Hydraulic fluid power — Fatigue pressure testing of metal pressure-containing envelopes — Part 1: Test method

ISO 10771-1:2015 specifies a method of fatigue testing the pressure-containing envelopes of components used in hydraulic fluid power systems under sustained steady cyclic internal pressure loads. This part of ISO 10771 is only applicable to component pressure-containing envelopes that - are manufactured from metals, - are operated at temperatures that exclude creep and low-temperature embrittlement, - are only subjected to pressure-induced stresses, - are not subjected to loss of strength due to corrosion or other chemical action, and - might include gaskets, seals, and other non-metallic components; however, these are not considered part of the pressure-containing envelope being tested (see 5.7). ISO 10771-1:2015 does not apply to piping as defined in ISO 4413 (i.e. connectors, hose, tubing, pipe). See ISO 6803 and ISO 6605 for methods of fatigue testing of piping devices. ISO 10771-1:2015 establishes a general test method that is applicable for many hydraulic fluid power components, but additional requirements or more specific methods that can be required for particular components are contained in the annexes or other standards. Test pressure is to be determined by the user. See ISO/TR 10771‑2 for a possible rating method.

Transmissions hydrauliques — Essais de fatigue des enveloppes métalliques sous pression — Partie 1: Méthode d'essai

Fluidna tehnika - Hidravlika - Preskušanje utrujenosti kovinskih plaščev pod tlakom - 1. del: Preskusna metoda

Ta del standarda ISO 10771 določa metodo za preskušanje utrujenosti plaščev pod tlakom v sklopih komponent, ki se uporabljajo v hidravličnih pogonskih sistemih pod trajnimi nespremenljivimi cikličnimi notranjimi tlačnimi obremenitvami.
Ta del standarda ISO 10771 se uporablja samo za komponentne plašče pod tlakom, za katere velja naslednje:
– izdelani so iz kovin;
– delujejo pri temperaturah, ki izključujejo tečenje in krhkost pri nizki temperaturi;
– izpostavljeni so samo tlačnim obremenitvam;
– niso izpostavljeni izgubam trdnosti zaradi korozije ali druge kemične reakcije;
– lahko vključujejo tesnila, tesnilke in druge nekovinske komponente, vendar se ti ne obravnavajo kot del preskušanega plašča pod tlakom (glej 5.7).
Ta del standarda ISO 10771 se ne uporablja za ocevje, kot je opredeljeno v standardu ISO 4413 (tj. priključki, cevi, cevovodi, cevke). Za metode preskušanja utrujenosti cevovodnih naprav glej ISO 6803 in ISO 6605.
Ta del standarda ISO 10771 določa splošno preskusno metodo, ki se uporablja za številne hidravlične pogonske komponente, vendar dodatne zahteve ali podrobnejše metode, ki so lahko potrebne za določene komponente, so na voljo v dodatkih ali drugih standardih.
Preskusni tlak mora določiti uporabnik. Za možne metode ocenjevanja glej ISO/TR 10771-2.

General Information

Status
Published
Publication Date
20-Jul-2015
Current Stage
9093 - International Standard confirmed
Start Date
14-Jan-2021
Completion Date
14-Jan-2021

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INTERNATIONAL ISO
STANDARD 10771-1
Second edition
2015-08-01
Hydraulic fluid power — Fatigue
pressure testing of metal pressure-
containing envelopes —
Part 1:
Test method
Transmissions hydrauliques — Essais de fatigue des enveloppes
métalliques sous pression —
Partie 1: Méthode d’essai
Reference number
ISO 10771-1:2015(E)
ISO 2015
---------------------- Page: 1 ----------------------
ISO 10771-1:2015(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2015, Published in Switzerland

All rights reserved. Unless otherwise specified, 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
Ch. de Blandonnet 8 • CP 401
CH-1214 Vernier, Geneva, Switzerland
Tel. +41 22 749 01 11
Fax +41 22 749 09 47
copyright@iso.org
www.iso.org
ii © ISO 2015 – All rights reserved
---------------------- Page: 2 ----------------------
ISO 10771-1:2015(E)
Contents Page

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

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

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

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

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

4 Test conditions ....................................................................................................................................................................................................... 2

5 Test equipment and preparation......................................................................................................................................................... 2

6 Accuracy ........................................................................................................................................................................................................................ 3

7 Test procedure ........................................................................................................................................................................................................ 3

7.1 Cyclic pressure test .............................................................................................................................................................................. 3

7.1.1 Test pressure waveform ............................................................................................................................................ 3

7.1.2 Pressure test cycle .......................................................................................................................................................... 4

7.1.3 Number of test cycles ................................................................................................................................................... 4

7.1.4 Test frequency and time period, T ..................................................................................................................

