ISO/DIS 6358-4.2

DRAFT INTERNATIONAL STANDARD ISO/DIS 6358-4.2
ISO/TC 131/SC 5 Secretariat: AFNOR
Voting begins on: Voting terminates on:
2009-10-29 2009-12-29

INTERNATIONAL ORGANIZATION FOR STANDARDIZATION • МЕЖДУНАРОДНАЯ ОРГАНИЗАЦИЯ ПО СТАНДАРТИЗАЦИИ • ORGANISATION INTERNATIONALE DE NORMALISATION

Transmissions pneumatiques — Détermination des caractéristiques de débit des éléments traversés par un

To expedite distribution, this document is circulated as received from the committee secretariat.

ISO Central Secretariat work of editing and text composition will be undertaken at publication

Pour accélérer la distribution, le présent document est distribué tel qu'il est parvenu du

secrétariat du comité. Le travail de rédaction et de composition de texte sera effectué au

THIS DOCUMENT IS A DRAFT CIRCULATED FOR COMMENT AND APPROVAL. IT IS THEREFORE SUBJECT TO CHANGE AND MAY NOT BE

IN ADDITION TO THEIR EVALUATION AS BEING ACCEPTABLE FOR INDUSTRIAL, TECHNOLOGICAL, COMMERCIAL AND USER PURPOSES, DRAFT

INTERNATIONAL STANDARDS MAY ON OCCASION HAVE TO BE CONSIDERED IN THE LIGHT OF THEIR POTENTIAL TO BECOME STANDARDS TO

RECIPIENTS OF THIS DRAFT ARE INVITED TO SUBMIT, WITH THEIR COMMENTS, NOTIFICATION OF ANY RELEVANT PATENT RIGHTS OF WHICH

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This ISO document is a Draft International Standard and is copyright-protected by ISO. Except as permitted

under the applicable laws of the user's country, neither this ISO draft nor any extract from it may be

reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, photocopying,

Requests for permission to reproduce should be addressed to either ISO at the address below or ISO's

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

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

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

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

3 Terms and definitions ...........................................................................................................................2

4 Symbols and units.................................................................................................................................2

5 Test installation .....................................................................................................................................2

5.1 Test circuit .............................................................................................................................................2

5.2 General requirements ...........................................................................................................................3

5.3 Requirements for the tank (item 4)......................................................................................................3

5.4 Special requirements ............................................................................................................................4

6 Test procedures.....................................................................................................................................4

6.1 Test conditions......................................................................................................................................4

6.1.1 Gas supply .............................................................................................................................................4

6.1.2 Checks....................................................................................................................................................4

6.1.3 Test measurements...............................................................................................................................4

6.2 Measuring procedures..........................................................................................................................5

6.3 Calculation of characteristics ..............................................................................................................6

6.3.1 Sonic conductance, C...........................................................................................................................6

6.3.2 Critical back-pressure ratio, b, and subsonic index, m.....................................................................7

7 Presentation of test results ..................................................................................................................7

8 Identification statement ........................................................................................................................8

Annex A (normative) Errors and classes of measurement accuracy.........................................................9

A.1 Classes of measurement accuracy .....................................................................................................9

A.2 Errors......................................................................................................................................................9

A.3 Combination of errors...........................................................................................................................9

A.4 Expected variations...............................................................................................................................9

Annex B (informative) Equations for calculation of flow-rate characteristics ........................................10

B.1 Calculation model................................................................................................................................10

B.2 Calculation of conductance, C ..........................................................................................................10

B.3 Calculation of critical back-pressure ratio, b, and subsonic index, m ..........................................11

Annex C (informative) Procedures for calculating critical back-pressure ratio, b, and subsonic

index, m, by the least-square method using the Solver function in Microsoft Excel ..................12

C.1 Using data in the subsonic region.....................................................................................................12

C.2 Using the Solver function built in Microsoft Excel ..........................................................................13

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.

International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.

The main task of technical committees is to prepare International Standards. 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.

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.

ISO 6358-4 was prepared by Technical Committee ISO/TC 131, Fluid power systems, Subcommittee SC 5,

ISO 6358 consists of the following parts, under the general title Pneumatic fluid power — Determination of

Many components that make up a pneumatic circuit operate under conditions of choked flow. In recognition

of this, ISO 6358:1989 defined test methods covering the whole range of flow from choked flow to subsonic

flow and the definition of two characteristics parameters, sonic conductance, C, and critical pressure ratio, b.

