EN ISO 15620:2019

SLOVENSKI STANDARD
01-september-2019
Nadomešča:
SIST EN ISO 15620:2002
Varjenje - Torno varjenje kovinskih materialov (ISO 15620:2019)
Welding - Friction welding of metallic materials (ISO 15620:2019)
Schweißen - Reibschweißen von metallischen Werkstoffen (ISO 15620:2019)
Soudage - Soudage par friction des matériaux métalliques (ISO 15620:2019)
Ta slovenski standard je istoveten z: EN ISO 15620:2019
ICS:
25.160.10 Varilni postopki in varjenje Welding processes
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO 15620
EUROPEAN STANDARD
NORME EUROPÉENNE
June 2019
EUROPÄISCHE NORM
ICS 25.160.10 Supersedes EN ISO 15620:2000
English Version
Welding - Friction welding of metallic materials (ISO
15620:2019)
Soudage - Soudage par friction des matériaux Schweißen - Reibschweißen von metallischen
métalliques (ISO 15620:2019) Werkstoffen (ISO 15620:2019)
This European Standard was approved by CEN on 30 May 2019.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2019 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 15620:2019 E
worldwide for CEN national Members.

Contents Page
European foreword . 3
Annex ZA (informative) Relationship between this European Standard and the essential
requirements of EU Directive 2014/68/EU (PED) aimed to be covered . 4

European foreword
This document (EN ISO 15620:2019) has been prepared by Technical Committee ISO/TC 44 "Welding
and allied processes" in collaboration with Technical Committee CEN/TC 121 “Welding and allied
processes” the secretariat of which is held by DIN.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by December 2019, and conflicting national standards
shall be withdrawn at the latest by December 2019.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN ISO 15620:2000.
This document has been prepared under a mandate given to CEN by the European Commission and the
European Free Trade Association, and supports essential requirements of EU Directive(s).
For the relationship with EU Directive(s) see informative Annex ZA, which is an integral part of this
document.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the
United Kingdom.
Endorsement notice
The text of ISO 15620:2019 has been approved by CEN as EN ISO 15620:2019 without any modification.

Annex ZA
(informative)
Relationship between this European Standard and the essential
requirements of EU Directive 2014/68/EU (PED) aimed to be covered
This European Standard has been prepared under a Commission's standardization request M/071
"Mandate to CEN for standardization in the field of pressure equipment" to provide one voluntary
means of conforming to essential requirements of Directive 2014/68/EU (PED) on the harmonisation of
the laws of the Member States relating to the making available on the market of pressure equipment.
Once this standard is cited in the Official Journal of the European Union under that Directive,
compliance with the normative clauses of this standard given in Table ZA.1 confers, within the limits of
the scope of this standard, a presumption of conformity with the corresponding essential requirements
of that Directive, and associated EFTA regulations.
Table ZA.1 — Correspondence between this European Standard and Annex I of the Directive
2014/68/EU (PED)
Essential Requirements of Clauses of this EN Remarks/Notes
Directive 2014/68/EU (PED)
Annex I, 3.1 Clause 4 Welding procedures
Welding components quality and
Annex I, 3.1.1 Sub-clauses 5.1, 5.2, 5.4
preparation
Annex I, 3.1.4 Sub-clause 5.3 Heat treatment
Annex I, 3.1.2 – paragraphs Welding procedure specification
Clauses 6, 7, 8
1,2,3 and approval, welding personnel
WARNING 1 — Presumption of conformity stays valid only as long as a reference to this European
Standard is maintained in the list published in the Official Journal of the European Union. Users of this
standard should consult frequently the latest list published in the Official Journal of the European
Union.
WARNING 2 — Other Union legislation may be applicable to the product(s) and services falling within
the scope of this standard.
INTERNATIONAL ISO
STANDARD 15620
Second edition
2019-05
Welding — Friction welding of
metallic materials
Soudage — Soudage par friction des matériaux métalliques
Reference number
ISO 15620:2019(E)
©
ISO 2019
ISO 15620:2019(E)
© ISO 2019
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
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below or ISO’s member body in the country of the requester.
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Fax: +41 22 749 09 47
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Published in Switzerland
ii © ISO 2019 – All rights reserved

