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What’s new in ISO 15614-1:2017?
Introduction
The long-awaited revision of ISO 15614 Part 1, the ISO standard for the qualification of arc and gas welding procedures for steels and Nickel alloys, was
completed in the first half of 2017. The new version of the standard was published during June of the same year as ISO 15614-1:2017 and adopted by
BSI as BS EN ISO 15614-1:2017. This superseded BS EN ISO 15614-1:2004+A2:2012, which was withdrawn.
The 2017 version of the standard is the result of an extensive and lengthy revision process completed by the ISO /TC 44/SC 10 subcommittee and differs
significantly from the previous version in format, with some major changes in technical
content. This article presents the most significant differences
between the 2017 and the previous version of the standards, explains the rationale behind the changes and provides practical guidance on how to deal
with them.
Questions on the application of clauses of ISO 15614-1 that are not described here, as well as on other welding-related standards, can be submitted via
TWI’s
technical enquiry form.
DISCLAIMER - TWI is not authorised to give official interpretations of BS EN ISO standards. The views and opinions expressed in this article are those of
the authors and do not reflect the official policy or position of ISO, CEN or BSI. This article is not to be taken as a substitute for the standard, which must
be consulted where its application is required. No liability rests with TWI for any damages arising from the content of this article.
New: welding procedure test levels
The main change is that ISO 15614-1:2017 includes two levels of welding procedure tests, designated by levels 1 and 2. Level 1 is based on
requirements of Section IX of the ASME Boiler and Pressure Vessel Code (ASME IX) and Level 2 is based on the previous issues of ISO 15614-1.
In recent years, various industry sectors and standard development organisations have been pushing towards harmonisation and convergence between
international standards, including those for welding qualifications. At the start of the revision process, the relevant ISO subcommittee carried out a
comparison between corresponding requirements in ISO 15614-1 and ASME IX to evaluate the possibility to develop a ‘one-size-fits-all’ standard. This
exercise showed that the differences were such that these two standards could not be merged into one, hence the decision to include a two-level
approach.
The introduction to the standard explains that this approach was introduced “in order to permit application to a wide range of welded fabrication”. In
Level 2, the extent of testing is greater and the ranges of qualification are more restrictive than in Level 1. Hence, procedure tests carried out to Level 2
automatically qualify for Level 1 requirements, but not vice-versa. It should also be noted that when no level is specified in a contract or application
standard, the requirements for Level 2 apply.
As explained in the UK National Foreword to BS EN ISO 15614-1:2017, during the development of this standard, the UK committee voted against its
approval. The UK committee was concerned that the format of the standard (two levels being presented side-by-side, mixed with text common to both
levels) may cause a problem when working to either of the two welding procedure test levels. Users are warned that, as the requirements of the two
levels are often specified in the same clause, vigilance is required to identify the testing requirements and the range of qualification for the particular
welding procedure test level.
What happens to previous welding procedure qualifications?
The validity of previous welding procedure qualifications is addressed in different Sections of ISO 15614-1:2017, as follows:

Introduction: “All new welding procedure tests are to be carried out in accordance with this document from the date of its issue. However, this
document does not invalidate previous welding procedure tests made to former national
standards or specifications or previous issues of this
document”

Section 1: “Specification and qualification of welding procedures that were made in accordance with previous editions of this document may be used
for any application for which the current edition is specified. In this case, the

ranges of qualification of previous editions remain applicable”
Section 1: “It is also possible to create a new welding procedure qualification record (WPQR) range of qualification according to this edition based on
the existing qualified WPQR, provided the technical intent of the testing requirements
of this document has been satisfied. Where additional tests
have to be carried out to make the qualification technically equivalent, it is only necessary to perform the additional test on a test piece”
In other words:

Previous welding procedure qualifications remain valid and the ranges of qualification stay the same, even when ISO 15614-1:2017 applies.