1 4

7.2 General ........................................................................................................................................................................................................... 5

8 Failure criteria ........................................................................................................................................................................................................ 5

9 Test report ................................................................................................................................................................................................................... 6

10 Test declaration ..................................................................................................................................................................................................... 6

11 Identification statement (reference to this part of ISO 10771) ........................................................................... 6

Annex A (normative) Specific requirements for pumps and motors .................................................................................. 7

Annex B (normative) Specific requirements for hydraulic cylinders................................................................................. 8

Annex C (normative) Specific requirements for gas-loaded accumulators ..............................................................11

Annex D (normative) Specific requirements for valves .................................................................................................................13

Bibliography .............................................................................................................................................................................................................................14

© ISO 2015 – All rights reserved iii
---------------------- Page: 3 ----------------------
ISO 10771-1:2015(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 on the meaning of ISO specific terms and expressions related to conformity

assessment, as well as information about ISO’s adherence to the WTO principles in the Technical

Barriers to Trade (TBT) see the following URL: Foreword - Supplementary information.

The committee responsible for this document is ISO/TC 131, Fluid power systems, Subcommittee SC 8,

Product testing.

This second edition cancels and replaces the first edition (ISO 10771-1:2002), which has been

technically revised.

ISO 10771 consists of the following parts, under the general title Hydraulic fluid power — Fatigue

pressure testing of metal pressure-containing envelopes:
— Part 1: Test method
— Part 2: Rating methods [Technical Report]
Annex A to Annex D form a normative part of this part of ISO 10771.
iv © ISO 2015 – All rights reserved
---------------------- Page: 4 ----------------------
ISO 10771-1:2015(E)
Introduction

In hydraulic fluid power systems, power is transmitted and controlled under pressure within an enclosed

circuit. It is important for the manufacturer and user of hydraulic components to have information on

their global reliability because of the importance of the fatigue failure mode and the relationship this

has with the functional safety and service life of such components. This part of ISO 10771 provides a

method for fatigue testing the pressure-containing envelope provided by hydraulic components.

During operation, components in a system can be subjected to loads that arise from the following:

— internal pressure;
— external forces;
— inertia and gravitational effects;
— impact or shock;
— temperature changes or gradients.

The nature of these loads can vary from a single static application to continuously varying amplitudes,

repetitive loadings, and even shocks. It is important to know how a component can withstand these

loads, but this part of ISO 10771 addresses only the loading due to internal pressure.

There are many ways in which internal pressure loads are imposed upon a component. This part of

ISO 10771 considers a broad range of waveforms within prescribed time limits, temperatures, and

environmental conditions, and only upon metals. It is expected that these limitations could still provide

sufficient common ground for a method of fatigue pressure testing metal pressure-containing envelopes

in hydraulic fluid power components. This method, therefore, provides the system designer with certain

information to assist in a selection of components for an application. The system designer still has the

responsibility of considering the other loading characteristics described above and determining how

they could affect the component’s pressure-retaining capability.
© ISO 2015 – All rights reserved v
---------------------- Page: 5 ----------------------
INTERNATIONAL STANDARD ISO 10771-1:2015(E)
Hydraulic fluid power — Fatigue pressure testing of metal
pressure-containing envelopes —
Part 1:
Test method
1 Scope

This part of ISO 10771 specifies a method of fatigue testing the pressure-containing envelopes of

components used in hydraulic fluid power systems under sustained steady cyclic internal pressure loads.

This part of ISO 10771 is only applicable to component pressure-containing envelopes that

— are manufactured from metals,

— are operated at temperatures that exclude creep and low-temperature embrittlement,

— are only subjected to pressure-induced stresses,

— are not subjected to loss of strength due to corrosion or other chemical action, and

— might include gaskets, seals, and other non-metallic components; however, these are not considered

part of the pressure-containing envelope being tested (see 5.7).

This part of ISO 10771 does not apply to piping as defined in ISO 4413 (i.e. connectors, hose, tubing,

pipe). See ISO 6803 and ISO 6605 for methods of fatigue testing of piping devices.