ISO 15620:2019(E)
Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Welding knowledge . 3
4.1 Process . 3
4.1.1 General. 3
4.1.2 Direct drive rotational friction welding . 4
4.1.3 Stored energy (inertia) friction welding . 6
4.1.4 Further processes . 8
4.1.5 Friction welding arrangements . 8
4.2 Materials and material combinations . 8
4.3 Friction welding machines. 9
4.3.1 General. 9
4.3.2 Features .10
5 Quality requirements .10
5.1 General .10
5.2 Pre-welding requirements .10
5.2.1 Condition of raw materials . .10
5.2.2 Preparation of the components to be welded . .11
5.2.3 Component holding .11
5.3 Post-welding treatment .11
5.4 Quality assurance.11
6 Welding procedure specification (WPS) .12
6.1 General .12
6.2 Information related to the manufacturer .12
6.3 Information related to the material .13
6.4 Welding parameters .13
6.5 Joint .13
6.6 Optional devices .13
7 Welding procedure approval .13
7.1 Principles .13
7.2 Welding procedure tests .14
7.2.1 Application .14
7.2.2 Preliminary welding procedure specification (pWPS) .14
7.2.3 Number of test weldments .14
7.2.4 Specification for test specimens .14
7.2.5 Test procedures.16
7.2.6 Acceptance criteria .18
7.3 Welding procedure approval record (WPQR) .18
7.4 Previous experience .18
7.5 Circumstances mandating requalification .18
7.6 Machine-specific nature of a WPS .19
7.7 Requalification procedure requirements .19
8 Welding personnel.19
8.1 Friction welding machine operator.19
8.2 Friction welding machine setter .19
8.3 Welding coordination personnel (supervisor) .19
Annex A (informative) Relationship of welding parameters .20
ISO 15620:2019(E)
Annex B (informative) Additional processes based on friction .22
Annex C (informative) Material combinations weldable by friction welding .25
Annex D (informative) Guidelines for quality assurance .27
Annex E (informative) Examination and test .28
Annex F (informative) Manufacturer's friction welding procedure specification (WPS) .30
Annex G (informative) Characteristics of friction welded components .32
Annex H (informative) Welding procedure approval record form (WPQR) Welding
procedure approval — Test certificate .37
Bibliography .40
iv © ISO 2019 – All rights reserved

ISO 15620:2019(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see www .iso
.org/iso/foreword .html.
This document was prepared by Technical Committee ISO/TC 44, Welding and allied processes,
Subcommittee SC 10, Quality management in the field of welding.
Any feedback, question or request for official interpretation related to any aspect of this document
should be directed to the Secretariat of ISO/TC 44/SC 10 via your national standards body. A complete
listing of these bodies can be found at www .iso .org/members .html. Official interpretations, where they
exist, are available from this page: https: //committee .iso .org/sites/tc44/home/interpretation .html.
This second edition cancels and replaces the first edition (ISO 15620:2000), which has been technically
revised.
The main changes compared to the previous edition are as follows:
— Clause 2 has been updated;
— in Clause 3, terms not used in the text have been deleted;
— in Annex B of 4 processes based on friction have been added;
— the recommended test to perform on test weld has been clarified (addition of Table 4).
ISO 15620:2019(E)
Introduction
Friction welding is a method for making welds in the solid phase in which one component is moved
relative to and in pressure contact with the mating component to produce heat at the faying surfaces,
the weld being completed by the application of a force during or after the cessation of relative motion.
There are several forms of supplying energy and various forms of relative movements.
The generation of friction heating results in a comparatively low joining temperature at the interface.
This is largely the reason why friction welding is suitable for materials and material combinations
which are otherwise difficult to weld. The weld region is generally narrow and normally has a refined
microstructure.
While the friction welding process deals primarily with components of circular cross-section it does
not preclude the joining of other component shapes.
vi © ISO 2019 – All rights reserved