Nevertheless, when contracts make reference to ISO 15614-1:2017 and a manufacturer wishes to apply an existing WPQR, the authors recommend
that manufacturers integrate the existing WPQR with an alignment sheet, showing the new ranges of qualification according to ISO 15614-1:2017.
Main technical changes and their background
A description of the main technical changes is given in the table below. This also includes an explanation of the rationale behind the changes and how
these affect existing and future welding procedure qualifications.
The table focuses on the difference between Level 2 requirements and the corresponding requirements in the previous edition of ISO 15614-1. Level 1
requirements, based on ASME IX, are not discussed.
IMPORTANT: the table is limited to the most significant changes, in the authors’ opinion, between ISO 15614-1:2017 (Level 2) and the previous edition.
It includes brief descriptions of variables and clauses and it cannot substitute the standard. Users must consult the standard when its application is
required.
Comparison between ISO 15614-1: 2004+A2:2012
and ISO 15614-1:2017 (Level 2).
ISO 15614-1:
2004+A2:2012
ISO
156141:2017
Reason for change and main
consequences
Clause/table (ISO 15614:2017): 1 Introduction
Two welding 
procedure
test levels:
Level 2:
applicable to a wider range of applications
In the absence of specific requirements, Level 2
applies
Existing WPQRs and qualification ranges remain
valid
New WPQRs according to ISO 15614-1:2017
can be issued, based on existing WPQRs
based on
previous ISO
15614-1
provided the technical intent of the testing
requirements of ISO 15614-1:2017 has been
satisfied


One qualification
procedure defined
Level 1:
based on
ASME IX



Two levels of welding procedure tests are
specified in order to make ISO 15614-1
Annexes
Relationship with
the Pressure
Equipment
Directive (PED) in
Annex ZA
Relationship
with the

Pressure
Equipment
Directive

(PED) in
Annex ZA.
Level 2 only 
is permitted
for
compliance
with the PED.
Level 1 does not provide presumption of
conformity with the Essential Safety
Requirements of the PED.
ISO 15614:2017 has yet to be published in the
official journal of the EU as harmonised
standard to the PED.
In the absence of specific requirements, the
authors recommend to apply Level 2, when
compliance with the PED is required.
Destructive and non-destructive testing
ISO 15614-1:
2004+A2:2012
ISO 15614-1:2017
Reason for
change and main
consequences
Table 2 Examination and testing requirements
See Table 1

Test requirements for Level
2 in Table 2.
Test requirements in
previous and in the


These are essentially
identical to the previous
edition (notes have been
revised for clarity).
Note d - 'need not be lower
than the parent metal
current version of
ISO 15614 (Level2)
are more stringent
than Level 1.
specification' has been
deleted'.
Figure 5 Location of test specimens in butt joints in plate

The welding direction is
Location of test specimens in
Figure 5 (welding direction topbottom of page, see below).
now from the bottom to the
top of page, but the
specimen location is the
same. So, the location of
test specimen with regard

to the start and end of the
weld has changed (see
below).
Macro and hardness
test specimen is now
near the start of the
weld. This was
located near the end
of the weld in the
previous edition of
ISO 15614-1.
Due to the heat
building up during
welding, hardness
values may be higher
at the start of the
weld, compared to


Key
1. Discard 25mm
2. Welding Direction
3. Area for:
 1 tensile test specimen;
 bend test specimens.
4. Area for:
 impact and additional test
Key
1. Discard 25mm

2. Welding Direction
3. Area for:
 1 tensile test specimen;
 bend test specimens.
4. Area for:
 impact and additional test
specimens if required
5. Area for:
 1 tensile test specimen;
specimens if required
5. Area for:
 1 tensile test specimen;
the end of the weld,
for the same welding
parameters. This
effect has not been
quantified.
So, the start of the
weld represent a
‘worst case’ for
hardness (ie highest
hardness).
Procedure
qualifications to the
current ISO 15614-1
may result in higher
hardness values.
Close monitoring of
the heating cycle is
recommended
(preheat, heat input),
especially when
borderline hardness
values are expected.
bend test specimens.
6. Area for:
 1 macro test specimen;
 1 hardness test specimen.
NOTE: not to scale.

bend test specimens.
6. Area for:
 1 macro test specimen;
 1 hardness test specimen.
NOTE: not to scale.

