ISO/FDIS 18869

• Abstract:

  ISO 18869:2017 specifies methods for testing and evaluating the performance of quick-action couplings for use in hydraulic fluid power applications. This document does not apply to the testing of tube connections, stud ends for ports and flange connections, which are covered by ISO 19879. Test methods covered in this document are independent of each other and outline the method to follow for each test. See the respective connector standard for which tests to conduct and for performance requirements. It is not intended that all tests be carried out for every application; it is up to the user of this document to select the applicable tests. For qualification of the coupling, the minimum number of samples specified in this document is to be tested, unless otherwise specified in the relevant coupling standard or as agreed upon by the manufacturer and the user.

• Status: Not Published
• ICS: 23.100.01 - Fluid power systems in general
• Technical Committee: ISO/TC 131/SC 4 - Connectors and similar products and components
• Drafting Committee: ISO/TC 131/SC 4 - Connectors and similar products and components
• Current Stage: 5000 - FDIS registered for formal approval
• Start Date: 22-Jul-2026
• Completion Date: 04-May-2026

• Revises: ISO 18869:2017 - Hydraulic fluid power — Test methods for couplings actuated with or without tools
• Effective Date: 13-May-2023

Overview

ISO/FDIS 18869 specifies standardized laboratory test methods for evaluating the performance of quick-action couplings used in hydraulic fluid power systems. These couplings, actuated with or without tools, are essential components that allow for rapid connection and disconnection of fluid power lines. The standard details a broad range of independent test methods, empowering users to select only those relevant to their specific application or performance requirements. ISO/FDIS 18869 is an indispensable tool for manufacturers, designers, and users seeking to ensure the quality, safety, and reliability of hydraulic quick-action couplings in diverse industrial contexts.

Key Topics

• Quick-Action Couplings: Definitions, types (including tool-actuated and non-tool-actuated), and critical properties such as connect/disconnect force and torque.
• Test Selection and Sample Preparation: Guidance on how to select representative test assemblies, appropriate sample quantities, and reuse conditions based on destructive or non-destructive tests.
• Safety Protocols: Comprehensive recommendations addressing the hazards associated with hydraulic testing, including burst risks, high-pressure fluid jets, temperature extremes, and best practices for personnel protection.
• Performance Testing: Stepwise procedures and reporting requirements for key tests, such as:
  • Connect/disconnect force or torque measurement
  • Leakage tests at various pressures and configurations
  • Vacuum integrity tests
  • Air inclusion and fluid loss analysis
  • Pressure drop (Δp), impulse, burst, endurance, and corrosion resistance tests
• Test Apparatus and Accuracy: Specification for testing equipment, seals, measuring devices, and accuracy standards to ensure result consistency and repeatability.
• Reporting: Minimum data to be reported for qualification, including force/torque values, leakage rates, temperature and pressure data, and observations of any failures.

Applications

ISO/FDIS 18869 is critical for various players in the hydraulic fluid power sector:

• Manufacturers: To qualify new designs of hydraulic quick-action couplings and ensure ongoing product conformity to international benchmarks.
• System Integrators and OEMs: For quality assurance during equipment assembly and to verify the suitability of selected couplings for specific pressure, temperature, and endurance requirements.
• Third-Party Test Labs: To perform impartial, standardized testing for product certification, troubleshooting, or competitive benchmarking.
• End Users: To request or validate test reports demonstrating conformance of hydraulic connections to established safety and performance criteria, reducing risks of leakage, failure, or unsafe operation in automotive, aerospace, industrial, and mobile machinery applications.

By implementing ISO/FDIS 18869, organizations enhance system reliability and safety, lower maintenance costs, and ensure efficient operation with minimal fluid loss or air inclusion.

Related Standards

To gain a comprehensive understanding of hydraulic connector testing and product compatibility, reference the following related international standards:

• ISO 19879: Test and qualification of tube connections, stud ends, and flange connections in hydraulic fluid power applications.
• ISO 5598: Fluid power systems and components terminology.
• ISO 4411: Methods for determining differential pressure/flow rate characteristics in hydraulic valves.
• ISO 3601-3: Quality acceptance criteria for O-rings used in fluid power systems.
• ISO 9227: Salt spray tests for corrosion resistance.
• ISO 6802 & ISO 6803: Testing hydraulic hoses under impulse with and without flexing.

Employing ISO/FDIS 18869 in conjunction with these related standards helps support robust design, qualification, and ongoing validation of hydraulic systems, ensuring compliance to global best practices.

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Keywords: ISO 18869, hydraulic fluid power, quick-action couplings, test methods, leakage test, connect force, disconnect torque, fluid loss, air inclusion, international standard, performance evaluation, hydraulic system safety, component testing.

FINAL DRAFT
International
Standard
ISO/TC 131/SC 4
Hydraulic fluid power — Test
Secretariat: ANSI
methods for couplings actuated
Voting begins on:
with or without tools
2026-10-02
Transmissions hydrauliques — Méthodes d'essai pour les raccords
Voting terminates on:
actionnés avec ou sans outils
2026-11-27
RECIPIENTS OF THIS DRAFT ARE INVITED TO SUBMIT,
WITH THEIR COMMENTS, NOTIFICATION OF ANY
RELEVANT PATENT RIGHTS OF WHICH THEY ARE AWARE
AND TO PROVIDE SUPPOR TING DOCUMENTATION.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO­
LOGICAL, COMMERCIAL AND USER PURPOSES, DRAFT
INTERNATIONAL STANDARDS MAY ON OCCASION HAVE
TO BE CONSIDERED IN THE LIGHT OF THEIR POTENTIAL
TO BECOME STAN DARDS TO WHICH REFERENCE MAY BE
MADE IN NATIONAL REGULATIONS.
Reference number
FINAL DRAFT
International
Standard
ISO/TC 131/SC 4
Hydraulic fluid power — Test
Secretariat: ANSI
methods for couplings actuated
Voting begins on:
with or without tools
Transmissions hydrauliques — Méthodes d'essai pour les raccords
Voting terminates on:
actionnés avec ou sans outils
RECIPIENTS OF THIS DRAFT ARE INVITED TO SUBMIT,
WITH THEIR COMMENTS, NOTIFICATION OF ANY
RELEVANT PATENT RIGHTS OF WHICH THEY ARE AWARE
AND TO PROVIDE SUPPOR TING DOCUMENTATION.
© ISO 2026
IN ADDITION TO THEIR EVALUATION AS
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO­
LOGICAL, COMMERCIAL AND USER PURPOSES, DRAFT
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
INTERNATIONAL STANDARDS MAY ON OCCASION HAVE
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
TO BE CONSIDERED IN THE LIGHT OF THEIR POTENTIAL
or ISO’s member body in the country of the requester.
TO BECOME STAN DARDS TO WHICH REFERENCE MAY BE
MADE IN NATIONAL REGULATIONS.
ISO copyright office
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Published in Switzerland Reference number
ii
Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Selection of test assemblies . 3
5 General test conditions . 4
5.1 Safety considerations .4
5.2 Thread lubrication .5
5.3 Torque . .5
5.4 Test fluid and temperature .5
5.5 Test pressure .5
6 Test apparatus . 5
6.1 Test blocks (used in impulse, burst, sliding-impulse and overtightening tests) .5
6.2 Test seals .5
6.3 Measuring instruments .5
7 Connect force or torque test . 6
8 Disconnect force or torque test . 7
9 Leakage test . 7
9.1 Low pressure, coupled .7
9.2 Low–pressure, uncoupled (valved only) .9
9.3 Maximum working pressure, coupled .10
9.4 Maximum working pressure, uncoupled (valved only).10
10 Vacuum test . 10
10.1 General .10
10.2 Coupled test .10
10.3 Uncoupled test (valved only). 12
11 Air inclusion test .12
12 Fluid loss test . 14
13 Pressure drop, Δp, test .16
14 Static pressure test . 17
14.1 Coupled .17
14.2 Uncoupled (valved type only) .18
15 Specific temperature test .18
15.1 Maximum working temperature exposure .18
15.1.1 General .18
15.1.2 Coupled .18
15.1.3 Uncoupled (valved only) .18
15.2 Maximum working temperature service .19
15.2.1 Coupled .19
15.2.2 Uncoupled (valved only) .19
15.3 Minimum working temperature .19
15.3.1 Coupled .19
15.3.2 Uncoupled .19
16 Endurance test . 19
16.1 Couplings other than screw-to-connect types .19
16.2 Screw-to-connect couplings . 20
16.2.1 Principle . 20