INTERNATIONAL STANDARD ISO 15620:2019(E)
Welding — Friction welding of metallic materials
1 Scope
This document specifies requirements for the friction welding of components manufactured from metals.
It specifies requirements particular to rotational friction welding related to welding knowledge, quality
requirements, welding procedure specification, welding procedure approval and welding personnel.
This document is appropriate where a contract, an application standard or a regulatory requirement
requires the demonstration of the manufacturer's capability to produce welded constructions
of a specified quality. It has been prepared in a comprehensive manner to be used as a reference in
contracts. The requirements given can be adopted in full or some can be deleted, if not relevant to the
construction concerned.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological database for use in standardization at the following addresses:
— ISO Online browsing platform: available at https: //www .iso .org/obp
— IEC Electropedia: available at http: //www .electropedia .org/
3.1
axial force
force in axial direction between components to be welded
3.2
burn-off length
loss of length during the friction phase
3.3
burn-off rate
rate of shortening of the components (3.4) during the friction welding process
3.4
component
single item before welding
3.5
component induced braking
reduction in rotational speed (3.18) resulting from friction between the interfaces
3.6
external braking
braking located externally reducing the rotational speed (3.18)
ISO 15620:2019(E)
3.7
faying surface
surface of one component (3.4) that is to be in contact with a surface of another component (3.4) to
form a joint
3.8
forge force
force applied normal to the faying surfaces (3.7) at the time when relative movement between the
components (3.4) is ceasing or has ceased
3.9
forge burn-off length
amount by which the overall length of the components (3.4) is reduced during the application of the
forge force (3.8)
3.10
forge phase
interval time in the friction welding cycle between the start and finish of application of the forge
force (3.8)
3.11
forge pressure
pressure (force per unit area) on the faying surfaces (3.7) resulting from the axial forge force (3.8)
3.12
forge time
time for which the forge force (3.8) is applied to the components (3.4)
3.13
friction force
force applied perpendicularly to the faying surfaces (3.7) during the time that there is relative movement
between the components (3.4)
3.14
friction phase
interval time in the friction welding cycle in which the heat necessary for making a weld is generated
by relative motion and the friction force(s) (3.13) between the components (3.4), i.e. from contact of
components (3.4) to the start of deceleration
3.15
friction pressure
pressure (force per unit area) on the faying surfaces (3.7) resulting from the axial friction force
3.16
friction time
time during which relative movement between the components (3.4) takes place at rotational speed
(3.18) and under application of the friction force(s) (3.13)
3.17
interface
contact area developed between the faying surfaces (3.7) after completion of the welding operation
3.18
rotational speed
number of revolutions per minute of rotating component (3.4)
3.19
stick-out
distance a component (3.4) sticks out from the fixture, or chuck in the direction of the mating
component (3.4)
2 © ISO 2019 – All rights reserved

ISO 15620:2019(E)
3.20
deceleration phase
interval in the friction welding cycle in which the relative motion of the components (3.4) is
decelerated to zero
3.21
deceleration time
time required by the moving component (3.4) to decelerate from friction speed to zero speed
3.22
total length loss (upset)
loss of length that occurs as a result of friction welding, i.e. the sum of the burn-off length (3.2) and the
forge burn-off length (3.9)
3.23
total weld time
time elapsed between component (3.4) contact and end of forging phase
3.24
welding cycle
succession of operations carried out by the machine to make a weldment and return to the initial
position, excluding component (3.4) - handling operations
3.25
weldment
two or more components joined by welding
4 Welding knowledge
4.1 Process
4.1.1 General
The classification of friction welding processes is listed in Table 1.
ISO 15620:2019(E)
Table 1 — Classification of friction welding processes
4.1.2 Direct drive rotational friction welding
The energy input is provided by direct drive at predetermined rotational speed or speeds (see Figure 1
and Figure 2).
4 © ISO 2019 – All rights reserved