Figure 6 Location of test specimens in butt joints in pipe
No welding direction shown.
So, specimen locations around
the pipe circumference are the
same, regardless of the
welding progression (verticalup or down)
Figure 6 split into two
diagrams for vertical-up
and vertical-down
progressions, with
specimens in different
locations around the pipe

Takes into account
the effects of welding
progression on the
properties of different
areas around the
weld.
circumference.

NOTE: for the verticalo
down progression (righthand side) the location of
area 5 (start of weld, macro
and hardness) in the
diagram for the verticaldown progression seems to
For example:
When welding in the
vertical-up position,
the worst case area
for hardness (lowest
heat input, highest
hardness), is
expected to be in the
indicate that the start of
weld should be at 3 o’clock o
position. Also, the location
6 o’clock position.
When welding in the
vertical-down
of area 1 (end of weld),
seems to indicate that the
weld ends at the 12 o’clock
position. It is the opinion of
the authors that this is an
error and that a Key

position, the worst
case area for
hardness, is expected
to be in the 3 o’clock
position.
Specimen shall be
specific for the verticaldown progression diagram
should be added.
extracted from
different locations,
depending on the
welding progression
Table 3 Permitted maximum hardness values


For material groups 4,5 (heat 
treated): Max 320 HV10
For material groups 4,5
(heat treated): Max 350
HV10.
New note c: for certain
materials in Groups 4,5,
higher values may be

accepted, if specified before
the welding procedure test.
Group 4 includes Low
vanadium alloyed CrMo-(Ni) steels with
Mo ≤ 0,7 % and V ≤
0,1 % (eg 0.5Mo
steel)
Group 5 Cr-Mo steels
free of vanadium with
C ≤ 0,35 % (eg
1.25Cr -0.5Mo,
2.25Cr-1Mo, grade

91)
The ISO committee
agreed that the
permitted hardness
levels for Groups 4,5
in the previous
edition of ISO 156141 were too stringent
and the consensus
was that Groups 4,5
(heat treated) may
have a higher
hardness level,
without significantly

increasing the risk of
hydrogen cracking.
Footnote c was added
because it was also
considered that, for
these materials,
higher levels may be
acceptable providing
the hardness limit
was specified before
the welding
procedure test. This
may be useful, for
example, when
Group 4 and 5
materials are used
for their mechanical
strength, rather than
their high
temperature
properties.
7.5 Acceptance levels
Table 4 added to clarify
requirements
See clause 7.5

Acceptance criteria
have been made
clearer
Ranges of qualification
ISO 15614-1:
ISO 156142004+A2:2012 1:2017
Reason for change and main
consequences
8.2 Manufacturer
Qualification valid
Technical and

The new wording clarifies that a company
for other
workshops under
the same technical
and quality control
quality control
not mentioned.
Qualification
valid “in
workshops or 
sites when the
can apply another company’s WPQR,
provided that the companies that qualified
the WPQR retains complete responsibility for
all welding
For example: Company A, who carried out
the procedure qualification, can pass the
manufacturer
who performed
the welding
procedure test 
retains
complete
responsibility for
all welding”
WPQR to Company B, provided that
Company A retains complete responsibility
for all welding
Company A would take a significant risk, as
it would be responsible for welding carried
out by a different company.
8.3.1 Parent material grouping


Refers to CR ISO
15608
Refers to ISO/TR
15608.

Where materials
are assigned to 
groups by
ISO/TR 20172,
ISO/TR 20173 or
ISO/TR 20174,
Rules to assign parent material grouping
made clearer
ISO/TR 20172, ISO/TR 20173 or ISO/TR
20174 are very useful documents to assign
groups to EN, American and Japanese
materials