iii
16.2.2 Procedure . 20
17 Overtightening test for screw-to-connect couplings only .21
17.1 Principle .21
17.2 Procedure .21
18 Burst test .23
18.1 Safety precautions . 23
18.2 Burst pressure, uncoupled (valved only) . 23
18.3 Burst pressure, coupled. 23
19 Pressure impulse test without flexing .23
19.1 Coupled . 23
19.2 Uncoupled (valved only) .24
20 Pressure impulse test with flexing (for coupling assemblies only) .24
20.1 Test apparatus.24
20.2 Positioning of the test item .24
20.3 Procedure . 25
21 Rotating impulse test .26
21.1 Procedure . 26
22 Surge flow test — Long duration .26
23 Surge flow test — Short duration .27
24 Corrosion resistance test .29
25 Test report and data presentation .29
26 Summary of information to be reported .29
27 Identification statement (reference to this document) .29
Annex A (normative) Test data form .30
Annex B (normative) Characteristic test with presence of internal pressure .34
Bibliography .37

iv
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 document 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).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent
rights in respect thereof. As of the date of publication of this document, ISO had not received notice of (a)
patent(s) which may be required to implement this document. However, implementers are cautioned that
this may not represent the latest information, which may be obtained from the patent database available at
www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.
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 4,
Connectors and similar products and components.
This second edition cancels and replaces the first edition (ISO 18869:2017), which has been technically
revised.
The main changes are as follows:
— in 4.3, Table 2, the columns (Destructive/Non-destructive testing) have been added together with the
indication when possible re-use the parts after testing;
— in 19.1, it has been specified to perform the impulse test coupled assembled with hoses.
A list of all parts in the ISO 18869 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.

v
Introduction
In hydraulic fluid power systems, power is transmitted and controlled through a liquid under pressure
within an enclosed circuit. Couplings are used to join or quickly separate fluid conductors. Quick-action
couplings, as defined in ISO 5598, can be connected and disconnected without the use of tools. Other types
of couplings require the use of tools for connection and disconnection.

vi
FINAL DRAFT International Standard ISO/FDIS 18869:2026(en)
Hydraulic fluid power — Test methods for couplings actuated
with or without tools
1 Scope
This document specifies methods for testing and evaluating the performance of quick-action couplings for
use in hydraulic fluid power applications. This document does not apply to the testing of tube connections,
stud ends for ports and flange connections, which are covered by ISO 19879.
Test methods covered in this document are independent of each other and outline the method to follow
for each test. See the respective connector standard for which tests to conduct and for performance
requirements. It is not intended that all tests be carried out for every application; it is up to the user of this
document to select the applicable tests.
For qualification of the coupling, the minimum number of samples specified in this document is to be tested,
unless otherwise specified in the relevant coupling standard or as agreed upon by the parties involved.
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 48-2, Rubber, vulcanized or thermoplastic — Determination of hardness — Part 2: Hardness between 10
IRHD and 100 IRHD
ISO 3448, Industrial liquid lubricants — ISO viscosity classification
ISO 3601-3, Fluid power systems — O-rings — Part 3: Quality acceptance criteria
ISO 4411, Hydraulic fluid power — Valves — Determination of differential pressure/flow rate characteristics
ISO 5598, Fluid power systems and components — Vocabulary
ISO 6508-1, Metallic materials — Rockwell hardness test — Part 1: Test method
ISO 6802, Rubber or plastics hoses and hose assemblies — Hydraulic impulse test with flexing
ISO 6803, Rubber or plastics hoses and hose assemblies — Hydraulic-pressure impulse test without flexing
ISO 9227, Corrosion tests in artificial atmospheres — Salt spray tests
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
quick-action coupling
connector that can be connected and disconnected multiple times and relatively quickly
EXAMPLE Within 1 s to 30 s either with or without the use of tools.
Note 1 to entry: This connector can contain one or two automatic shut-off valves.
3.2
screw-to-connect coupling
coupling that is designed to be connected and disconnected by more than one turn of one swivel element
relatively to the other
3.3
coupling half
uncoupled part of a quick-action coupling (3.1)
Note 1 to entry: The terms “socket half” and “plug half” can be used to describe the two parts of the coupling.
3.4
misalignment
maximum error in the space allowed between the axes of the two coupling halves, indicated in three
dimensions and angles of rotation
Note 1 to entry: See Figure 1.
Key
1 misalignment around C respect the X-axis
2 misalignment around C respect the Y-axis
3 misalignment around C respect the Z-axis
Figure 1 — Illustration of indication of misalignment
3.5
side load
load applied perpendicularly to the axes of the coupling
Note 1 to entry: See Figure B.1.

Note 2 to entry: The value of the side load is expressed in Newton (N).
3.6
maximum connect force
maximum force required to achieve a complete engagement of the connection
3.7
minimum disconnect force
minimum force required to achieve a complete disengagement of the connection
3.8
rated connect torque
torque required to achieve a complete engagement of the connection
3.9
rated disconnect torque
torque required to achieve a complete disengagement of the connection
4 Selection of test assemblies
4.1 Test assemblies (coupling assemblies to be tested) shall be selected to constitute a representative
sample of a production lot in all respects: design, material, surface treatment, process, etc. All managerial
controls necessary to maintain substantial similarity between test and production couplings shall be used.
4.2 For qualification testing, the number of test samples shall be taken from Table 1.
NOTE The coupling size is based on the nominal hose size, in accordance with ISO 4397.
Table 1 — Number of test samples
Coupling nominal size Number of samples
3,2 5
5 5
6,3 5
10 5
12,5 5
16 5
19 (20) 5
25 4
31,5 2
38 (40) 2
51 (50) 2
4.3 Conditions for re-use of test samples are indicated in Table 2. Parts used for non-destructive testing
can be used for further testing. Parts used for destructive testing shall not be tested further, used or
returned to stock.
Table 2 — Conditions for re-use of test samples
Type of test Test Clause Non-destructive Destructive
testing testing
Connect force or torque test 7 X
Disconnect force or torque test 8 X
Leakage test 9 X
Vacuum test 10 X
Air inclusion test 11 X
Fluid loss test 12 X
Pressure drop (Δp) test 13 X
a
Static pressure test 14 X
Specific temperature test 15 X
Endurance test 16 X
Overtightening test for screw-to- 17 X
connect couplings only
Burst test 18 X
Pressure impulse test without 19 X
flexing
Pressure impulse test with flexing 20 X
(for coupling assemblies only)
Rotating impulse test 21 X
Surge flow test – Long duration 22 X
Surge flow test –Short duration 23 X
Corrosion resistance test 24 X
a
In case that the specified static pressure is higher than the maximum working pressure the static pressure test shall be
consider as a destructive testing.
5 General test conditions
5.1 Safety considerations
5.1.1 The following recommendations are not all inclusive and other pertinent regulations and
considerations can apply.
5.1.2 Some of the tests described in this document are considered hazardous. It is therefore essential that,
in conducting these tests, all appropriate safety precautions be strictly applied. In particular, attention is
drawn to the following situations:
a) bursting of the coupling or hose;
b) fine jets, which can penetrate the skin;
c) energy release caused by expanding gases;
d) handling of objects at high and low temperatures;
e) movement of actuators and metallic parts when attachments and the endurance test machine are used.
5.1.3 Tests shall be set up and performed by properly trained personnel.
5.1.4 To reduce the hazard of fluid injection, test assemblies shall be protected with adequate safeguards.