ISO 15620:2019(E)
Key
1 drive motor
2 brake
3 rotating clamp
4 stationary clamp
5 rotating workpiece
6 stationary workpiece
7 forge cylinder
Figure 1 — Diagram showing direct drive rotational friction welding
ISO 15620:2019(E)
Key
a
1 axial force Burn-off length.
b
2 axial displacement Friction time.
c
3 rotational speed Deceleration time.
d
4 friction phase Forge time.
e
5 friction force Forge burn-off length.
f
6 deceleration phase Total length loss (upset).
7 forge phase
8 forge force
Figure 2 — Diagram showing typical relationships of characteristics for friction welding at
constant rotational speed (friction welding, process No. 42 in accordance with ISO 4063)
The spindle is either decelerated at a predetermined rate or stopped by external braking or component
induced braking. The main welding parameters are listed below and their relationship is given in
Annex A:
— rotational speed(s);
— predetermined friction force(s);
— friction time or burn-off;
— predetermined forge force(s);
— forge time;
— deceleration time and forge delay.
4.1.3 Stored energy (inertia) friction welding
Energy stored in an inertia mass is used up in the friction welding process by component induced
braking (see Figure 3 and Figure 4).
6 © ISO 2019 – All rights reserved

ISO 15620:2019(E)
Key
1 drive motor
2 inertia mass, variable
3 rotating clamp
4 stationary clamp
5 rotating workpiece
6 stationary workpiece
7 forge cylinder
Figure 3 — Diagram showing inertia friction welding
Key
1 axial force 6 forge phase
2 axial displacement 7 forge force
a
3 rotational speed Total length loss (upset).
b
4 friction phase Friction time.
c
5 friction force Forge time.
Figure 4 — Diagram showing typical relationships of characteristics for inertia friction welding
(friction welding, process No. 42 in accordance with ISO 4063)
ISO 15620:2019(E)
The main welding parameters are listed below and their relationship is given in Annex A:
— rotational speed;
— inertia mass;
— predetermined friction force(s);
— predetermined forge force(s).
4.1.4 Further processes
Further processes are listed in Annex B.
4.1.5 Friction welding arrangements
The following methods of rotational friction welding (see Figure 5) can be distinguished:
— friction welding with the rotation of one of the components to be welded and linear movement of the
other [Figure 5 a)], i.e. with a fixed head friction welding machine;
— welding with rotation and linear movement of one of the components to be welded and the other one
held static [Figure 5 b)] i.e. with a sliding head friction welding machine;
— rotation and linear movement of two components against a static middle component [Figure 5 c)]
i.e. with a double ended friction welding machine;
— rotation of central component with linear movement of two end components [Figure 5 d)].
a) b) c) d)
Figure 5 — Rotational friction welding methods
4.2 Materials and material combinations
Experience of friction welding many metallic materials and combinations is already well-documented
(see Annex C). Weldability criteria for other welding processes is not always valid for friction welding.
More materials and their combinations can be friction welded when compared with most other welding
processes. The data shown in Annex C is based upon actual experience from test welds but it is not
necessarily complete. For many materials and material combinations, there is further data available
which is only valid for particular geometries.
The following factors can affect welding quality:
— amount, distribution and shape of non-metallic inclusions in the parent material(s);
— formation of intermetallic phases in the weld;
— formation of low melting point phases in the weld;
— porosity in parent material(s);
— thermal softening of hardened materials in the weld;
— hardening of the weld metal heat affected zone;
8 © ISO 2019 – All rights reserved

