SIST ISO 4405:2023

Hydraulic fluid power - Fluid contamination - Determination of particulate contamination by the gravimetric method

This document defines the gravimetric method for determining the contamination level of fluids used in hydraulic fluid power systems.
The working instructions provided in this document serve for the gravimetric determination of dirt content of pressure fluids from mineral oil with additives. They are used in hydraulic systems with hydrostatic drive.

Transmissions hydrauliques - Pollution des fluides - Détermination de la pollution particulaire par la méthode gravimétrique

Le présent document définit une méthode gravimétrique de détermination du taux de pollution des fluides utilisés dans les systèmes de transmissions hydrauliques.
Les instructions de travail fournies dans ce document servent à la détermination gravimétrique de la teneur en particules des fluides sous pression à partir d'huile minérale complétée d’additifs utilisés dans les systèmes hydrauliques à entraînement hydrostatique.

Fluidna tehnika - Hidravlika - Onesnaženje fluidov - Ugotavljanje onesnaženosti z delci - Gravimetrijska metoda

General Information

• Status: Published
• Publication Date: 13-Mar-2023
• ICS: 23.100.60 - Filters, seals and contamination of fluids
• Technical Committee: IHPV - Hydraulics and pneumatics
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 06-Mar-2023
• Due Date: 11-May-2023
• Completion Date: 14-Mar-2023
• Ref Project: ISO 4405:2022 - Hydraulic fluid power — Fluid contamination — Determination of particulate contamination by the gravimetric method

Relations

• Revises: SIST ISO 4405:1997 - Hydraulic fluid power -- Fluid contamination -- Determination of particulate contamination by the gravimetric method
• Effective Date: 23-Apr-2020

Standards Content (Sample)

SLOVENSKI STANDARD
SIST ISO 4405:2023
01-april-2023

Fluidna tehnika - Hidravlika - Onesnaženje fluidov - Ugotavljanje onesnaženosti z

delci - Gravimetrijska metoda

Hydraulic fluid power - Fluid contamination - Determination of particulate contamination

by the gravimetric method

Transmissions hydrauliques - Pollution des fluides - Détermination de la pollution

particulaire par la méthode gravimétrique
Ta slovenski standard je istoveten z: ISO 4405:2022
ICS:
23.100.60 Filtri, tesnila in Filters, seals and
onesnaževanje tekočin contamination of fluids
SIST ISO 4405:2023 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------
SIST ISO 4405:2023
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SIST ISO 4405:2023
INTERNATIONAL ISO
STANDARD 4405
Second edition
2022-07
Hydraulic fluid power — Fluid
contamination — Determination of
particulate contamination by the
gravimetric method
Transmissions hydrauliques — Pollution des fluides — Détermination
de la pollution particulaire par la méthode gravimétrique
Reference number
ISO 4405:2022(E)
© ISO 2022
---------------------- Page: 3 ----------------------
SIST ISO 4405:2023
ISO 4405:2022(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2022

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]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
© ISO 2022 – All rights reserved
---------------------- Page: 4 ----------------------
SIST ISO 4405:2023
ISO 4405:2022(E)
Contents Page

Foreword ........................................................................................................................................................................................................................................iv

Introduction .................................................................................................................................................................................................................................v

1 Scope ................................................................................................................................................................................................................................. 1

2 Normative references ..................................................................................................................................................................................... 1

3 Terms and definitions .................................................................................................................................................................................... 1

4 Principle ........................................................................................................................................................................................................................ 2

5 Test apparatus ........................................................................................................................................................................................................2

5.1 Equipment ................................................................................................................................................................................................... 2

5.2 Filter membrane .................................................................................................................................................................................... 2

6 Rinsing and cleaning chemicals (Solvent) ................................................................................................................................ 3

7 Glassware cleaning procedure [determination of the cleanliness of the glass funnel

and the graduated cylinder at the beginning (blank value)] ......... ....................................................................... 3

8 Sampling ....................................................................................................................................................................................................................... 4

9 Conditioning and weighing the analysis membrane ..................................................................................................... 4

10 Blank test .....................................................................................................................................................................................................................4

11 Sample analysis .....................................................................................................................................................................................................5

12 Test result ...................................................................... .............................................................................................................................................. 5

13 Test repeatability ................................................................................................................................................................................................6

14 Identification statement (reference to this document) .............................................................................................. 6

Annex A (normative) Use of different solvent ............................................................................................................................................7

Annex B (normative) Data recording ..................................................................................................................................................................8

Annex C (informative) Photographs of the test equipment ......................................................................................................... 9

Bibliography .............................................................................................................................................................................................................................13

iii
© ISO 2022 – All rights reserved
---------------------- Page: 5 ----------------------
SIST ISO 4405:2023
ISO 4405:2022(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.