However, since the size of the pressure-measuring tubes connected upstream and downstream were the

same as the connecting ports of the component under test, it was not possible to measure the flow-rate

characteristics under stagnation condition, and also when components with large flow capacity were used, it

was not possible to achieve choked flow for measurement. Furthermore, it was revealed that for some

components, the flow-rate characteristics should not be approximated only with the characteristics parameters

This Internal Standard improves the above-mentioned shortcomings regarding measurement by using a

pressure-measuring tube whose internal diameter is larger than the connecting port of the component under

test. At the same time, it defines a characteristic equation, to which new characteristic parameters subsonic

index, m, and cracking pressure, Δp , have been added, in order to accurately indicate the flow-rate

This part of ISO 6358 defines a charge test to determine the flow-rate characteristics of pneumatic

components as an alternate to the test method specified in ISO 6358-2. This alternate test method tests a

component by charging the atmospheric air to a tank which has already been evacuated. This method allows

the determination of sonic conductance, C, critical back-pressure ratio, b, and subsonic index, m, of the

The charge test method specified in this part of ISO 6358 has the following advantages over the test method

This part of specifies charge test as an alternate test method for testing pneumatic fluid power components

that use compressible fluids, i.e. gases. It specifies requirements for the test installation, the test procedure

Accuracy of measurements is divided into two classes (A and B), which are explained in Annex A. Guidance

on the equation for calculation of characteristics is given in Annex B. Guidance on the procedures for

This part of ISO 6358 applies to the following components with inlet and outlet ports:

NOTE This part of ISO 6358 can be applied to the components listed in item d) with limitations as described herein.

This part of ISO 6358 does not apply to any components whose flow coefficient is unstable during use (i.e.,

those that exhibit hysteretic behaviour or have an internal feedback phenomenon) and components that have

This part of ISO 6358 allows the determination of three sets of characteristic parameters: C, b and m, which

may be calculated from the test results. The sonic conductance, C, represents the choked flow rate. The

critical back-pressure ratio, b, represents the range of choked flow. The subsonic index, m, represents

The following referenced documents are indispensable for the application of this document. For dated

references, only the edition cited applies. For undated references, the latest edition of the referenced

ISO 1219-1, Fluid power systems and components — Graphic symbols and circuit diagrams — Part 1:

ISO 6358-2, Pneumatic fluid power — Determination of flow-rate characteristics of components using

ISO 6358-3, Pneumatic fluid power — Determination of flow-rate characteristics of components using

For the purpose of this International Standard, the terms and definitions in ISO 5598 and ISO 6358-2 apply.

NOTE Figure 1 illustrates basic circuit that does not incorporate all the safety devices necessary to protect against

damage in the event of component failure. It is important that those responsible for carrying out the test give due

DRAFT INTERNATIONAL STANDARD ISO/DIS 6358-4
ISO/TC 131/SC 5 Secretariat: AFNOR
Voting begins on: Voting terminates on:
2008-01-04 2008-06-04

INTERNATIONAL ORGANIZATION FOR STANDARDIZATION • МЕЖДУНАРОДНАЯ ОРГАНИЗАЦИЯ ПО СТАНДАРТИЗАЦИИ • ORGANISATION INTERNATIONALE DE NORMALISATION

Transmissions pneumatiques — Détermination des caractéristiques de débit des éléments traversés par un

To expedite distribution, this document is circulated as received from the committee secretariat.

ISO Central Secretariat work of editing and text composition will be undertaken at publication

Pour accélérer la distribution, le présent document est distribué tel qu'il est parvenu du

secrétariat du comité. Le travail de rédaction et de composition de texte sera effectué au