5.1.5 To reduce the hazard of energy release, air shall be bled from test assemblies before applying
pressure.
5.1.6 To reduce the hazard of burns, test assemblies shall be handled with the appropriate tools.
5.1.7 To reduce the risk of injury to personnel, test equipment and test assemblies shall be protected with
adequate safeguards, and moving automatic mechanisms shall not be operated manually.
5.1.8 Appropriate personal protective equipment shall be used at all times during testing.
5.2 Thread lubrication
For all tests on connectors made of carbon steel and for testing only, threads and contact surfaces shall be
lubricated prior to application of torque with hydraulic fluid with a viscosity of ISO VG 32 in accordance with
ISO 3448. For connectors made of materials other than carbon steel, the manufacturer’s recommendation
for thread lubrication shall be followed.
5.3 Torque
For all tests, connectors used in the test bench shall be assembled using the torque of the respective
standard.
5.4 Test fluid and temperature
The test fluid shall have a maximum viscosity of ISO VG 32, in accordance with ISO 3448, unless otherwise
specified. If not specified, tests shall be carried out at an ambient temperature from 20 °C to 35 °C.
5.5 Test pressure
The test pressure shall be as specified in the respective connector standard.
6 Test apparatus
6.1 Test blocks (used in impulse, burst, sliding-impulse and overtightening tests)
Test blocks shall be unpainted and have hardness between 35 HRC and 45 HRC in accordance with
ISO 6508-1. If a test block has multiple ports, the distance between the centrelines of test ports shall be a
minimum of 1,5 times the port diameter. The distance between the port centreline and the edge of the test
block shall be a minimum of 1 time the port diameter.
6.2 Test seals
For all tests except for the overtightening test and unless otherwise specified, seals used in the ports shall
be made from nitrile (NBR) rubber with a hardness of 90 IRHD ± 5 IRHD when measured in accordance
with ISO 48-2. Seals shall conform to their respective dimensional requirements, and O-rings shall meet or
exceed the quality requirements for grade N (general purpose) of ISO 3601-3.
6.3 Measuring instruments
Measuring instruments used shall provide the accuracy given in Table 3.

Table 3 — Required accuracy of instruments used to measure data
Parameter Unit Data accuracy
(percentage of maximum measured value)
Flow rate l/min ±3 %
Force N ±3 %
Pressure and MPa ±3 %
pressure drop
Torque N·m ±3 %
Volume ml ±1 %
(leakage)
Temperature °C ±3 °C
7 Connect force or torque test
7.1 The instructions given in Annex B on how to conduct this test shall be followed when internal pressure
is present in the coupling
7.2 The coupling interfaces of the test assembly shall be lubricated with the test fluid. Insert the test
assembly in a test fixture. Maintain the internal test pressure as specified in the respective connector
standard or as agreed by the parties involved. Conduct the test using the parameters and procedures given
in Table 4.
Table 4 — Parameters and procedures for connect force and disconnect force test
Test parameter Value of parameter and procedure
Test medium As specified in Clause 5
Test pressure and As specified in Clause 5 or as specified in the respective
temperature connector standard or as agreed by the parties involved
Test ambient As specified in the respective connector standard or as
conditions agreed by the parties involved
Pass/fail criteria Any mechanical damages compromising the capability to
connect and disconnect shall be considered a test failure.
Acceptable fluid loss and air inclusion should be as speci-
fied in the respective connector standard or as agreed by
the parties involved. Any deviation shall be considered a
test failure.
7.3 Apply a linear force or torque to the coupling half until complete connection occurs. During this
operation, the locking mechanism may be operated manually, if necessary, to permit normal coupling of the
halves.
7.4 Measure the connect force or connect torque or both, as appropriate.
7.5 Repeat the test for a total of five times on the same test assembly. Average the results of the five tests to
determine the connect force or torque. Report the average in the test report. This value is the rated connect
force or rated connect torque.
7.6 Report any failures identified in Table 4 (e.g. damage, malfunction, leakage) in the test report.

8 Disconnect force or torque test
8.1 The instructions given in Annex B on how to conduct this test shall be followed when internal pressure
is present in the coupling
8.2 Lubricate the coupling interfaces of the test assembly with the test fluid. Insert the test assembly in
a test fixture. Maintain the internal test pressure either as specified in the respective connector standard
or as agreed by the parties involved or in accordance with the prevailing flow conditions. Conduct the test
using the parameters and procedures given in Table 4.
8.3 Apply linear force or torque to the retaining mechanism of the coupling until disconnection occurs.
8.4 Measure the disconnect force or torque, as appropriate.
8.5 Repeat the test for a total of five disconnections on the same test assembly. Average the test results of
the five tests to determine the disconnect force or torque. Report the average in the test report. This value is
the rated disconnect force or the rated disconnect torque.
8.6 Report any failures identified in Table 4 (e.g. damage, malfunction, leakage) in the test report.
9 Leakage test
9.1 Low pressure, coupled
9.1.1 Insert the test assembly in a test apparatus, as shown in Figure 2. Fill the test apparatus with test
fluid (5.4) to a fluid column height of 750 mm. Apply a 50 N load perpendicular to the coupling centreline
at a distance of 10D from the centreline of the main interface seal, where D is the nominal coupling size, in
millimetres.
Key
1 inside diameter, maximum 13 mm
2 column with top portion graduated for measurement
3 plug coupling half
4 steel rod connected to the plug coupling half not held in the fixture
5 50 N load perpendicular to centreline of the coupling
6 centreline of the main interface seal (see detail)
7 fixture to hold the socket coupling half
8 socket coupling half
9 head fluid column
A section detail: first sealing element
D nominal size of the coupling
Figure 2 — Test apparatus for the low pressure leakage test, coupled
9.1.2 Measure the drop in column height over a minimum test period of 30 min. Calculate the leakage rate
in millilitres per hour.
9.1.3 Report the leakage rate in the test report.