those
assignments
shall be used.
Separate
qualifications
required for
materials not
covered by
standards above
Table 5 Range of qualification for steel groups and subgroups
Table 3 has very
few dissimilar
Table 5 is much
more
combinations
comprehensive
Table 5 is now easier to use, especially for
dissimilar metal welds
Table 5 Range of qualification for steel groups and subgroups
For Group 11
(mainly
ASTM/ASME
materials), note b
For Group 11, 
note a applies,
ie equal or lower
specified
Group 11 covers ASTM/ASME carbon steels,
for which the specified maximum carbon
content (up to 0.30%) is typically greater
than for ‘EN or ISO steels’
applies, ie steels in
the same subgroup and any
minimum yield 
strength steels
(independent of
Group 11 steels represent a worse case in
terms of weldability (potentially higher
carbon), compared to EN or ISO steels with
lower sub-group
within the same
group lower subgroups are
qualified
the material
thickness) are
qualified


the same or lower specified yield strength
The previous standard was considered
unnecessarily restrictive, as Group 11
materials only qualified Group 11
Group 11 material now cover Group 1 with
the same or lower specified minimum yield
strength
Table 6 Range of qualification for nickel alloys groups and subgroups

Table 6 is much
more
comprehensive
Table 4 has very 
few dissimilar
combinations
Dissimilar
combinations for
groups 8-4X and
11-4X
introduced
Table 6 is now easier to use, especially for
dissimilar metal welds
Table 7 Material and weld deposit thickness (butt welds)
Table 5 has the
same ranges for

Separate
qualification

Weld metal thickness and material thickness
are treated separately to improve clarity
weld deposit
thickness material
thickness
ranges for levels
1 and 2
Table 7
essentially
similar to


o
o
previous Table
5, except:
Deposited weld
metal thickness
(s) and material
thickness (t)
treated
separately
Ranges for
thickness of test
piece have
changed
No minimum
thickness for
deposit
thickness
0.5t – 2t for
material
Users should be aware of the new thickness
of test piece ranges and the new
qualification ranges.
o
o
o
thickness < 3
When s(test) >
20, new rules for
s(max)
t(test) ranges
20-40, 40-100,
100-150,
>150mm
S(max) =
1.33s(test) if t ≥
150
Table 8 Material and throat thickness for fillet welds


Table 6:
3<t<30mm range
= 0.5t(3 min) – 2t
t ≥ 30 : single run
throat – no range 
(each throat depth
to be qualified
separately)

Table 8 :
3<t<30mm

range = 3-2t
Single run throat
– range is 0.75a
– 1.5a
As 3mm is the minimum material thickness
then changed from 0.5t(3 min) – 2t to 3-2t
The standard committee considered that
there should be a range of qualification for
the throat thickness and not restricted, as
previously, to the throat thickness used in
the test piece.
Table 9 Pipe and branch connections diameter


Table 7 :
For D ≤ 25 range
is 0.5D – 2D
For D > 25 range
is ≥ 0.5D (25 min)

Range is ≥ 0.5D
for all diameters
The committee considered the previous
ranges to be too restrictive, so a range of ≥
0.5D for all diameters was agreed.
8.4.1 Welding processes

For multi-run
o
welds, no
requirement to test
weld metal
deposited from
each welding
process
o
When the test
piece is welded
with more than
one welding

process;
The procedure is
valid only for the
sequence of
processes used
on the test
piece.

Test specimens
shall include
deposited
material from
each welding
process used.
For multi-process welds, the test specimen
must now include deposited metal from each
welding process. This was not explicitly
required in the previous edition.
For multi-process qualification (eg
TIG+MMA), either of the processes can be
used to deposit a backing run

Addition: “back
run is permitted
using one of the
welding
processes used
in the
qualification.”
8.4.2 Welding positions

8.4.2

The wording has
been revised,
the principles
There has been much discussion on the
clause and the wording was revised to make
it clearer. The principles are largely the same
are the same
apart from;

two test pieces
are required
except in the
case of when a
fixed pipe is

used for the
but;
In case of fixed pipe, it is not necessary to
weld two test pieces since, for example, the
hardness can be taken from the overhead
position (PE) and the impact from the
horizontal (PC) position - see Fig 6
The UK specifically asked for the following to
be included 'Vertical down welding (welding
qualification.
More examples
of high and low
positions PG, PJ and J-L045) shall be
qualified by a specific test' which was
agreed.
heat input
positions
provided in a
NOTE