This part of ISO 10771 establishes a general test method that is applicable for many hydraulic fluid

power components, but additional requirements or more specific methods that can be required for

particular components are contained in the annexes or other standards.

Test pressure is to be determined by the user. See ISO/TR 10771-2 for a possible rating method.

2 Normative references

The following documents, in whole or in part, are normatively referenced in this document and are

indispensable for its application. For dated references, only the edition cited applies. For undated

references, the latest edition of the referenced document (including any amendments) applies.

ISO 4413, Hydraulic fluid power — General rules and safety requirements for systems and their components

ISO 5598, Fluid power systems and components — Vocabulary

ISO 9110-1, Hydraulic fluid power — Measurement techniques — Part 1: General measurement principles

ISO 9110-2, Hydraulic fluid power — Measurement techniques — Part 2: Measurement of average steady-

state pressure in a closed conduit
3 Terms and definitions

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

© ISO 2015 – All rights reserved 1
---------------------- Page: 6 ----------------------
ISO 10771-1:2015(E)
3.1
upper cyclic test pressure
minimum value of the highest level of the specified test pressure cycle
3.2
lower cyclic test pressure
maximum value of the lowest level of the specified test pressure cycle
3.3
cyclic test pressure range

difference between the upper and lower cyclic test pressures during a fatigue test

3.4
pressure-containing envelope

elements of a component that contain the pressurized hydraulic fluid and the means to secure the

elements (bolts, welds, etc.)

Note 1 to entry: Gaskets and seals are not considered as part of the pressure-containing envelope.

Note 2 to entry: See annexes for component definitions.
4 Test conditions

4.1 Remove entrapped air from the test component and circuit before starting each test.

4.2 The temperature of the hydraulic fluid in the component shall be in the range of 15 °C to 80 °C. The

temperature of the component shall be a minimum of 15 °C.
5 Test equipment and preparation

5.1 The test equipment and circuit shall be able to generate and repeat the pressure cycle as

specified in 7.1.

5.2 Pressure transducer(s) shall be mounted directly into the test component, or as near as possible, so

as to record the internal conditions applied to the component. Any restrictions between the transducers

and the pressure-containing envelope being tested should be avoided.

5.3 Any non-corrosive hydraulic fluid that has a kinematic viscosity not greater than 60 mm /s at the

test temperature shall be used as the pressurizing medium.

5.4 Different pressures shall be applied to separate portions of the test components as dictated by

design specifications.

5.5 It shall be verified that the ratio of induced stress to pressure, under static loading conditions, is

also attained at the test cycling rate, especially when
— pressures have to penetrate between close-fitting parts,
— large components are tested, and
— hysteresis in joints can significantly affect stresses.

Strain gauges can be used to verify this ratio and, if used, should be located externally in an area of high

strain.
2 © ISO 2015 – All rights reserved
---------------------- Page: 7 ----------------------
ISO 10771-1:2015(E)

5.6 It is permissible to make modifications to the test samples to facilitate cyclic or burst tests, provided

that such modifications do not increase the pressure capabilities of the pressure-containing envelope.

5.7 It is permissible to replace gaskets and seals that fail during the test, as long as preloads in stressed

elements are the same after reassembly as they were before disassembly. It is possible that fastener

preloads can decrease during fatigue testing. Fastener preloads should be set
...

SLOVENSKI STANDARD
SIST ISO 10771-1:2016
01-maj-2016
1DGRPHãþD
SIST ISO 10771-1:2003
)OXLGQDWHKQLND+LGUDYOLND3UHVNXãDQMHXWUXMHQRVWLNRYLQVNLKSODãþHYSRG
WODNRPGHO3UHVNXVQDPHWRGD

Hydraulic fluid power - Fatigue pressure testing of metal pressure-containing envelopes -

Part 1: Test method
Transmissions hydrauliques - Essais de fatigue des enveloppes métalliques sous
pression - Partie 1: Méthode d'essai
Ta slovenski standard je istoveten z: ISO 10771-1:2015
ICS:
23.100.99 'UXJLVHVWDYQLGHOL Other fluid power system
KLGUDYOLþQLKVLVWHPRY components
SIST ISO 10771-1:2016 en

