation de son fonctionnement. Il convient donc, si
nécessaire, de le filtrer.
3.2  L'épaisseur minimale admissible de la pellicule lubrifiante [paramètre caractéristique de la transition vers
h
lim
un régime mixte (voir ISO 7902-1:1998, 6.6)] peut se déterminer à l'aide de l'équation suivante:
1 1
hR=+z Rz+By+y+h . . . (1)
lim BJ wav,eff
2 2
1

---------------------- Page: 4 ----------------------
©
ISO
ISO 7902-3:1998(F)
Cette formule tient compte
— de la somme des hauteurs moyennes de crête à creux du palier et de l'arbre à l'endroit idéal (ligne X-X)
[Rz + Rz ]
B J
— du défaut d'alignement (ligne Y-Y) sur la largeur du palier [1/2 By]
— de la flèche moyenne (ligne Z-Z) [1/2 y]
3.3  Si des ondulations géométriques s'observent sur les surfaces de frottement (palier ou arbre) dans le sens
circonférentiel, il convient d'en tenir compte dans la détermination de h en introduisant dans l'équation l'ondulation
lim
utile h pour la position d'arbre la plus défavorable. Dans ce cas, h correspond soit à l'ondulation utile du
wav,eff wav,eff
palier sous charge statique, soit à l'ondulation utile de l'arbre sous charge tournante.
On peut déterminer l'ondulation utile h et l'ondulation utile maximale admissible h en un point de
wav,eff wav,eff,lim
fonctionnement donné (e ou h ) en utilisant la figure 2 si l'on connaît la rugosité, la déformation et l'inclinaison.
lim
3.4  Selon l'équation (1), on a
h = m + h
lim wav,eff
où
1 1
mR=+z Rz+ By+ y
BJ
2 2
E
h =a
wav,eff
G
Pour une épaisseur minimale donnée de pellicule lubrifiante h , l'amplitude de l'ondulation utile maximale
min
admissible est
=
h h - m
wav,eff,lim min
L'ondulation absolue maximale admissible, h , est déterminée par
wav,eff,lim
G
h = h
wav,lim wav,eff,lim
E
3.5  Un exemple de détermination de h , h , h et h selon la figure 2 est comme suit.
wav,eff lim wav,eff,lim wav,lim
Soit
B/D = 0,5
-6
C/2 = 85 · 10 m
-6
m = 6 · 10 m
-6
h = 5 · 10 m
wav
i = 6
-6
h = 8,5 · 10 m
min
h
min
e=−1 = 09,
C2
2

---------------------- Page: 5 ----------------------
©
ISO
ISO 7902-3:1998(F)
Avec B/D = 0,5, la figure 2 donne E = 0,86.
Avec i = 6 et e = 0,9, la figure 2 donne G = 1,85.
Donc
0,86
−−66
h =× 5× 10 m= 2,32× 10 m
wav,eff
1,85
et
−−66 −6
h =×6 10 m+ 2,32× 10 m = 8,32× 10 m
lim
-6
Puisque h > h , h = 8,5 · 10 m est admissible.
min lim min
−−66 −6
h =×8,5 10 m−6× 10 m = 2,5× 10 m
wav,eff,lim
1,85
−−66
h =×23,,5×10m=58×10m
wav,lim
0,86
3.6  En général, les écarts de forme sont irréguliers. Pour déterminer h , les ondulations de la surface de
wav,eff
glissement sous charge sont significatives.
Pour procéder au rodage à faible vitesse de glissement et sous charge peu élevée, il est possible d'avoir une
épaisseur minimale de pellicule lubrifiante plus faible du fait du lissage et de l'ajustement des surfaces de
glissement. Si besoin est, on peut avoir recours à un matériau antifriction d'une bonne aptitude au rodage.
Le tableau 1 donne les valeurs empiriques admissibles de h , compte tenu de valeurs moyennes de hauteur crête
lim
à creux Rz < 4 mm pour l'arbre, d'erreurs géométriques mineures dans les surfaces de glissement, d'un montage
J
soigneux et d'une filtration appropriée du lubrifiant.
...