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 131, Fluid power systems, Subcommittee

SC 6, Contamination control.

This second edition cancels and replaces the first edition (ISO 4405:1991), which has been technically

revised.
The main changes are as follows.

— The calibration and test equipment have been updated and reduced to the most essential parts.

— The single steps of the calibration and test procedure have been updated and adapted to achieve the

most reliable and verifiable test results.

— The double-membrane method has been eliminated as the test results have proven to be less reliable

than those obtained by the single-membrane method.

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.
© ISO 2022 – All rights reserved
---------------------- Page: 6 ----------------------
SIST ISO 4405:2023
ISO 4405:2022(E)
Introduction

In hydraulic fluid power systems, power is transmitted and controlled through a liquid under pressure

within an enclosed circuit. The liquid is both a lubricant and a power-transmitting medium.

Reliable system performance requires control of the fluid medium. Qualitative and quantitative

determination of particulate contamination in the fluid medium requires precision in obtaining the

sample and in determining the nature and extent of contamination.

The gravimetric method of determination of fluid contamination involves weighing suspended solids

per unit volume of fluid. The method employs membrane filters, which maintain fluid cleanliness by

removing insoluble particles.
© ISO 2022 – All rights reserved
---------------------- Page: 7 ----------------------
SIST ISO 4405:2023
---------------------- Page: 8 ----------------------
SIST ISO 4405:2023
INTERNATIONAL STANDARD ISO 4405:2022(E)
Hydraulic fluid power — Fluid contamination —
Determination of particulate contamination by the
gravimetric method
1 Scope

This document defines the gravimetric method for determining the contamination level of fluids used

in hydraulic fluid power systems.

The working instructions provided in this document serve for the gravimetric determination of dirt

content of pressure fluids from mineral oil with additives. They are used in hydraulic systems with

hydrostatic drive.
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 4021, Hydraulic fluid power — Particulate contamination analysis — Extraction of fluid samples from

lines of an operating system
ISO 5598, Fluid power systems and components — Vocabulary

ISO 11158, Lubricants, industrial oils and related products (class L) — Family H (hydraulic systems) —

Specifications for categories HH, HL, HM, HV and HG
3 Terms and definitions

For the purposes of this document, the terms and definitions given in ISO 5598 and the following apply.

ISO and IEC maintain terminology databases for use in standardization at the following addresses:

— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
hydraulic oil HH
non-inhibited mineral oil
3.2
hydraulic oil HL
oil of HH type with improved anti-rust and anti-oxidation properties
3.3
hydraulic oil HM
oil of HL type with improved anti-wear and filterability properties
3.4
hydraulic oil HV
oil of HM type with improved viscosity/temperature properties
© ISO 2022 – All rights reserved
---------------------- Page: 9 ----------------------
SIST ISO 4405:2023
ISO 4405:2022(E)
3.5
hydraulic oil HG
oil of HM type with improved anti-stick-slip properties
4 Principle

The gravimetric amount of contamination shall be determined by filtering a defined volume of fluid

under vacuum conditions through one filter membrane. The increase in mass of the membrane

after filtration represents the solid impurity content. This analytical method is suitable for dirt

concentrations of 3 mg/l or greater and the hydraulic oils of categories: HH, HL, HM, HV, and HG, in

accordance with ISO 11158. The room conditions should have a temperature between 20 °C and 30 °C

and humidity between 30 % and 65 % relative humidity (RH).
5 Test apparatus
5.1 Equipment
1) One suction bottle made of glass.

2) Solvent dispenser rinsed and filled with filtered solvent - 0,2 µm (see Figure C.1).

3) PTFE seal (white) for stainless steel filter grid or glass frit (see Figure C.2).

4) Membrane holder funnel made of glass for the stainless steel filter grid (see Figure C.3).

5) Stainless steel filter grid or glass frit (see Figure C.4 or Figure C.5).
6) Glass funnel.