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

---------------------- Page: 1 ----------------------
SIST ISO 10771-1:2016
---------------------- Page: 2 ----------------------
SIST ISO 10771-1:2016
INTERNATIONAL ISO
STANDARD 10771-1
Second edition
2015-08-01
Hydraulic fluid power — Fatigue
pressure testing of metal pressure-
containing envelopes —
Part 1:
Test method
Transmissions hydrauliques — Essais de fatigue des enveloppes
métalliques sous pression —
Partie 1: Méthode d’essai
Reference number
ISO 10771-1:2015(E)
ISO 2015
---------------------- Page: 3 ----------------------
SIST ISO 10771-1:2016
ISO 10771-1:2015(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2015, Published in Switzerland

All rights reserved. Unless otherwise specified, 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
Ch. de Blandonnet 8 • CP 401
CH-1214 Vernier, Geneva, Switzerland
Tel. +41 22 749 01 11
Fax +41 22 749 09 47
copyright@iso.org
www.iso.org
ii © ISO 2015 – All rights reserved
---------------------- Page: 4 ----------------------
SIST ISO 10771-1:2016
ISO 10771-1:2015(E)
Contents Page

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

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

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

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

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

4 Test conditions ....................................................................................................................................................................................................... 2

5 Test equipment and preparation......................................................................................................................................................... 2

6 Accuracy ........................................................................................................................................................................................................................ 3

7 Test procedure ........................................................................................................................................................................................................ 3

7.1 Cyclic pressure test .............................................................................................................................................................................. 3

7.1.1 Test pressure waveform ............................................................................................................................................ 3

7.1.2 Pressure test cycle .......................................................................................................................................................... 4

7.1.3 Number of test cycles ................................................................................................................................................... 4

7.1.4 Test frequency and time period, T ..................................................................................................................

1 4

7.2 General ........................................................................................................................................................................................................... 5

8 Failure criteria ........................................................................................................................................................................................................ 5

9 Test report ................................................................................................................................................................................................................... 6

10 Test declaration ..................................................................................................................................................................................................... 6

11 Identification statement (reference to this part of ISO 10771) ........................................................................... 6

Annex A (normative) Specific requirements for pumps and motors .................................................................................. 7

Annex B (normative) Specific requirements for hydraulic cylinders................................................................................. 8

Annex C (normative) Specific requirements for gas-loaded accumulators ..............................................................11

Annex D (normative) Specific requirements for valves .................................................................................................................13

Bibliography .............................................................................................................................................................................................................................14

© ISO 2015 – All rights reserved iii
---------------------- Page: 5 ----------------------
SIST ISO 10771-1:2016
ISO 10771-1:2015(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 on the meaning of ISO specific terms and expressions related to conformity

assessment, as well as information about ISO’s adherence to the WTO principles in the Technical

Barriers to Trade (TBT) see the following URL: Foreword - Supplementary information.

The committee responsible for this document is ISO/TC 131, Fluid power systems, Subcommittee SC 8,

Product testing.

This second edition cancels and replaces the first edition (ISO 10771-1:2002), which has been

technically revised.

ISO 10771 consists of the following parts, under the general title Hydraulic fluid power — Fatigue

pressure testing of metal pressure-containing envelopes:
— Part 1: Test method
— Part 2: Rating methods [Technical Report]
Annex A to Annex D form a normative part of this part of ISO 10771.
iv © ISO 2015 – All rights reserved
---------------------- Page: 6 ----------------------
SIST ISO 10771-1:2016
ISO 10771-1:2015(E)
Introduction

In hydraulic fluid power systems, power is transmitted and controlled under pressure within an enclosed

circuit. It is important for the manufacturer and user of hydraulic components to have information on

their global reliability because of the importance of the fatigue failure mode and the relationship this

has with the functional safety and service life of such components. This part of ISO 10771 provides a

method for fatigue testing the pressure-containing envelope provided by hydraulic components.

During operation, components in a system can be subjected to loads that arise from the following:

— internal pressure;
— external forces;
— inertia and gravitational effects;
— impact or shock;
— temperature changes or gradients.

The nature of these loads can vary from a single static application to continuously varying amplitudes,

repetitive loadings, and even shocks. It is important to know how a component can withstand these

loads, but this part of ISO 10771 addresses only the loading due to internal pressure.