9.2 Low–pressure, uncoupled (valved only)
9.2.1 Insert each coupling half into the test apparatus, as shown in Figure 3. Fill the test apparatus with
test fluid (5.4) to a fluid column height of 750 mm.
Key
1 inside diameter, maximum 13 mm
2 column with top portion graduated for measurement
3 coupling half (plug or socket) under test
4 top of column open to atmosphere
5 head fluid column
Figure 3 — Test apparatus for the low pressure leakage test, uncoupled
9.2.2 Measure the drop in column height over a test period of 30 min. Calculate the leakage rate in
millilitres per hour.
9.2.3 Report the leakage rate in the test report.
9.3 Maximum working pressure, coupled
9.3.1 Purge internal air from the circuit. Pressurize the coupling assembly with the test fluid at the rated
pressure or maximum pressure specified in the respective connector standard or as agreed by the parties
involved, and maintain this pressure level for a test period of 30 min.
9.3.2 During the test period, observe any leakage and collect and measure it in a graduated measuring
flask. Calculate the leakage rate in millilitres per hour.
9.3.3 Report the leakage rate in the test report.
9.4 Maximum working pressure, uncoupled (valved only)
9.4.1 Purge internal air from the circuit. Pressurize the coupling half with the test fluid at the rated
pressure or maximum pressure specified in the respective connector standard or as agreed by the parties
involved, and maintain this pressure level for a test period of 30 min.
9.4.2 During the test period, observe any leakage from each coupling half and collect and measure it in a
graduated measuring flask. Calculate the leakage rate in millilitres per hour.
9.4.3 Report the leakage rate in the test report.
10 Vacuum test
10.1 General
This procedure is recommended only for vacuum tests for which measurement of a leakage rate is not
required.
10.2 Coupled test
10.2.1 Insert the coupling assembly in a test apparatus as shown in Figure 4.

Key
1 fixture to hold socket coupling half
2 coupling or coupling half under test
3 plug coupling half
4 steel rod connected to plug coupling half not held in the fixture
5 50 N load perpendicular to the centreline of the coupling under test
6 centreline of the main interface seal
7 socket coupling half
8 manometer
9 vacuum pump
10 valve
A section detail: first sealing element
D the nominal size of the coupling
L maximum 15D
NOTE Side load is applied only during the coupled test.
Figure 4 — Apparatus for vacuum test
10.2.2 Apply the side load to the coupling assembly, as shown in Figure 4.
10.2.3 Start the vacuum pump and create a vacuum to the value specified in the respective connector
standard or as agreed by the parties involved.
10.2.4 Close the valve and allow 10 min for stabilization.

10.2.5 Observe the vacuum gauge for any loss of vacuum.
10.2.6 Report the gauge reading in the test report.
10.3 Uncoupled test (valved only)
10.3.1 Insert each coupling half in a test apparatus as shown in Figure 4.
10.3.2 Start the vacuum pump and create a vacuum to the value specified in the respective connector
standard or as agreed by the parties involved.
10.3.3 Close the valve and allow 10 min for stabilization.
10.3.4 Observe the vacuum gauge for any loss of vacuum.
10.3.5 Report the gauge reading in the test report.
11 Air inclusion test
11.1 Insert the coupling assembly in a test apparatus as shown in Figure 5. Record the fluid level of the
closed graduated cylinder, with the coupling connected and the fluid levels coincident.

Key
1 open-top vessel with fluid
2 mating coupling half
3 fixed coupling half
4 closed graduated vessel with test fluid
a
Reading shall be taken when fluid levels are coincident.
b
If an air bubble appears in this vessel, the test shall be rerun, because the air has come from air trapped in the
coupling.
c
A lanyard may be used to prevent accidental dropping of the plug half below the 250 mm minimum
requirement.
d
Difference in the volume of entrapped air represents the total air inclusion.
Figure 5 — Apparatus for the air inclusion test
11.2 Uncouple and couple the coupling assembly and allow lost fluid to drain after uncoupling. After
each uncoupling/coupling cycle, tap the coupling assembly to clear all air bubbles from the interior of the
assembly.
11.3 Repeat the procedures specified in 11.2 until the fluid displaced by air in the graduated cylinder
exceeds 10 minor divisions on the graduated scale. With the coupling coupled, adjust the open-top vessel
vertically so that the fluid levels are coincident. Record the fluid level of the graduated cylinder.

11.4 Subtract the fluid level value recorded in 11.3 from the value recorded in 11.1 and divide the difference
by the number of coupling/uncoupling cycles.
11.5 Report the air inclusion in millilitres per coupling/uncoupling cycle in the test report.
12 Fluid loss test
12.1 Insert the coupling assembly in a test apparatus as shown in Figure 6. Maintain a fluid pressure of
0,1 MPa (1 bar) in the graduated vessel with test fluid. If the viscosity of the test fluid prevents prompt
clearing of bubbles, use a fluid with a lower viscosity and record the fluid type used. Record the fluid level of
the graduated vessel.
Key
1 graduated vessel with test fluid
2 Y connector
3 rigid tubing
4 polytetrafluorethylene (PTFE) tubing
5 mating coupling half
6 fixed coupling half
a
Fluid pressure inlet.
Figure 6 — Apparatus for the fluid loss test
12.2 Couple and uncouple the assembly. After each uncoupling, allow the fluid loss to drain from the
assembly. After each coupling, tap the assembly to clear all air bubbles from the interior of the coupling.
12.3 Repeat the procedures in 12.2 until the fluid level of the graduated vessel has dropped a minimum of
10 minor divisions on the scale. Record the fluid level of the graduated vessel.
12.4 Subtract the fluid level value recorded in 12.3 from the value recorded in 12.1 and divide the difference
by the number of coupling/uncoupling cycles.

12.5 Report the value calculated in 12.4 as the fluid loss in millilitres per coupling/uncoupling cycle in the
test report, S .
nc
13 Pressure drop, Δp, test
13.1 Insert the test coupling in a test apparatus as shown in Figure 7; the pressure tap shall be in accordance
with ISO 4411, classes of measurement accuracy B and C. Select at least six flow rates from 25 % to 150 %
of the rated flow, including 100 % of rated flow. If the rated flow is not specified in the respective connector
standard, use the values given in Table 5.
Key
1 coupling under test
2 pressure tap
3 differential pressure measuring device
4 controlled fluid supply
NOTE Dimensions L to L are minimum lengths:
1 5
L 10 times the inside diameter of the coupling tube or pipe;
L 5 times the inside diameter of the coupling tube or pipe;
L length of the coupling plus end fittings;
L 10 times the inside diameter of the coupling tube or pipe;
L 5 times the inside diameter of the coupling tube or pipe; as alternative the flow meter can be positioned at the
beginning of L1.
Figure 7 — Apparatus for the pressure drop test
Table 5 — Typical rated flows
Coupling size Rated flow
(nominal hose size) Q
R
mm l/min
3,2 3
5 6
6,3 12
10 23
12,5 45
TTaabblle 5 e 5 ((ccoonnttiinnueuedd))
Coupling size Rated flow
(nominal hose size) Q
R
mm l/min
16 74
19 (20) 100 (106)
25 189
31,5 288
38 (40) 342 (379)
51 (50) 788(757)
13.2 Determine and record the pressure drop of the test coupling in plug-half-to-socket-half and socket
-half-to-plug-half directions, at the flow rates selected in 13.1.
13.3 Remove the test coupling from the test apparatus and connect the tubes or pipes using an appropriate
adaptor with the same or shorter length than the tested coupling and the same inside diameter as the tubes
or pipes to ensure the continuity of the internal geometry. Determine and record the pressure drop at the
same flow rates selected in 13.1.
2 2
13.4 Maintain the viscosity of the test fluid at 28,8 mm /s to 35,2 mm /s throughout the test. Record the
...