ISO 15620:2019(E)
— hydrogen in parent material(s).
It can be possible to negate some of the above by critical selection of parameters or heat treatment.
4.3 Friction welding machines
4.3.1 General
Friction welding is not sensitive to position and can be performed in any plane.
Machine design and build are dependent upon the welding application and there are preconditions
for exact and repeatable production. A schematic diagram of a horizontal friction welding machine is
shown in Figure 6.
Key
1 machine frame 7 flash removal unit
2 headstock with drive spindle and brake 8 safety guards
3 chuck - for rotating component 9 hydraulic power pack - not shown
4 clamp - for fixed component 10 electrical control cabinet - not shown
5 machine slides (tie-bars) 11 machine control panel
6 force actuator
Figure 6 — Schematic diagram of a direct drive friction welding machine of horizontal
configuration
The application determines the choice of axial force(s), rotation speed(s) and welding time. Other
parameters which affect machine design are carriage speed during friction, friction burn-off, braking
point, forging point, torque and moment of inertia of the rotating mass.
The repeatability and variation of machine parameters should be checked while the machine is running
at operating temperature.
The machine should be of a specification appropriate to the parts to be welded.
ISO 15620:2019(E)
The machine should be equipped with an automatic control system which, after the components have
been clamped in their work-holding devices and on initiation of the cycle, undertakes a controlled welding
cycle without intervention from the operator and incorporates at least the following operational cycle:
— initiation of a sequence which brings the components into face contact at a chosen rotational speed;
— establishment and the maintenance of a friction force(s) and relative speed(s) for the duration of the
heating cycle;
— establishment and maintenance of the forge force for a desired forge time or forge distance or
combination of both, to complete the weldment.
Unclamping the work-holding devices can be done automatically or not, thus completing the cycle of
operations.
4.3.2 Features
Friction welding machines can be equipped with the following options:
— loading equipment;
— unloading equipment;
— turning units for facing, flash removal, machining;
— shearing unit to strip the flash;
— extended memory for welding programmes;
— weld identification unit;
— angular orientation;
— monitoring;
— identification;
— in process proof testing.
5 Quality requirements
5.1 General
The regulations and recommendations which govern other welding processes apply only in part to
friction welding.
Emphasis should be placed on the avoidance of imperfections rather than on developing methods to
find them. An important prerequisite for ensuring weld quality is the uniformity and consistency of the
component to be welded. For this reason, adequate quality assurance measures shall be taken during
the pre-welding, welding and post-welding process operations.
5.2 Pre-welding requirements
5.2.1 Condition of raw materials
To ensure repeatable properties of friction welds which remain constant within a friction welding
series, the following conditions should be maintained:
— chemical analysis;
— structure;
10 © ISO 2019 – All rights reserved