7) Metal spring clip with electrical grounding and glass funnel (see Figure C.6).

8) Petri dish made of glass with lid (see Figure C.7).
9) Watch glass made of glass; diameter approximately 60 mm (see Figure C.8).

10) Exsiccator/desiccator with silica gel drying agent (with colour indicator), to operate without

vacuum (see Figure C.9).
11) One 250 ml graduated cylinder for oil samples (see Figure C.10).
12) Vacuum pump with adjustable vacuum level.
13) Non-ventilated drying oven up to 100 °C.
14) Filter tweezers, stainless steel with smooth endings.
15) Solvent-proof gloves without powder inside.

16) Analytical balance (accuracy ±0,02 mg with five-digit display), the electrostatic conductivity

between the weighting plate and the grounding of the power plug shall be given.
...

INTERNATIONAL ISO
STANDARD 4405
Second edition
2022-07
Hydraulic fluid power — Fluid
contamination — Determination of
particulate contamination by the
gravimetric method
Transmissions hydrauliques — Pollution des fluides — Détermination
de la pollution particulaire par la méthode gravimétrique
Reference number
ISO 4405:2022(E)
© ISO 2022
---------------------- Page: 1 ----------------------
ISO 4405:2022(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2022

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]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
© ISO 2022 – All rights reserved
---------------------- Page: 2 ----------------------
ISO 4405:2022(E)
Contents Page

Foreword ........................................................................................................................................................................................................................................iv

Introduction .................................................................................................................................................................................................................................v

1 Scope ................................................................................................................................................................................................................................. 1

2 Normative references ..................................................................................................................................................................................... 1

3 Terms and definitions .................................................................................................................................................................................... 1

4 Principle ........................................................................................................................................................................................................................ 2

5 Test apparatus ........................................................................................................................................................................................................2

5.1 Equipment ................................................................................................................................................................................................... 2

5.2 Filter membrane .................................................................................................................................................................................... 2

6 Rinsing and cleaning chemicals (Solvent) ................................................................................................................................ 3

7 Glassware cleaning procedure [determination of the cleanliness of the glass funnel

and the graduated cylinder at the beginning (blank value)] ......... ....................................................................... 3

8 Sampling ....................................................................................................................................................................................................................... 4

9 Conditioning and weighing the analysis membrane ..................................................................................................... 4

10 Blank test .....................................................................................................................................................................................................................4

11 Sample analysis .....................................................................................................................................................................................................5

12 Test result ...................................................................... .............................................................................................................................................. 5

13 Test repeatability ................................................................................................................................................................................................6

14 Identification statement (reference to this document) .............................................................................................. 6

Annex A (normative) Use of different solvent ............................................................................................................................................7

Annex B (normative) Data recording ..................................................................................................................................................................8

Annex C (informative) Photographs of the test equipment ......................................................................................................... 9

Bibliography .............................................................................................................................................................................................................................13

iii
© ISO 2022 – All rights reserved
---------------------- Page: 3 ----------------------
ISO 4405:2022(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.

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 131, Fluid power systems, Subcommittee

SC 6, Contamination control.

This second edition cancels and replaces the first edition (ISO 4405:1991), which has been technically

revised.
The main changes are as follows.

— The calibration and test equipment have been updated and reduced to the most essential parts.

— The single steps of the calibration and test procedure have been updated and adapted to achieve the

most reliable and verifiable test results.

— The double-membrane method has been eliminated as the test results have proven to be less reliable

than those obtained by the single-membrane method.

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.
© ISO 2022 – All rights reserved
---------------------- Page: 4 ----------------------
ISO 4405:2022(E)
Introduction

In hydraulic fluid power systems, power is transmitted and controlled through a liquid under pressure

within an enclosed circuit. The liquid is both a lubricant and a power-transmitting medium.

Reliable system performance requires control of the fluid medium. Qualitative and quantitative

determination of particulate contamination in the fluid medium requires precision in obtaining the

sample and in determining the nature and extent of contamination.

The gravimetric method of determination of fluid contamination involves weighing suspended solids

per unit volume of fluid. The method employs membrane filters, which maintain fluid cleanliness by

removing insoluble particles.
© ISO 2022 – All rights reserved
---------------------- Page: 5 ----------------------
INTERNATIONAL STANDARD ISO 4405:2022(E)
Hydraulic fluid power — Fluid contamination —
Determination of particulate contamination by the
gravimetric method
1 Scope

This document defines the gravimetric method for determining the contamination level of fluids used

in hydraulic fluid power systems.