ISO /TC 131/SC 4
Secretariat: ANSI
Date: 2026-07-25xx
Hydraulic fluid power — Test methods for couplings actuated with or
without tools
Transmissions hydrauliques — Méthodes d'essai pour les raccords actionnés avec ou sans outils
FDIS stage
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: + 41 22 749 01 11
EmailE-mail: [e-mail]
Website: www.iso.org
Published in Switzerland
ii
Contents
Foreword . v
Introduction . vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Selection of test assemblies. 3
5 General test conditions . 4
5.1 Safety considerations . 4
5.2 Thread lubrication . 5
5.3 Torque . 5
5.4 Test fluid and temperature . 5
5.5 Test pressure . 5
6 Test apparatus . 5
6.1 Test blocks (used in impulse, burst, sliding-impulse and overtightening tests) . 5
6.2 Test seals . 5
6.3 Measuring instruments . 6
7 Connect force or torque test . 6
8 Disconnect force or torque test . 7
9 Leakage test . 7
9.1 Low pressure, coupled . 7
9.2 Low–pressure, uncoupled (valved only) . 9
9.3 Maximum working pressure, coupled . 10
9.4 Maximum working pressure, uncoupled (valved only) . 10
10 Vacuum test . 10
10.1 General . 10
10.2 Coupled test . 10
10.3 Uncoupled test (valved only) . 12
11 Air inclusion test . 12
12 Fluid loss test . 14
13 Pressure drop, Δp, test . 15
14 Static pressure test . 17
14.1 Coupled . 17
14.2 Uncoupled (valved type only) . 17
15 Specific temperature test . 17
15.1 Maximum working temperature exposure . 17
15.2 Maximum working temperature service . 18
15.3 Minimum working temperature. 18
16 Endurance test . 19
16.1 Couplings other than screw-to-connect types . 19
16.2 Screw-to-connect couplings . 19
17 Overtightening test for screw-to-connect couplings only . 20
17.1 Principle . 20
17.2 Procedure . 20
iii
18 Burst test . 22
18.1 Safety precautions . 22
18.2 Burst pressure, uncoupled (valved only) . 22
18.3 Burst pressure, coupled . 22
19 Pressure impulse test without flexing. 22
19.1 Coupled . 22
19.2 Uncoupled (valved only) . 23
20 Pressure impulse test with flexing (for coupling assemblies only) . 23
20.1 Test apparatus . 23
20.2 Positioning of the test item. 23
20.3 Procedure . 24
21 Rotating impulse test . 25
21.1 Procedure . 25
22 Surge flow test — Long duration . 25
23 Surge flow test — Short duration . 26
24 Corrosion resistance test . 28
25 Test report and data presentation . 28
26 Summary of information to be reported . 28
27 Identification statement (reference to this document) . 28
Annex A (normative) Test data form . 29
Annex B (normative) Characteristic test with presence of internal pressure . 34
Bibliography . 37