THIS DOCUMENT IS A DRAFT CIRCULATED FOR COMMENT AND APPROVAL. IT IS THEREFORE SUBJECT TO CHANGE AND MAY NOT BE

IN ADDITION TO THEIR EVALUATION AS BEING ACCEPTABLE FOR INDUSTRIAL, TECHNOLOGICAL, COMMERCIAL AND USER PURPOSES, DRAFT

INTERNATIONAL STANDARDS MAY ON OCCASION HAVE TO BE CONSIDERED IN THE LIGHT OF THEIR POTENTIAL TO BECOME STANDARDS TO

RECIPIENTS OF THIS DRAFT ARE INVITED TO SUBMIT, WITH THEIR COMMENTS, NOTIFICATION OF ANY RELEVANT PATENT RIGHTS OF WHICH

This PDF file may contain embedded typefaces. In accordance with Adobe's licensing policy, this file may be printed or viewed but shall

not be edited unless the typefaces which are embedded are licensed to and installed on the computer performing the editing. In

downloading this file, parties accept therein the responsibility of not infringing Adobe's licensing policy. The ISO Central Secretariat

Details of the software products used to create this PDF file can be found in the General Info relative to the file; the PDF-creation

parameters were optimized for printing. Every care has been taken to ensure that the file is suitable for use by ISO member bodies. In the

unlikely event that a problem relating to it is found, please inform the Central Secretariat at the address given below.

This ISO document is a Draft International Standard and is copyright-protected by ISO. Except as permitted

under the applicable laws of the user's country, neither this ISO draft nor any extract from it may be

reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, photocopying,

Requests for permission to reproduce should be addressed to either ISO at the address below or ISO's

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

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

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

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

3 Terms and definitions ...........................................................................................................................2

4 Symbols and units.................................................................................................................................2

5 Test installation .....................................................................................................................................2

5.1 Test circuit .............................................................................................................................................2

5.2 General requirements ...........................................................................................................................3

5.3 Requirements for the tank (item D) .....................................................................................................3

5.4 Special requirements ............................................................................................................................3

6 Test procedures.....................................................................................................................................3

6.1 Test conditions......................................................................................................................................3

6.1.1 Gas supply .............................................................................................................................................3

6.1.2 Checks....................................................................................................................................................3

6.1.3 Test measurements...............................................................................................................................4

6.2 Measuring procedures..........................................................................................................................4

6.3 Calculation of characteristics ..............................................................................................................6

6.3.1 Sonic conductance, C...........................................................................................................................6

6.3.2 Critical pressure ratio, b, and subsonic index, m ..............................................................................7

7 Presentation of test results ..................................................................................................................8

8 Identification statement ........................................................................................................................8

Annex A (normative) Errors and classes of measurement accuracy.........................................................9

A.1 Classes of measurement accuracy .....................................................................................................9

A.2 Errors......................................................................................................................................................9

A.3 Combination of errors...........................................................................................................................9

A.4 Expected variations...............................................................................................................................9

Annex B (informative) Equations for calculation of flow-rate characteristics ........................................10

Annex C (informative) Procedures for calculating flow-rate characteristics critical pressure

ratio, b, and subsonic index, m, by the least-square method using the Solver function in

Microsoft Excel....................................................................................................................................12

C.1 Function ...............................................................................................................................................12

C.2 Calculation of pressure, p ...........................................................................................................12

C.3 Calculation of critical pressure ratio, b, and subsonic index, m....................................................12

C.4 Start of Solver......................................................................................................................................12

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.

International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.

The main task of technical committees is to prepare International Standards. 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.

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.

ISO 6358-4 was prepared by Technical Committee ISO/TC 131, Fluid power systems, Subcommittee SC 5,

ISO 6358 consists of the following parts, under the general title Pneumatic fluid power — Determination of

⎯ Part 1: General rules for components with internal flow passages that are fixed

This part of ISO 6358 defines a charge test, or an alternative of the test method stated in ISO 6358-2 which

relates to a test method for flow-rate characteristics of pneumatic components. This alternative test method

tests a component by charging the atmospheric air to a tank which has already been evacuated. This method

allows obtaining the sonic conductance, critical pressure ratio and subsonic index of the component under

The charge test method specified in this part of ISO 6358 has the following advantages over the test method

This part of ISO 6358 specifies an alternative method for testing pneumatic fluid power components that use

compressible fluids, i.e. gases. It specifies requirements for the test installation, the test procedure and the

Accuracy of measurements is divided into two classes (A and B), which are explained in Annex A. Guidance

on the equation for calculation of characteristics is given in Annex B. Guidance on the procedures for

This part of ISO 6358 applies to the following components with inlet and outlet ports:

This part of ISO 6358 does not apply to any components whose flow coefficient is unstable during use (i.e.,

those that exhibit hysteretic behaviour or have an internal feedback phenomenon) and components that have

This part of ISO 6358 allows the determination of three sets of characteristic parameters: C, b and m, which

may be calculated from the test results. The sonic conductance, C, represents the choked flow rate. The

critical pressure ratio, b, represents the range of choked flow. The subsonic index, m, is the characteristic

index, which represents several conditions flow in a component such as a variable orifice.