The working instructions provided in this document serve for the gravimetric determination of dirt

content of pressure fluids from mineral oil with additives. They are used in hydraulic systems with

hydrostatic drive.
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 4021, Hydraulic fluid power — Particulate contamination analysis — Extraction of fluid samples from

lines of an operating system
ISO 5598, Fluid power systems and components — Vocabulary

ISO 11158, Lubricants, industrial oils and related products (class L) — Family H (hydraulic systems) —

Specifications for categories HH, HL, HM, HV and HG
3 Terms and definitions

For the purposes of this document, the terms and definitions given in ISO 5598 and the following apply.

ISO and IEC maintain terminology databases for use in standardization at the following addresses:

— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
hydraulic oil HH
non-inhibited mineral oil
3.2
hydraulic oil HL
oil of HH type with improved anti-rust and anti-oxidation properties
3.3
hydraulic oil HM
oil of HL type with improved anti-wear and filterability properties
3.4
hydraulic oil HV
oil of HM type with improved viscosity/temperature properties
© ISO 2022 – All rights reserved
---------------------- Page: 6 ----------------------
ISO 4405:2022(E)
3.5
hydraulic oil HG
oil of HM type with improved anti-stick-slip properties
4 Principle

The gravimetric amount of contamination shall be determined by filtering a defined volume of fluid

under vacuum conditions through one filter membrane. The increase in mass of the membrane

after filtration represents the solid impurity content. This analytical method is suitable for dirt

concentrations of 3 mg/l or greater and the hydraulic oils of categories: HH, HL, HM, HV, and HG, in

accordance with ISO 11158. The room conditions should have a temperature between 20 °C and 30 °C

and humidity between 30 % and 65 % relative humidity (RH).
5 Test apparatus
5.1 Equipment
1) One suction bottle made of glass.

2) Solvent dispenser rinsed and filled with filtered solvent - 0,2 µm (see Figure C.1).

3) PTFE seal (white) for stainless steel filter grid or glass frit (see Figure C.2).

4) Membrane holder funnel made of glass for the stainless steel filter grid (see Figure C.3).

5) Stainless steel filter grid or glass frit (see Figure C.4 or Figure C.5).
6) Glass funnel.

7) Metal spring clip with electrical grounding and glass funnel (see Figure C.6).

8) Petri dish made of glass with lid (see Figure C.7).
9) Watch glass made of glass; diameter approximately 60 mm (see Figure C.8).

10) Exsiccator/desiccator with silica gel drying agent (with colour indicator), to operate without

vacuum (see Figure C.9).
11) One 250 ml graduated cylinder for oil samples (see Figure C.10).
12) Vacuum pump with adjustable vacuum level.
13) Non-ventilated drying oven up to 100 °C.
14) Filter tweezers, stainless steel with smooth endings.
15) Solvent-proof gloves without powder inside.

16) Analytical balance (accuracy ±0,02 mg with five-digit display), the electrostatic conductivity

between the weighting plate and the grounding of the power plug shall be given.
17) Clock accurate to the second.
For photos and description of the test equipment, see Annex C.
5.2 Filter membrane

Filter membranes, of 47 mm diameter, white, non-gridded 0,8 µm pore size and compatible with

the fluid to be analysed and with the rinsing chemicals can be used. Reference membranes have a

0,8 µm pore size. The material shall be made of cellulose acetate, for example, cellulose mixed ester

© ISO 2022 – All rights reserved
---------------------- Page: 7 ----
...