iv
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 documentsdocument 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 drawnISO draws attention to the possibility that some of the elementsimplementation of this
document may beinvolve the subjectuse of (a) patent(s). ISO takes no position concerning the evidence,
validity or applicability of any claimed patent rights in respect thereof. As of the date of publication of this
document, ISO had not received notice of (a) patent(s) which may be required to implement this document.
However, implementers are cautioned that this may not represent the latest information, which may be
obtained from the patent database available at www.iso.org/patents. 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 ).
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 4,
Connectors and similar products and components.
This second edition cancels and replaces the first edition (ISO 18869:2017), which has been technically
revised.
The main changes are as follows:
— in 4.3, Table 2— In Clause 4.3 Table 2, the columns (Destructive/Non-destructive testing) it
hashave been added together with the indication when possible re-use the parts after testing.;
— in 19.1— In Clause 19.1, it has been specified to perform the impulse test coupled assembled with hoses.
A list of all parts in the ISO 18869 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
v
Introduction
In hydraulic fluid power systems, power is transmitted and controlled through a liquid under pressure within
an enclosed circuit. Couplings are used to join or quickly separate fluid conductors. Quick-action couplings, as
defined in ISO 5598, can be connected and disconnected without the use of tools. Other types of couplings
require the use of tools for connection and disconnection.
vi
Hydraulic fluid power — Test methods for couplings actuated with or
without tools
1 Scope
This document specifies methods for testing and evaluating the performance of quick-action couplings for use
in hydraulic fluid power applications. This document does not apply to the testing of tube connections, stud
ends for ports and flange connections, which are covered by ISO 19879.
Test methods covered in this document are independent of each other and outline the method to follow for
each test. See the respective connector standard for which tests to conduct and for performance requirements.
It is not intended that all tests be carried out for every application; it is up to the user of this document to select
the applicable tests.
For qualification of the coupling, the minimum number of samples specified in this document is to be tested,
unless otherwise specified in the relevant coupling standard or as agreed upon by the parties involved.
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 48--2, Rubber, vulcanized or thermoplastic — Determination of hardness — Part 2: Hardness between 10
IRHD and 100 IRHD
ISO 3448, Industrial liquid lubricants — ISO viscosity classification
ISO 3601--3, Fluid power systems — O-rings — Part 3: Quality acceptance criteria
ISO 4411, Hydraulic fluid power — Valves — Determination of differential pressure/flow rate characteristics
ISO 5598, Fluid power systems and components — Vocabulary
ISO 6508--1, Metallic materials — Rockwell hardness test — Part 1: Test method
ISO 6802, Rubber or plastics hoses and hose assemblies — Hydraulic impulse test with flexing
ISO 6803, Rubber or plastics hoses and hose assemblies — Hydraulic-pressure impulse test without flexing
ISO 9227, Corrosion tests in artificial atmospheres — Salt spray tests
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 3.1
quick-action coupling
connector that can be connected and disconnected multiple times and relatively quickly
ExampleEXAMPLE Within 1 s to 30 s either with or without the use of tools.
Note 1 to entry: This connector can contain one or two automatic shut-off valves.
3.2 3.2
screw-to-connect coupling
coupling that is designed to be connected and disconnected by more than one turn of one swivel element
relatively to the other
3.3 3.3
coupling half
uncoupled part of a quick-action coupling (3.1(3.1))
Note 1 to entry: The terms “socket half” and “plug half” can be used to describe the two parts of the
coupling.
3.4 3.4
misalignment
maximum error in the space allowed between the axes of the two coupling halves, indicated in three
dimensions and angles of rotation
Note 1 to entry: See Figure 1Figure 1.
18869_ed2fig1.EPS
Key
1 misalignment around C respect the X-axis
2 misalignment around C respect the Y-axis
3 misalignment around C respect the Z-axis
Figure 1 — Illustration of indication of misalignment
3.5 3.5
side load
load applied perpendicularperpendicularly to the axes of the coupling
Note 1 to entry: See Figure B.1Figure B.1.
Note 2 to entry: The value of the side load is expressed in Newton (N).
3.6 3.6
maximum connect force
maximum force required to achieve a complete engagement of the connection
3.7 3.7
minimum disconnect force
minimum force required to achieve a complete disengagement of the connection
3.8 3.8
rated connect torque
torque required to achieve a complete engagement of the connection
3.9 3.9
rated disconnect torque
torque required to achieve a complete disengagement of the connection
4 Selection of test assemblies
4.1 4.1 Test assemblies (coupling assemblies to be tested) shall be selected to constitute a
representative sample of a production lot in all respects: design, material, surface treatment, process, etc. All
managerial controls necessary to maintain substantial similarity between test and production couplings shall
be used.
4.2 4.2 For qualification testing, the number of test samples shall be taken from Table 1Table 1.
NOTE The coupling size is based on the nominal hose size, in accordance with ISO 4397.
Table 1 — Number of test samples
Coupling nominal Number of samples
size
3,2 5
5 5
6,3 5
10 5
12,5 5
16 5
19 (20) 5
25 4
31,5 2
38 (40) 2
51 (50) 2
4.3 4.3 Conditions for re-use of test samples are indicated in Table 2Table 2. Parts used for non-
destructive testing can be used for further testing. Parts used for destructive testing shall not be tested further,
used or returned to stock.
Table 2 — Conditions for re-use of test samples
Type of Testtest Test Clause Non-Destructive Destructive
Testingdestructive Testingtesting
testing
Connect force or torque test 77 X
Disconnect force or torque test 88 X
Leakage test 99 X
Vacuum test 1010 X
Air inclusion test 1111 X
Fluid loss test 1212 X
Pressure drop (Δp) test 1313 X
a 14
Static pressure test 14 X
Specific temperature test 1515 X
Endurance test 1616  X
Overtightening test for screw-to- 1717  X
connect couplings only
Burst test 1818  X
Pressure impulse test without 1919  X
flexing
Pressure impulse test with flexing 2020  X
(for coupling assemblies only)
Rotating impulse test 2121  X
Surge flow test – Long duration 2222  X
Surge flow test –Short duration 2323  X
Corrosion resistance test 2424  X
a In case that the specified static pressure is higher than the maximum working pressure the static pressure test shall be consider
as a destructive testing.
5 General test conditions
5.1 Safety considerations
5.1.1 5.1.1 The following recommendations are not all inclusive and other pertinent regulations and
considerations can apply.
5.1.2 5.1.2 Some of the tests described in this document are considered hazardous. It is therefore essential
that, in conducting these tests, all appropriate safety precautions be strictly applied. In particular, attention is
drawn to the following situations:
a) a) bursting of the coupling or hose;
b) b) fine jets, which can penetrate the skin;
c) c) energy release caused by expanding gases;
d) d) handling of objects at high and low temperatures;
e) e) movement of actuators and metallic parts when attachments and the endurance test machine
are used.
5.1.3 5.1.3 Tests shall be set up and performed by properly trained personnel.
5.1.4 5.1.4 To reduce the hazard of fluid injection, test assemblies shall be protected with adequate
safeguards.
5.1.5 5.1.5 To reduce the hazard of energy release, air shall be bled from test assemblies before applying
pressure.
5.1.6 5.1.6 To reduce the hazard of burns, test assemblies shall be handled with the appropriate tools.
5.1.7 5.1.7 To reduce the risk of injury to personnel, test equipment and test assemblies shall be protected
with adequate safeguards, and moving automatic mechanisms shall not be operated manually.
5.1.8 5.1.8 Appropriate personal protective equipment shall be used at all times during testing.
5.2 Thread lubrication
For all tests on connectors made of carbon steel and for testing only, threads and contact surfaces shall be
lubricated prior to application of torque with hydraulic fluid with a viscosity of ISO VG 32 in accordance with
ISO 3448. For connectors made of materials other than carbon steel, the manufacturer’s recommendation for
thread lubrication shall be followed.
5.3 Torque
For all tests, connectors used in the test bench shall be assembled using the torque of the respective standard.
5.4 Test fluid and temperature
The test fluid shall have a maximum viscosity of ISO VG 32, in accordance with ISO 3448, unless otherwise
specified. If not specified, tests shall be carried out at an ambient temperature from 20 °C to 35 °C.
5.5 Test pressure
The test pressure shall be as specified in the respective connector standard.
6 Test apparatus
6.1 Test blocks (used in impulse, burst, sliding-impulse and overtightening tests)
Test blocks shall be unpainted and have hardness between 35 HRC and 45 HRC in accordance with ISO 6508--
1. If a test block has multiple ports, the distance between the centrelines of test ports shall be a minimum of
1,5 times the port diameter. The distance between the port centreline and the edge of the test block shall be a
minimum of 1 time the port diameter.
6.2 Test seals
For all tests except for the overtightening test and unless otherwise specified, seals used in the ports shall be
made from nitrile (NBR) rubber with a hardness of 90 IRHD ± 5 IRHD when measured in accordance with ISO
48-2. Seals shall conform to their respective dimensional requirements, and O-rings shall meet or exceed the
quality requirements for grade N (general purpose) of ISO 3601--3.
6.3 Measuring instruments
Measuring instruments used shall provide the accuracy given in Table 3Table 3.
Table 3 — Required accuracy of instruments used to measure data
Parameter Unit Data accuracy
(percentage of maximum measured
value)
Flow rate l/min ±3 %
Force N ±3 %
Pressure and MPa ±3 %
pressure drop
Torque N·m ±3 %
Volume ml ±1 %
(leakage)
Temperature °C ±3 °C
7 Connect force or torque test
7.1 7.1 The instructions given in Annex BAnnex B on how to conduct this test shall be followed when
internal pressure is present in the coupling
7.2 7.2 The coupling interfaces of the test assembly shall be lubricated with the test fluid. Insert the
test assembly in a test fixture. Maintain the internal test pressure as specified in the respective connector
standard or as agreed by the parties involved. Conduct the test using the parameters and procedures given in
Table 4Table 4.
Table 4 — Parameters and procedures for connect force and disconnect force test
Test parameter Value of parameter and procedure
Test medium As specified in Clause 5Clause 5
Test pressure and As specified in Clause 5Clause 5 or as specified in the
temperature respective connector standard or as agreed by the parties
involved
Test ambient As specified in the respective connector standard or as
conditions agreed by the parties involved
Pass/fail criteria Any mechanical damages compromising the capability to
connect and disconnect shall be considered a test failure.
Acceptable fluid loss and air inclusion should be as
specified in the respective connector standard or as
agreed by the parties involved. Any deviation shall be
considered a test failure.
7.3 7.3 Apply a linear force or torque to the coupling half until complete connection occurs. During this
operation, the locking mechanism may be operated manually, if necessary, to permit normal coupling of the
halves.
7.4 7.4 Measure the connect force or connect torque or both, as appropriate.
7.5 7.5 Repeat the test for a total of five times on the same test assembly. Average the results of the
five tests to determine the connect force or torque. Report the average in the test report. This value is the rated
connect force or rated connect torque.
7.6 7.6 Report any failures identified in Table 4Table 4 (e.g. damage, malfunction, leakage) in the
test report.
8 Disconnect force or torque test
8.1 8.1 The instructions given in Annex BAnnex B on how to conduct this test shall be followed when
internal pressure is present in the coupling
8.2 8.2 Lubricate the coupling interfaces of the test assembly with the test fluid. Insert the test
assembly in a test fixture. Maintain the internal test pressure either as specified in the respective connector
standard or as agreed by the parties involved or in accordance with the prevailing flow conditions. Conduct
the test using the parameters and procedures given in Table 4Table 4.
8.3 8.3 Apply linear force or torque to the retaining mechanism of the coupling until disconnection
occurs.
8.4 8.4 Measure the disconnect force or torque, as appropriate.
8.5 8.5 Repeat the test for a total of five disconnections on the same test assembly. Average the test
results of the five tests to determine the disconnect force or torque. Report the average in the test report. This
value is the rated disconnect force or the rated disconnect torque.
8.6 8.6 Report any failures identified in Table 4Table 4 (e.g. damage, malfunction, leakage) in the
test report.
9 Leakage test
9.1 Low pressure, coupled
9.1.1 9.1.1 Insert the test assembly in a test apparatus, as shown in Figure 2Figure 2. Fill the test
apparatus with test fluid (5.4(see 5.4)) to a fluid column height of 750 mm. Apply a 50 N load perpendicular
to the coupling centreline at a distance of 10D from the centreline of the main interface seal, where D is the
nominal coupling size, in millimetres.