The following referenced documents are indispensable for the application of this document. For dated

references, only the edition cited applies. For undated references, the latest edition of the referenced

ISO 1219-1, Fluid power systems and components — Graphic symbols and circuit diagrams — Part 1:

ISO 6358-2: , Pneumatic fluid power — Determination of flow-rate characteristics of components using

ISO 6358-3: , Pneumatic fluid power — Determination of flow-rate characteristics of components using

For the purpose of this International Standard, the terms and definitions given in ISO 5598 and part 2 of

4.1 The symbols and units shall be in accordance with parts 2 and part 3 of ISO 6358.

NOTE Figure 1 illustrates basic circuit that does not incorporate all the safety devices necessary to protect against

damage in the event of component failure. It is important that those responsible for carrying out the test give due

PROJET DE NORME INTERNATIONALE ISO/DIS 6358-4
ISO/TC 131/SC 5 Secrétariat: AFNOR
Début de vote: Vote clos le:
2008-01-04 2008-06-04

INTERNATIONAL ORGANIZATION FOR STANDARDIZATION • МЕЖДУНАРОДНАЯ ОРГАНИЗАЦИЯ ПО СТАНДАРТИЗАЦИИ • ORGANISATION INTERNATIONALE DE NORMALISATION

Pneumatic fluid power — Determination of flow-rate characteristics of components using compressible fluids —

Pour accélérer la distribution, le présent document est distribué tel qu'il est parvenu du

secrétariat du comité. Le travail de rédaction et de composition de texte sera effectué au

To expedite distribution, this document is circulated as received from the committee secretariat.

ISO Central Secretariat work of editing and text composition will be undertaken at publication

CE DOCUMENT EST UN PROJET DIFFUSÉ POUR OBSERVATIONS ET APPROBATION. IL EST DONC SUSCEPTIBLE DE MODIFICATION ET NE PEUT

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LES DESTINATAIRES DU PRÉSENT PROJET SONT INVITÉS À PRÉSENTER, AVEC LEURS OBSERVATIONS, NOTIFICATION DES DROITS DE

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Sauf autorisé par les lois en matière de droits d'auteur du pays utilisateur, aucune partie de ce projet ISO ne

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Les demandes d'autorisation de reproduction doivent être envoyées à l'ISO à l'adresse ci-après ou au comité

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

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

1 Domaine d'application ..........................................................................................................................1

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

3 Termes et définitions ............................................................................................................................2

4 Symboles et unités................................................................................................................................2

5 Installation d’essai ................................................................................................................................3

5.1 Circuit d’essai ........................................................................................................................................3

5.2 Prescriptions générales........................................................................................................................3

5.3 Prescriptions pour le réservoir (élément D) .......................................................................................4

5.4 Prescriptions spéciales ........................................................................................................................4

6 Modes opératoires d'essai ...................................................................................................................4

6.1 Conditions d’essai.................................................................................................................................4

6.1.1 Alimentation en gaz...............................................................................................................................4

6.1.2 Vérifications ...........................................................................................................................................4

6.1.3 Mesures de l’essai.................................................................................................................................4

6.2 Modes opératoires de mesure .............................................................................................................5

6.3 Calcul des caractéristiques..................................................................................................................6

6.3.1 Conductance sonique C .......................................................................................................................6

6.3.2 Rapport de pressions critique b et indice subsonique m.................................................................7

7 Présentation des résultats d’essai ......................................................................................................8

8 Phrase d’identification..........................................................................................................................8

Annexe A (normative) Erreurs et classes de précision de mesure ...............................................................9

A.1 Classes de précision de mesure..........................................................................................................9

A.2 Erreurs....................................................................................................................................................9

A.3 Addition des erreurs .............................................................................................................................9

A.4 Variations attendues .............................................................................................................................9

Annexe B (informative) Équations de calcul des caractéristiques de débit...............................................10