There are many ways in which internal pressure loads are imposed upon a component. This part of

ISO 10771 considers a broad range of waveforms within prescribed time limits, temperatures, and

environmental conditions, and only upon metals. It is expected that these limitations could still provide

sufficient common ground for a method of fatigue pressure testing metal pressure-containing envelopes

in hydraulic fluid power components. This method, therefore, provides the system designer with certain

information to assist in a selection of components for an application. The system designer still has the

responsibility of considering the other loading characteristics described above and determining how

they could affect the component’s pressure-retaining capability.
© ISO 2015 – All rights reserved v
---------------------- Page: 7 ----------------------
SIST ISO 10771-1:2016
---------------------- Page: 8 ----------------------
SIST ISO 10771-1:2016
INTERNATIONAL STANDARD ISO 10771-1:2015(E)
Hydraulic fluid power — Fatigue pressure testing of metal
pressure-containing envelopes —
Part 1:
Test method
1 Scope

This part of ISO 10771 specifies a method of fatigue testing the pressure-containing envelopes of

components used in hydraulic fluid power systems under sustained steady cyclic internal pressure loads.

This part of ISO 10771 is only applicable to component pressure-containing envelopes that

— are manufactured from metals,

— are operated at temperatures that exclude creep and low-temperature embrittlement,

— are only subjected to pressure-induced stresses,

— are not subjected to loss of strength due to corrosion or other chemical action, and

— might include gaskets, seals, and other non-metallic components; however, these are not considered

part of the pressure-containing envelope being tested (see 5.7).

This part of ISO 10771 does not apply to piping as defined in ISO 4413 (i.e. connectors, hose, tubing,

pipe). See ISO 6803 and ISO 6605 for methods of fatigue testing of piping devices.

This part of ISO 10771 establishes a general test method that is applicable for many hydraulic fluid

power components, but additional requirements or more specific methods that can be required for

particular components are contained in the annexes or other standards.

Test pressure is to be determined by the user. See ISO/TR 10771-2 for a possible rating method.

2 Normative references

The following documents, in whole or in part, are normatively referenced in this document and are

indispensable for its application. For dated references, only the edition cited applies. For undated

references, the latest edition of the referenced document (including any amendments) applies.

ISO 4413, Hydraulic fluid power — General rules and safety requirements for systems and their components

ISO 5598, Fluid power systems and components — Vocabulary

ISO 9110-1, Hydraulic fluid power — Measurement techniques — Part 1: General measurement principles

ISO 9110-2, Hydraulic fluid power — Measurement techniques — Part 2: Measurement of average steady-

state pressure in a closed conduit
3 Terms and definitions

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

© ISO 2015 – All rights reserved 1
---------------------- Page: 9 ----------------------
SIST ISO 10771-1:2016
ISO 10771-1:2015(E)
3.1
upper cyclic test pressure
minimum value of the highest level of the specified test pressure cycle
3.2
lower cyclic test pressure
maximum value of the lowest level of the specified test pressure cycle
3.3
cyclic test pressure range

difference between the upper and lower cyclic test pressures during a fatigue test

3.4
pressure-containing envelope

elements of a component that contain the pressurized hydraulic fluid and the means to secure the

elements (bolts, welds, etc.)

Note 1 to entry: Gaskets and seals are not considered as part of the pressure-containing envelope.

Note 2 to entry: See annexes for component definitions.
4 Test conditions

4.1 Remove entrapped air from the test component and circuit before starting each test.

4.2 The temperature of the hydraulic fluid in the component shall be in the range of 15 °C to 80 °C. The

temperature of the component shall be a minimum of 15 °C.
5 Test equipment and preparation

5.1 The test equipment and circuit shall be able to generate and repeat the pressure cycle as

specified in 7.1.

5.2 Pressure transducer(s) shall be mounted directly into the test component, or as near as possible, so

as to record the internal conditions applied to the component. Any restrictions between the transducers

and the pressure-containing envelope being tested should be avoided.

5.3 Any non-corrosive hydraulic fluid that has a kinematic viscosity not greater than 60 mm /s at the

test temperature shall be used as the pressurizing medium.

5.4 Different pressures shall be applied to separate portions of the test components as dictated by

design specifications.

5.5 It shall be verified that the ratio of induced stress to pressure, under static loading conditions, is

also attained at the test cycling rate, especially when
— pressures have to penetrate between close-fitting parts,
— large components are tested, and
— hysteresis in joints can significantly affect stresses.

Strain gauges can be used to verify this ratio and, if used, should be located externally in an area of high

strain.
2 © ISO 2015 – All rights reserved
---------------------- Page: 10 ----------------------
SIST ISO 10771-1:2016
ISO 10771-1:2015(E)
...

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