18869_ed2fig2.EPS
Key
1 inside diameter, maximum 13 mm
2 column with top portion graduated for measurement
3 plug coupling half
4 steel rod connected to the plug coupling half not held in the fixture
5 50 N load perpendicular to centreline of the coupling
6 centreline of the main interface seal (see detail)
7 fixture to hold the socket coupling half
8 socket coupling half
9 head fluid column
A section detail: first sealing element
D nominal size of the coupling
Figure 2 — Test apparatus for the low pressure leakage test, coupled
9.1.2 9.1.2 Measure the drop in column height over a minimum test period of 30 min. Calculate the leakage
rate in millilitres per hour.
9.1.3 9.1.3 Report the leakage rate in the test report.
9.2 Low–pressure, uncoupled (valved only)
9.2.1 9.2.1 Insert each coupling half into the test apparatus, as shown in Figure 3Figure 3. Fill the test
apparatus with test fluid (5.4(see 5.4)) to a fluid column height of 750 mm.
18869_ed2fig3.EPS
Key
1 inside diameter, maximum 13 mm
2 column with top portion graduated for measurement
3 coupling half (plug or socket) under test
4 top of column open to atmosphere
5 head fluid column
Figure 3 — Test apparatus for the low pressure leakage test, uncoupled
9.2.2 9.2.2 Measure the drop in column height over a test period of 30 min. Calculate the leakage rate in
millilitres per hour.
9.2.3 9.2.3 Report the leakage rate in the test report.
9.3 Maximum working pressure, coupled
9.3.1 9.3.1 Purge internal air from the circuit. Pressurize the coupling assembly with the test fluid at the
rated pressure or maximum pressure specified in the respective connector standard or as agreed by the
parties involved, and maintain this pressure level for a test period of 30 min.
9.3.2 9.3.2 During the test period, observe any leakage and collect and measure it in a graduated
measuring flask. Calculate the leakage rate in millilitres per hour.
9.3.3 9.3.3 Report the leakage rate in the test report.
9.4 Maximum working pressure, uncoupled (valved only)
9.4.1 9.4.1 Purge internal air from the circuit. Pressurize the coupling half with the test fluid at the rated
pressure or maximum pressure specified in the respective connector standard or as agreed by the parties
involved, and maintain this pressure level for a test period of 30 min.
9.4.2 9.4.2 During the test period, observe any leakage from each coupling half and collect and measure it
in a graduated measuring flask. Calculate the leakage rate in millilitres per hour.
9.4.3 9.4.3 Report the leakage rate in the test report.
10 Vacuum test
10.1 General
This procedure is recommended only for vacuum tests for which measurement of a leakage rate is not
required.
10.2 Coupled test
10.2.1 10.2.1 Insert the coupling assembly in a test apparatus as shown in Figure 4Figure 4.

18869_ed2fig4.EPS
Key
1 fixture to hold socket coupling half
2 coupling or coupling half under test
3 plug coupling half
4 steel rod connected to plug coupling half not held in the fixture
5 50 N load perpendicular to the centreline of the coupling under test
6 centreline of the main interface seal
7 socket coupling half
8 manometer
9 vacuum pump
10 valve
A section detail: first sealing element
D the nominal size of the coupling
L maximum 15D
NOTE Side load is applied only during the coupled test.
Figure 4 — Apparatus for vacuum test
10.2.2 10.2.2 Apply the side load to the coupling assembly, as shown in Figure 4Figure 4.
10.2.3 10.2.3 Start the vacuum pump and create a vacuum to the value specified in the respective connector
standard or as agreed by the parties involved.
10.2.4 10.2.4 Close the valve and allow 10 min for stabilization.
10.2.5 10.2.5 Observe the vacuum gauge for any loss of vacuum.
10.2.6 10.2.6 Report the gauge reading in the test report.
10.3 Uncoupled test (valved only)
10.3.1 10.3.1 Insert each coupling half in a test apparatus as shown in Figure 4Figure 4.
10.3.2 10.3.2 Start the vacuum pump and create a vacuum to the value specified in the respective connector
standard or as agreed by the parties involved.
10.3.3 10.3.3 Close the valve and allow 10 min for stabilization.
10.3.4 10.3.4 Observe the vacuum gauge for any loss of vacuum.
10.3.5 10.3.5 Report the gauge reading in the test report.
11 Air inclusion test
11.1 11.1 Insert the coupling assembly in a test apparatus as shown in Figure 5Figure 5. Record the
fluid level of the closed graduated cylinder, with the coupling connected and the fluid levels coincident.

18869_ed2fig5.EPS
Key
1 open-top vessel with fluid
2 mating coupling half
3 fixed coupling half
4 closed graduated vessel with test fluid
a
Reading shall be taken when fluid levels are coincident.
b
If an air bubble appears in this vessel, the test shall be rerun, because the air has come from air trapped in the coupling.
c
A lanyard may be used to prevent accidental dropping of the plug half below the 250 mm minimum requirement.
d
Difference in the volume of entrapped air represents the total air inclusion.
Figure 5 — Apparatus for the air inclusion test
11.2 11.2 Uncouple and couple the coupling assembly and allow lost fluid to drain after uncoupling. After
each uncoupling/coupling cycle, tap the coupling assembly to clear all air bubbles from the interior of the
assembly.
11.3 11.3 Repeat the procedures specified in 11.211.2 until the fluid displaced by air in the graduated
cylinder exceeds 10 minor divisions on the graduated scale. With the coupling coupled, adjust the open-top
vessel vertically so that the fluid levels are coincident. Record the fluid level of the graduated cylinder.
11.4 11.4 Subtract the fluid level value recorded in 11.311.3 from the value recorded in 11.111.1 and
divide the difference by the number of coupling/uncoupling cycles.
11.5 11.5 Report the air inclusion in millilitres per coupling/uncoupling cycle in the test report.
12 Fluid loss test
12.1 12.1 Insert the coupling assembly in a test apparatus as shown in Figure 6Figure 6. Maintain a
fluid pressure of 0,1 MPa (1 bar) in the graduated vessel with test fluid. If the viscosity of the test fluid prevents
prompt clearing of bubbles, use a fluid with a lower viscosity and record the fluid type used. Record the fluid

level of the graduated vessel.