ISO 15620:2019(E)
— strength and hardness;
— dimensional and geometrical tolerances;
— supply conditions of the materials to be joined.
5.2.2 Preparation of the components to be welded
Unless otherwise required by the design specification, the following should be adhered to:
— The end of each component shall be prepared so that the faying surface lies in a plane at right angles
to the axis of rotation, the end being cut square. This end can be tapered if required so that the area
of the faying surface is reduced for the early stage of the welding cycle. The length of the taper shall
be not greater than 50 % of the burn-off length for each component and sufficient to ensure that
the plane of the weld interface is on the parallel portion of the component, or at such a position as is
indicated on the drawing agreed between the contracting parties.
— Dirt, grease, rust and other surface oxides or protective films shall be removed from the faying
surfaces before the components are placed in the machine, except where surface contamination is
shown to have no detrimental effect on joint properties.
— Surface irregularities on the faying surface, e.g. centre turning holes, shall only be allowed where
they do not cause harmful effects.
5.2.3 Component holding
The torque and axial forces resulting from the friction welding cycle are normally resisted by the tooling.
The clamping force shall be not so great as to deform or mark the components beyond acceptable levels.
Suitable backstops are used wherever possible to prevent axial slippage. Plugs may be used to provide
additional support when gripping hollow components.
The components to be welded shall be set in the machine so that their axes lie within the limits specified
for concentricity and alignment.
To achieve the required alignment, it is sometimes necessary to machine or clean the surfaces of the
components to be clamped.
Particular care is necessary with regard to tooling and alignment when welding hollow sections having
an outside dimension that is large relative to the wall thickness of the component.
The stick-out shall not be so short as to cause unacceptable chilling of the component or so long as to
cause unacceptable misalignment or vibration of the opposing faces during the friction and forge phases.
The two components should be clamped wherever possible so that the stick-out of each is equal, unless
the difference in composition or size of the two components makes it desirable for them to have different
sticks-out, either to achieve a heat balance or to permit effective work holding.
5.3 Post-welding treatment
Where necessary, further procedures as machining and/or post-weld heat treatment of friction welds
shall be carried out in accordance with the expected environmental operating conditions.
5.4 Quality assurance
The system of quality control employed shall take into consideration the following factors:
— production rate and batch size;
— size and design of weldments;
ISO 15620:2019(E)
— economic considerations;
— intended operating conditions.
The system employed shall be sufficient to ensure that consistent and satisfactory weld quality is
maintained on a batch or individual basis.
The system should ensure that procedures are in place to ensure regular calibration of the friction
welding machine.
Production quality control records shall be kept, the form and content of which shall be agreed between
the contracting parties.
Guidelines for the level of quality assurance to be used are given in Annex D.
Whether destructive or non-destructive testing methods can be applied depends on the special use of
the welded components. A list of destructive and non-destructive testing methods which are generally
suitable for friction welding is appended in Annex E. Possible testing procedures are given to facilitate
the choice of the most appropriate method.
6 Welding procedure specification (WPS)
6.1 General
The welding procedure specification (WPS) shall give details of how a welding operation is to be
performed and shall contain all relevant information about the welding work.
Welding procedure specifications may cover a certain range of cross-sectional areas. Additionally, some
manufacturers can prefer to prepare work instructions for each specific job as part of the detailed
production planning.
Components used for WPS qualification purposes shall be representative of those used for actual
production components in the following respects:
— chemistry;
— faying surface condition;
— heat treatment;
— joint geometry/dimensions.
The information listed below is adequate for most welding operations. For some applications, it can be
necessary to supplement or reduce the list. The relevant information shall be specified in the WPS.
Ranges and tolerances, according to the manufacturer's experience, shall be specified where
appropriate.
An example of a recommended WPS-format is shown in Annex F.
6.2 Information related to the manufacturer
— Identification of the manufacturer: unique identification;
— Identification of the WPS: alphanumeric designation (reference code) related to a specific friction
welding machine.
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ISO 15620:2019(E)
6.3 Information related to the material
— Material type: identification of the material, preferably by reference to an appropriate standard.
A WPS can cover a group of materials, if agreed prior to production, see 7.1.
— Component information:
— geometry;
— dimensions;
— chemical analysis;
— other relevant information.
6.4 Welding parameters
All relevant parameters shall be listed (see Clause 4 and Annex F).
6.5 Joint
— Joint design: a sketch of the joint design showing position of weld(s), details and tolerances may
be made.
— Preparation of components: selected method of surface preparation, as necessary (e. g. sawing,
turning).
— Fixtures:
— the methods to be used;
— details of fixtures and backstops.
6.6 Optional devices
For example, flash forming, supports when welding thin-walled tubes.
7 Welding procedure approval
7.1 Principles
The following procedure is designed to meet high duty applications.
Welding procedure specifications for friction welding shall be approved prior to production whenever
required. The methods of approval are:
— approval by welding procedure test according to 7.2;
— approval based on previous experience according to 7.4.
This document does not invalidate previous welding procedure approvals made to specifications
providing the intent of the technical requirements is satisfied and the previous procedure approvals
are relevant to the application and production work on which they are to be employed. Consideration of
previous procedure approvals to former national standards or specifications should be, at the time of
enquiry or contract stage, agreed between the contracting parties.
ISO 15620:2019(E)
7.2 Welding procedure tests
7.2.1 Application
When procedure tests are required, tests shall be carried out:
— in accordance with the application standard
— or according to-the provisions of 7.2.3 to 7.2.6 if no application standard is available.
7.2.2 Preliminary welding procedure specification (pWPS)
The preliminary welding procedure specification shall be prepared in accordance with Clause 6.
7.2.3 Number of test weldments
Unless more severe tests are required by the design specification or by other standards, the minimum
test requirements are as follows:
— a minimum of two weldments shall be produced for WPS qualification;
— a minimum of two weldments shall be evaluated.
If one of the test specimens has failed a defined acceptance criteria, then the welding conditions shall
be redetermined in order to satisfy the accepted criteria and further two tests specimens shall be
evaluated.
Alternative tests can be performed in some cases. The selection of test types and the number of test
specimens depend on the performance, safety and quality requirements of the component and assembly
and shall be established before any qualification is undertaken. Examples are given in 7.2.5.2.
7.2.4 Specification for test specimens
7.2.4.1 Solid sections — Specimens from bar to bar weldments for bend test
The weld shall be dressed flush, unless otherwise agreed by the test specification, having a surface
finish that does not affect the result. When components of differing sections are welded together, the
larger section shall be reduced to equal that of the smaller after welding.
Specim
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