The Note was added to help the user to
understand which are the highest and lowest
heat input positions.
The use of ‘and’ in the note, for example ‘PF
and PA’ for high heat input position, may be
misleading. Users may believe that two test
pieces, one in PA and one in PF position, are
required to test the high heat input. The
intent of this note is that only one position
per heat input level is required.
IMPORTANT: notes are included in standards
to give examples and help the users. A note
cannot include requirements. The positions
specified in the note are for example only.
The user may apply positions other than
those indicated in the note.
8.4.3 Type of weld / joint

8.4.3
New clauses: 
Weld made from
(i) and (k) were agreed by the committee
and cover conditions that were not explicitly
both sides
qualifies welds 
made from one
addressed in the previous edition
(j): a change from single to multi-run, and
vice-versa, is expected to affect hardness



side with
backing
Build-up
qualified by butt
weld
Buttering shall
and toughness in the HAZ and weld metal. If
hardness and toughness are not to be
tested, this change should not apply.
(h) is not permitted when thermal gouging
(arc air, plasma) is used to remove the weld
root, because this is a thermal process and it
be performed by
a separate test
piece in
combination with
the butt weld (to
allow mechanical
testing).
Modified clause
affects the mechanical properties of the
joint.
(new text in
Italic):
When impact or
hardness
requirements
apply, it is not
permitted to
change a multirun deposit into
a single run
deposit (or
single run on
each side) or
vice versa for a
given process
8.4.4 Filler materials

Covered by
separate clauses 
8.4.4 (designation)
and 8.4.5 (make)
Covered by one
clause (8.4.4)
Process 137 is
replaced by
process 132

8.4.5: filler metals
restricted to the
specific make for
‘fluxed’ processes
111 (MMA), 114
(self-shielded), 12
(SAW), 136 (FCAW
inter gas) and 132
Restrictions on 
filler metals for
‘fluxed’

processes
(manual metal
arc, SAW,
FCAW) if impact
testing is
(FCAW active gas)
required at
temperatures
less than -20°C

Process 137 has been replaced by process
132 in the latest version of ISO 4063
The requirement for testing at -20°C is only
mandatory if required by the Application
Standard
8.4.7 Heat input (arc energy)




8.4.8:
heat input only to
be recorded
±25% qualified

range, depending
on testing
requirements
Heat input
calculation
according to EN
1011-1

8.4.7:

User can use
either heat input
or arc energy for
welding control,
Reference to ISO/TR 18491 to take modern
power sources into account
The traditional formula for heat input/arc
energy in EN 1011-1 is inadequate when
pulsed welding (eg P-GTAW or p-GMAW) or
to be calculated
in accordance
with ISO/TR
18491

the calculation
(either heat
input or arc
power sources with complex waveforms are
used (eg Lincoln STT, Fronius CMT, ESAB
Superpulse, Kemppi WISEROOT etc)
Using the traditional formula and average
values for A and V has been proven to be
inaccurate. Also, average A and V cannot be
readily determined, when a complex
energy) shall be
documented

±25% qualified
range stays the
same (+25% 
when there
impact
waveform is applied.
ISO/TR User can report heat input or arc
energy, to be calculated according to
ISO/TR 18491
provides separate rules to calculate heat
input/arc energy for waveform controlled
and non-waveform controlled processes
requirements 
apply and -25%
when hardness 
These are identical to the rules introduced in
ASME IX since 2010
User should familiarise with ISO/TR 18491

requirements
apply)
For tack welding
heat input need
not be verified
but adjustable
parameters
(amps/volts)
should be
checked
8.4.8 Preheat temperature

8.4.9:
The minimum
qualified preheat
temperature is that
recorded in the
test (applied at the
start of the test)
The preheat