18869_ed2fig6.EPS
Key
1 graduated vessel with test fluid
2 Y connector
3 rigid tubing
4 polytetrafluorethylene (PTFE) tubing
5 mating coupling half
6 fixed coupling half
a
Fluid pressure inlet.
Figure 6 — — Apparatus for the fluid loss test
12.2 12.2 Couple and uncouple the assembly. After each uncoupling, allow the fluid loss to drain from the
assembly. After each coupling, tap the assembly to clear all air bubbles from the interior of the coupling.
12.3 12.3 Repeat the procedures in 12.212.2 until the fluid level of the graduated vessel has dropped a
minimum of 10 minor divisions on the scale. Record the fluid level of the graduated vessel.
12.4 12.4 Subtract the fluid level value recorded in 12.312.3 from the value recorded in 12.112.1 and
divide the difference by the number of coupling/uncoupling cycles.
12.5 12.5 Report the value calculated in 12.412.4 as the fluid loss in millilitres per coupling/uncoupling
cycle in the test report (, S ).
nc
13 Pressure drop (, Δp), test
13.1 13.1 Insert the test coupling in a test apparatus as shown in Figure 7Figure 7;; the pressure tap
shall be in accordance with ISO 4411, classes of measurement accuracy B and C. Select at least six flow rates
from 25 % to 150 % of the rated flow, including 100 % of rated flow. If the rated flow is not specified in the
respective connector standard, use the values given in Table 5Table 5.
18869_ed2fig7.EPS
Key
1 coupling under test
2 pressure tap
3 differential pressure measuring device
4 controlled fluid supply
NOTE Dimensions L1 to L5 are minimum lengths:
L 10 times the inside diameter of the coupling tube or pipe;
L2 5 times the inside diameter of the coupling tube or pipe;
L3 length of the coupling plus end fittings;
L 10 times the inside diameter of the coupling tube or pipe;
L5 5 times the inside diameter of the coupling tube or pipe; as alternative the flow meter can be positioned at the beginning of
L1;.
Figure 7 — Apparatus for the pressure drop test
Table 5 — Typical rated flows
Coupling size Rated flow
(nominal hose size) Q
R
mm l/min
3,2 3
5 6
6,3 12
10 23
12,5 45
16 74
19 (20) 100 (106)
25 189
31,5 288
38 (40) 342 (379)
51 (50) 788(757)
13.2 13.2 Determine and record the pressure drop of the test coupling in plug-half-to-socket-half and
socket -half-to-plug-half directions, at the flow rates selected in 13.113.1.
13.3 13.3 Remove the test coupling from the test apparatus and connect the tubes or pipes using an
appropriate adaptor with the same or shorter length than the tested coupling and the same inside diameter
as the tubes or pipes to ensure the continuity of the internal geometry. Determine and record the pressure
drop at the same flow rates selected in 13.113.1.
2 2
13.4 13.4 Maintain the viscosity of the test fluid at 28,8 mm /s to 35,2 mm /s throughout the test.
Record the fluid type and temperature.
13.5 13.5 Subtract the pressure drop values obtained in 13.313.3 from those obtained in 13.213.2.
The difference is the net pressure drop of the test coupling. Graphically plot the net pressure drop for each
flow direction. Full logarithmic graphing is recommended in order to obtain a straight line. It is not necessary
for the line to pass through the points, but it should represent common values between the points.
13.6 13.6 If the pressure drop values in any one flow rate in one direction of flow through the coupling
differ by less than 10 %, referred to the rated flow, from the pressure drop in the other direction of flow
through the coupling, the higher of the two values shall be used.
If the pressure drop values in any one flow rate in one direction of flow through the coupling differ by more
than 10 %, referred to the rated flow, from the pressure drop in the other direction of flow through the
coupling, the higher or both values shall be used.
13.7 13.7 Attach the plot to the test report.
14 Static pressure test
14.1 Coupled
14.1.1 14.1.1 Pressurize the coupling to specified static pressure for a minimum of 5 min.
14.1.2 14.1.2 Determine the leakage rate in accordance with 9.19.1 and 9.39.3.
14.1.3 14.1.3 Connect and disconnect the coupling five times at zero pressure.
14.1.4 14.1.4 Record any evidence of malfunction.
14.1.5 14.1.5 Report the leakage rate in the test report.
14.2 Uncoupled (valved type only)
14.2.1 14.2.1 Pressurize the uncoupled halves to the specified static pressure for a minimum of 5 min.
14.2.2 14.2.2 Determine the leakage rate in accordance with 9.29.2 and 9.49.4.
14.2.3 14.2.3 Record any evidence of malfunction.
14.2.4 14.2.4 Report the leakage rate in the test report.
15 Specific temperature test
15.1 Maximum working temperature exposure
15.1.1 General
These tests shall be conducted at the maximum working temperature.
The tests specified in 15.1.215.1.2 and 15.1.315.1.3 might require specific and dedicated
a) a) safety instructions to prevent injury to persons and damage to the environment, and
b) b) ambient and environnemental conditions.
Any precautions shall be taken for testing conducted in both the coupled and uncoupled position.
15.1.2 Coupled
15.1.2.1 Fill the coupling assembly with test fluid and subject the assembly to the maximum working
temperature for a minimum of 6 h. The coupling shall be internally vented to atmosphere during the
temperature adjustment.
15.1.2.11.1.1.1 15.1.2.1 Fill the coupling assembly with test fluid and subject the
assembly to the maximum working temperature for a minimum of 6 h. The coupling shall be internally vented
to atmosphere during the temperature adjustment.
15.1.2.2 15.1.2.2 Allow the coupling to cool to ambient temperature. Disconnect and reconnect
the coupling. Determine the leakage rate in accordance with 9.19.1 and 9.39.3. If it is necessary that the
connecting and disconnecting take place at a certain temperature, this temperature should be agreed by the
parties involved.
15.1.2.3 15.1.2.3 Report the leakage rate in the test report.
15.1.3 Uncoupled (valved only)
15.1.3.1 Fill the coupling halves with test fluid and subject the halves to the maximum working temperature
for a minimum of 6 h.
15.1.3.11.1.1.1 15.1.3.1 Fill the coupling halves with test fluid and subject the halves to
the maximum working temperature for a minimum of 6 h.
15.1.3.2 15.1.3.2 Allow the coupling to cool to ambient temperature and actuate the valves
manually five times to separate the valve seal from the sealing surface. Determine the leakage rate in
accordance with 9.29.2 and 9.49.4.
15.1.3.3 15.1.3.3 Report the leakage rate in the test report.
15.2 Maximum working temperature service
15.2.1 Coupled
15.2.1.1 Fill the coupling assembly with test fluid and subject the assembly to the maximum working
temperature for a minimum of 6 h. The coupling shall be internally vented to atmosphere during the
temperature adjustment.
15.2.1.11.1.1.1 15.2.1.1 Fill the coupling assembly with test fluid and subject the
assembly to the maximum working temperature for a minimum of 6 h. The coupling shall be internally vented
to atmosphere during the temperature adjustment.
15.2.1.2 15.2.1.2 Determine the leakage rate in accordance with 9.19.1 and 9.39.3.
15.2.1.3 15.2.1.3 Report the leakage rate in the test report.
15.2.2 Uncoupled (valved only)
15.2.2.1 Fill the coupling halves with test fluid and subject the halves to the maximum working temperature
for a minimum of 6 h.
15.2.2.11.1.1.1 15.2.2.1 Fill the coupling halves with test fluid and subject the halves to
the maximum working temperature for a minimum of 6 h.
15.2.2.2 15.2.2.2 Determine the leakage rate in accordance with 9.29.2 and 9.49.4.
15.2.2.3 15.2.2.3 Report the leakage rate in the test report.
15.3 Minimum working temperature
15.3.1 Coupled
15.3.1.1 15.3.1.1 Fill the coupling assembly with test fluid and subject the assemb
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