NORME ISO
INTERNATIONALE 4405
Deuxième édition
2022-07
Transmissions hydrauliques —
Pollution des fluides — Détermination
de la pollution particulaire par la
méthode gravimétrique
Hydraulic fluid power — Fluid contamination — Determination of
particulate contamination by the gravimetric method
Numéro de référence
ISO 4405:2022(F)
© ISO 2022
---------------------- Page: 1 ----------------------
ISO 4405:2022(F)
DOCUMENT PROTÉGÉ PAR COPYRIGHT
© ISO 2022

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]
E-mail: [e-mail]
Web: www.iso.org
Publié en Suisse
© ISO 2022 – Tous droits réservés
---------------------- Page: 2 ----------------------
ISO 4405:2022(F)
Sommaire Page

Avant-propos .............................................................................................................................................................................................................................iv

Introduction .................................................................................................................................................................................................................................v

1 Domaine d’application ................................................................................................................................................................................... 1

2 Références normatives ..................................................................................................................................................................................1

3 Termes et définitions ...................................................................................................................................................................................... 1

4 Principe.......................................................................................................................................................................................................................... 2

5 Appareillage d'essai..........................................................................................................................................................................................2

5.1 Matériel ......................................................................................................................................................................................................... 2

5.2 Membrane filtrante ............................................................................................................................................................................ 3

6 Produits chimiques de rinçage et de nettoyage (solvant) ....................................................................................... 3

7 Mode opératoire de nettoyage de la verrerie [détermination de la propreté initiale

de l’entonnoir en verre et de l’éprouvette graduée (valeur à blanc)] ..........................................................3

8 Échantillonnage ....................................................................................................................................................................................................4

9 Conditionnement et pesée de la membrane d’analyse ................................................................................................ 4

10 Essai à blanc .............................................................................................................................................................................................................. 5

11 Analyse de l’échantillon ...............................................................................................................................................................................5

12 Résultats d’essai ................................................................................................................................................................................................... 6

13 Répétabilité de l’essai ..................................................................................................................................................................................... 6

14 Phrase d'identification (référence au présent document) ...................................................................................... 6

Annexe A (normative) Utilisation d’un solvant différent .............................................................................................................. 7

Annexe B (normative) Enregistrement des données ......................................................................................................................... 8

Annexe C (informative) Photographies de l’équipement d’essai............................................................................................ 9

Bibliographie ...........................................................................................................................................................................................................................13

iii
© ISO 2022 – Tous droits réservés
---------------------- Page: 3 ----------------------
ISO 4405:2022(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 (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 www.iso.org/avant-propos.

Le présent document a été élaboré par le comité technique ISO/TC 131, Transmissions hydrauliques et

pneumatiques, sous-comité SC 6, Contrôle de la contamination.

Cette deuxième édition annule et remplace la première édition (ISO 4405:1991) qui a fait l'objet d'une

révision technique.
Les principales modifications sont les suivantes :

— les parties sur l’étalonnage et l’équipement d’essai ont été mises à jour et réduites à l’essentiel ;

— les étapes du mode opératoire d’étalonnage et d’essai ont été mises à jour et adaptées d'obtenir les

résultats d’essai les plus fiables et les plus vérifiables ;

— la méthode à double membrane a été éliminée car elle produisait des résultats d’essai qui ne se sont

pas révélés aussi fiables que ceux obtenus via la méthode à une seule membrane.

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.
© ISO 2022 – Tous droits réservés
---------------------- Page: 4 ----------------------
ISO 4405:2022(F)
Introduction

Dans les systèmes de transmissions hydrauliques, l’énergie est transmise et commandée par un

liquide sous pression circulant en circuit fermé. Le liquide sert à la fois de lubrifiant et de moyen de

transmission de l’énergie.

La fiabilité de fonctionnement du système exige un contrôle du fluide. Pour déterminer quantitativement

et qualitativement la pollution particulaire du fluide, il est nécessaire de garantir la fidélité du

prélèvement de l’échantillon et de la détermination de la nature et de l’ampleur de la pollution.

La méthode gravimétrique de détermination de la pollution du fluide procède par pesage des solides en

suspension par unité de volume de fluide. Cette méthode utilise à cet effet des filtres à membrane qui

conservent au fluide sa propreté en éliminant les polluants insolubles.
© ISO 2022 – Tous droits réservés
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NORME INTERNATIONALE ISO 4405:2022(F)
Transmissions hydrauliques — Pollution des fluides —
Détermination de la pollution particulaire par la méthode
gravimétrique
1 Domaine d’application

Le présent document définit une méthode gravimétrique de détermination du taux de pollution des

fluides utilisés dans les systèmes de transmissions hydrauliques.