Preheat temperature reduction similar to
temperature can
be reduced by 
no more than
50°C from the
recorded

preheat
temperature on
the WPQR
ASME IX, which permits a 55°C reduction .
A reduction of 50°C is permitted, rather than
55°C, to prevent level from being less
stringent than ASME IX
It is permissible to reduce the preheat
temperature from the recorded preheat
temperature on the WPQR but by no more
than 50°C and only if ISO/TR 17671-2 is
otherwise
requalification is
required
satisfied
This does not mean that preheat should be
reduced for production welding. ISO/TR

A decrease in
the preheat
temperature is
only permitted if
ISO/TR 17671-1
2 is satisfied
17671-2 should be applied to determine the
required level of preheat for production
welding.
Also, a decrease in preheat temperature may
not be permitted by the applicable
construction code, if any.
8.4.9 Interpass temperature

8.4.10:
Upper limit for the
interpass

temperature (IP) is
that recorded in
test.
An increase in
the maximum
interpass

temperature of
more than 50°C 
IP temperature increase similar to ASME IX,
which permits a 55°C increase .
An increase of 50°C is permitted, rather than
shall require requalification
For Groups 8, 
10, 41-48, there
is no change, as
the maximum
interpass
temperature (IP)
55°C, to prevent level 2 from being less
stringent than ASME IX
Increase not permitted for austenitic
materials (groups 8, 41-48) and duplex
stainless steels (group 10), as this may
adversely affect properties such as
toughness, phase balance and corrosion
resistance
is that recorded
in the welding
procedure test.
8.4.11 Heat treatment

8.4.12:

PWHT temperature
range validated is
the holding
temperature
recorded in the
test ± 20°C

No changes from
previous
standard
regarding
temperature
range validated
and heating
rates etc.
Introduction of 
four PWHT
conditions which
will require a
separate
procedure
qualification
For material
groups 1-7, 9-11
the following
conditions apply:
- Stress relief
(below lower
transformation
Introduction of four groups of PWHT in line
with ASME IX (see QW-407.1)
Major change is the introduction of four
types of PWHT for ISO/TR 15608 material
groups 1-7, 9-11
temperature),
- normalizing
(above upper
transformation
temperature),
- normalising


followed by
Q&T,
- PWHT between
lower and upper
transformation
temperatures.
PWHT
temperature
range validated
is still the
holding
temperature
recorded in the
test ± 20°C
For all other
groups PWHT
shall be ‘within a
specified
temperature
range’.
8.5.1 Submerged arc welding


8.5.1:
8.5.1.1 Each
process variant
shall be qualified
independently

8.5.1.2 Range is
limited to ‘make
and designation’ of
the flux

8.5.1(a) Each
process 12
variant (121 to
126) shall be

qualified
independently.
The introduction
of process

variant such as
multi-wire,

addition of hot
or cold wire, etc
will require

requalification
8.5.1(b) Range
is limited to the
‘manufacturer,
trade name and
designation of
the flux’
Clause revised to improve clarity and
address some frequently asked questions
from users (eg on multi-wire, hot/cold wire
etc)
Clause on re-crushed slag added in line with
ASME IX (QW-404.36)
Limiting the range of qualification to the
Trade Name used in the test is an additional
restriction.
It should be noted, when using re-crushed
slag a new batch or blend of crushed slag
requires a new qualification test.

8.5.1(c) New
clause added to
cover the use of
re-crushed slag
8.5.2.1 Gas-shielded metal arc welding (Shielding gases)


8.5.2:
Increase of 10% of
CO2 content
permitted for
shielding gas
Maximum
permissible
deviation for the
o
CO2 content has
now been
clarified as a
‘relative
deviation’ of
±20% of CO2
from nominal
composition
o

o
o
The previous wording (shall not exceed
10%) was unclear and numerous enquiries
were being submitted
For example, if an increase of 10% is
permitted, does a gas mixture 80% Ar 20%
CO2 cover:
Up to 22% CO2, calculated as [20 + (10% of
20)]
or
Up to 30% CO2, calculated as (20%+10%)
According to ISO 15614-1:2017, for the
example above, ‘relative deviation of ±20%’
means that a gas mixture 80% Ar 20% CO2
covers:
Minimum 16% CO2, calculated as [20 (20% of 20)]
Maximum 24% CO2, calculated as [20 +
(20% of 20)]
8.5.2.3 Gas-shielded metal arc welding (Transfer mode)