Annexe C (informative) Procédures de calcul des caractéristiques de débit telles que le rapport

de pressions critique b et l’indice subsonique m, par la méthode des moindres carrés en

utilisant la fonction Solveur de Microsoft Excel ..............................................................................12

C.1 Fonction...............................................................................................................................................12

C.2 Calcul de la pression p .................................................................................................................12

C.3 Calcul du rapport de pressions critique b et de l’indice subsonique m........................................12

C.4 Lancement de Solveur ........................................................................................................................12

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 Normes internationales sont rédigées conformément aux règles données dans les Directives ISO/CEI,

La tâche principale des comités techniques est d'élaborer les Normes internationales. 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

L'attention est appelée 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

L'ISO 6358-4 a été élaborée par le comité technique ISO/TC 131, Fluid power systems, sous-comité SC 5,

Cette deuxième édition annule et remplace la première édition (ISO 6358:1989), qui a fait l'objet d'une

L'ISO 6358 comprend les parties suivantes, présentées sous le titre général Transmissions pneumatiques —

Détermination des caractéristiques de débit des composants traversés par un fluide compressible :

La présente partie de l’ISO 6358 définit un essai de charge, ou une alternative à la méthode d’essai décrite

dans l’ISO 6358-2 qui traite d’une méthode d’essai pour les caractéristiques de débit des composants

pneumatiques. La présente méthode alternative teste un composant en chargeant l’air atmosphérique dans

un réservoir ayant déjà été vidé. Elle permet de déterminer, en fonction de la réponse en pression dans le

réservoir au cours de la charge, la conductance sonique, le rapport de pressions critique et l’indice

La méthode d’essai de charge donnée dans la présente partie de l’ISO 6358 possède, par rapport à celle

b) les composants avec de grandes capacités de débit peuvent être testés plus facilement ;

La présente partie de l'ISO 6358 donne une méthode alternative pour tester des composants de transmission

pneumatique utilisant des fluides compressibles - c'est à dire des gaz. Elle donne les prescriptions

La précision des mesures est divisée en deux classes (A et B), lesquelles sont expliquées en annexe A. Les

directives concernant les équations de calcul des caractéristiques sont données en annexe B. Les directives

concernant les procédures de calcul des caractéristiques de débit sont données en annexe C.

La présente partie de l'ISO 6358 s'applique aux composants suivants munis d’orifices d’entrée et de sortie :

⎯ les distributeurs de contrôle directionnel, tels que les électrodistributeurs ;

⎯ les composants de tuyauterie, tels que les connecteurs et les tubes flexibles ; et

La présente partie de l’ISO 6358 ne s’applique pas aux composants dont le coefficient de débit est instable

pendant leur fonctionnement (c'est-à-dire ceux présentant un comportement avec hystérésis ou un

phénomène de boucle de retour interne) ni aux composants ayant une pression d’ouverture, tels que les

Cette partie de l’ISO 6358 permet de déterminer trois jeux de paramètres caractéristiques : C, b et m, lesquels

peuvent être calculés à partir des résultats d’essais. La conductance sonique C, représente le débit sonique.

Le rapport de pressions critique b, représente la plage d'écoulement sonique. L’indice subsonique m, est

l’indice caractéristique qui représente plusieurs conditions de débit dans un composant comme un orifice

Les documents de référence suivants sont indispensables pour l'application du présent document. Pour les

références datées, seule l'édition citée s'applique. Pour les références non datées, la dernière édition du

ISO 1219-1, Transmissions hydrauliques et pneumatiques — Symboles graphiques et schémas de circuit —

ISO 6358-2 : , Transmissions pneumatiques - Détermination des caractéristiques de débit des composants

ISO 6358-3 : , Transmissions pneumatiques - Composants traversés par un fluide compressible -

Détermination des caractéristiques de débit - Partie 3 : Méthodes d’essai alternatives — Essai de décharge

Pour les besoins de la présente norme internationale, les termes et définitions donnés dans l’ISO 5598 et la

4.1 Les symboles et unités doivent être conformes aux parties 2 et 3 de l’ISO 6358.

4.2 Les symboles graphiques utilisés dans la Figure 1 sont conformes à l’ISO 1219-1.

NOTE La Figure 1 représente le circuit de base ne comportant pas tous les éléments de sécurité nécessaires à se

protéger des dégâts en cas de panne d’un composant. Il est important que les responsables des essais apportent