Les instructions de travail fournies dans ce document servent à la détermination gravimétrique de la

teneur en particules des fluides sous pression à partir d'huile minérale complétée d’additifs utilisés

dans les systèmes hydrauliques à entraînement hydrostatique.
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 4021, Transmissions hydrauliques — Analyse de la pollution par particules — Prélèvement des

échantillons de fluide dans les circuits en fonctionnement
ISO 5598, Transmissions hydrauliques et pneumatiques — Vocabulaire

ISO 11158, Lubrifiants, huiles industrielles et produits connexes (classe L) — Famille H (systèmes

hydrauliques) — Spécifications des catégories HH, HL, HM, HV et HG
3 Termes et définitions

Pour les besoins du présent document, les termes et définitions de l’ISO 5598 ainsi que les suivants

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 https:// www .iso .org/ obp

— IEC Electropedia : disponible à l'adresse https:// www .electropedia .org/
3.1
huile hydraulique HH
huile minérale non inhibée
3.2
huile hydraulique HL
huile de type HH aux propriétés antirouille et anti-oxydation améliorées
3.3
huile hydraulique HM
huile de type HL aux propriétés anti-usure et de filtrabilité améliorées
© ISO 2022 – Tous droits réservés
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ISO 4405:2022(F)
3.4
huile hydraulique HV
huile de type HM aux propriétés de viscosité/température améliorées
3.5
huile hydraulique HG
huile de type HM aux propriétés antidérapantes améliorées
4 Principe

L’ampleur de la pollution gravimétrique doit être déterminée en filtrant un volume défini de fluide

sous vide à travers une membrane filtrante. L’augmentation de masse de la membrane après la

filtration correspond à la teneur en impuretés solides. Cette méthode d’analyse est appropriée pour

les concentrations en particules de 3 mg/l ou plus, et pour les huiles hydrauliques de catégories HH,

HL, HM, HV et HG, conformément à l’ISO 11158. Il convient que les conditions ambiantes soient une

température comprise entre 20 °C et 30 °C et une humidité relative (HR) comprise entre 30 % et 65 %.

5 Appareillage d'essai
5.1 Matériel
1) Fiole à vide en verre.

2) Distributeur de solvant, rincé et rempli de solvant filtré à 0,2 µm (voir Figure C.1).

3) Joint en PTFE (blanc) pour support membrane grillagé en acier inoxydable ou verre fritté

(voir Figure C.2).

4) Entonnoir porte-membrane en verre pour le support membrane grillagé en acier inoxydable

(voir Figure C.3).

5) Support membrane grillagé en acier inoxydable ou verre fritté (voir Figure C.4 ou Figure C.5).

6) Entonnoir en verre.

7) Pince métallique à ressort et mise à la terre électrique et entonnoir en verre (voir Figure C.6).

8) Boîte de Petri en verre avec son couvercle (voir Figure C.7).
9) Verre de montre en verre, d’un diamètre d’environ 60 mm (voir Figure C.8).

10) Dessiccateur à agent déshydratant en gel de silice (avec indicateur coloré), pour utilisation sans

vide (voir Figure C.9).

11) Éprouvette graduée de 250 ml pour les échantillons d’huile (voir Figure C.10).

12) Pompe à vide à dépression réglable.
13) Étuve de séchage non ventilée pouvant chauffer jusqu’à 100 °C.
14) Pinces à filtres, en acier inoxydable et à bouts lisses.
15) Gants non poudrés et résistants au solvant.

16) Balance analytique (d’une exactitude de ±0,02 mg et avec un affichage à 5 chiffres) dont la

conductivité électrostatique entre son plateau et la mise à la terre de son cordon d’alimentation

doit être donnée.
17) Horloge exacte à la seconde.

Des photos et des descriptions de l’appareillage d’essai sont données à l’Annexe C.

© ISO 2022 – Tous droits réservés
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ISO 4405:2022(F)
5.2 Membrane filtrante

Des membranes filtrantes de 47 mm de diamètre, blanches non quadrillées, de 0,8 µm de porosité, et

compatibles avec le fluide à analyser et les produits chimiques de rinçage peuvent être utilisées. Les

membranes de référence ont une porosité de 0,8 µm. Leur matériau constitutif doit être de l’acétate

de cellulose, par exemple : la membrane en ester de cellulose de 0,8 µm de porosité de Millipore

(Type AAWP04700), la membrane Pall (Type GN4-08 µm Metricel MCE) ou la membrane Sartorius

(no
...