Spray or globular
transfer modes
qualify spray and
globular
New clause on
Transfer Mode
8.5.2.3.1 The
range of
qualification for
the various
transfer modes
including the
pulsed mode eg
qualification
using spray,
pulsed or
Range of qualification now covers the pulsed
transfer mode and the newer waveformcontrolled power sources
globular qualifies
spray, pulsed
and globular
No reference to
waveform
controlled welding 
New clauses on
waveform

controlled
welding:
In practice:
If a power source with a complex waveform
is used (eg Lincoln STT, Fronius CMT, ESAB
Superpulse, Kemppi WISEROOT, EWM
8.5.2.3.2
Waveformcontrolled
forceArc etc), the power source
manufacturer and the waveform mode must
be recorded in the WPQR and cannot be

welding: the
power source
manufacturer 
and waveform
control mode are
essential
changed. For example, a qualification with
Lincoln STT only covers Lincoln STT.
If ‘conventional’ pulsed welding is applied
(no complex waveform), the power source
manufacturer and the pulse parameters
must be recorded in the WPQR. The power
variables
8.5.2.3.2
Welding with
pulsed mode
and without
waveformcontrol: the
power source
source manufacturer can be changed without
requalification. NOTE: all other variables
must be within the qualified range. So, one
can change the power source BUT the
pulsing parameters must be such that the
qualified heat input limits are not exceeded.
For ‘standard’ welding (no complex
waveform or pulsing): the power source

manufacturer
and other
pertinent
information shall
be recorded, but
a change does
not require

requalification
8.5.2.3.2 Non
waveform-
manufacturer shall be recorded in the WPQR,
but it can be changed without requalification.
control welding:
the power
source
manufacturer
shall be
recorded, but a
change does not
require
requalification
8.5.3.1 TIG welding, shielding gases

8.5.3:
Shielding gas
mixture limited to
symbol of the gas 
or nominal
composition
Shielding gas
mixture limited
to the nominal
composition or
symbol of the
gas.
A relative
deviation of
max ±10% from
the nominal He
content is
permitted
See 8.5.2.1 for explanation of ‘relative
deviation’
8.5.4 Plasma arc welding
A change in the
type of joint
preparation
(groove)
requires a re-
8.5.4:
No reference to
joint type
Clause on joint type added in line with ASME
IX (QW-257 and QW-402.1)
qualification.
8.5.6 Backing gas, all processes


8.5.3:
Backing gas rules
apply to process

14 only
8.5.3.2 A weld
procedure test

made without a
backing gas
qualifies a welding
procedure with
backing gas.

New clause on
Backing Gases
which covers the
Material Groups
Backing gas
rules apply to all
processes
No backing gas
qualifies backing
with I and N1N3 to ISO 14175
(not vice versa)
Main group to
ISO 14175
The rules on backing gas have been
improved following feedback from users




covers all subgroups within
the same group
Material groups
1-6 – Gas
groups I and N1,
N2, N3 are
interchangeable
Material groups
7 and 10 – Any
change in
backing gas
classification
requires
requalification
Material groups
8, 41-48 – Gas
groups I, N, R
are
interchangeable
Backing gas can
be omitted when
≥5mm thick
material backing
is used
Annex A
Not present
New Annex but
not relevant for
Level 2
Authors
Andy Brightmore (TWI) – Software Business Development ( http://www.twisoftware.com/ ).
Marcello Consonni (TWI) - Member of ISO subcommittee ISO /TC 44/SC 10 ‘Quality management in the field of welding‘, UK national committee WEE/36
‘Qualification of welding personnel and welding procedures’ and contributing member of ASME BPVC Section IX committee.
Professor Bill Lucas – UK delegate on ISO subcommittee ISO /TC 44/SC 10 ‘Quality management in the field of welding‘, national committee WEE/36
‘Qualification of welding personnel and welding procedures’.
Last reviewed: September 2017