Download - EN 288-3x
pWPS
WPAR
WAR
WPS
PRODUCTION
Preliminary
Approval of welding procedure
Welders approval
Welding Procedure Specification
Welding Procedure Specification
Required ApprovalsAvailable? Yes
Approved consumables
Experience
Standard procedure
Pre-production tests
TestweldingTesting
Reporting
pWPS
WPAR
WAR
WPS
PRODUCTION
Preliminary
Approval of welding procedure
Welders approval
Welding Procedure Specification
Welding Procedure Specification
Required ApprovalsAvailable? Yes
Approved consumables
Experience
Standard procedure
Pre-production tests
TestweldingTesting
Reporting
P. Loos 99
A weld cannot be checked to the full extent!
strength, ductility and corrosion resistance can only be checked by destructive techniques.
properties can only be guaranteed for the
actual product when manufactured to
exactly the same written procedure,
and carefully controlled.
EN 288
Why a WPSWhy a WPS
P. Loos 99 EN 288-3
Why a WPSWhy a WPS
The main objective of a WPS is to make awelding operation
reproducable
P. Loos 99 EN 288
Methods of approvalMethods of approval
welding procedure tests - EN 288 part 3 or 4
approved welding consumables - EN 288 part 5
previous welding experience - EN 288 part 6
standard welding procedure - EN 288 part 7
pre-production welding tests - EN 288 part 8
P. Loos 99 EN 288-3
Acceptance criteriaAcceptance criteria
EN 25817 level “B”
EN 25817 level “C” excess throat thickness
excess convexity excess weld metal
excessive penetration
P. Loos 99 EN 288-3
Acceptance criteriaAcceptance criteria
Strength according to parent metal
Impact requirements (temperature, energy)
according to the design requirements (and application standard)
P. Loos 99
EN 288 - ISO 9956EN 288 - ISO 9956Specification and approval of welding
procedures for metallic materials
Part 1 General rules for fusion welding
Part 2 Welding procedure specification for arc welding
Part 3 Welding proc. tests for the arc welding of steels Part 4 Welding proc. tests for the arc welding of aluminium and its alloys Part 5 Approval by using approved welding consumables for arc welding
Part 6 Approval related to previous experience
Part 7 Appr. by a stardard welding proc. for arc welding
Part 8 Approval by pre-production welding test
P. Loos 99 EN 288-3
Additional testsAdditional tests
Such tests may include:
longitudinal weld tensile test all weld metal bend test Charpy V-notch impact test yield strength or 0,2 % proof stress elongation chemical analysis micro examination delta ferrite determination in austenitic stainless steels
P. Loos 99 EN 288
Material groupsMaterial groups
The use of particular method of approval of a WPS is often a mandatory require-ment of an application standard.
In the absence of such a requirement the method of approval shall be agreed bet-ween the contracting parties at the enquiry or at the order stage.
P. Loos 5/99 EN 288
Approval of WPSApproval of WPS
Preliminary welding procedurespecification
( pWPS )
Approval on the pWPS by a methodacc. to EN 288 part 3/4, 5, 6, 7 or 8
Approved welding procedurespecification
( WPS )
P. Loos 99 EN 288-3
Welding Welding procedure tests tests
Tests shall be carried out in accordance
with this standard unless more severe
tests are specified by the relevant
application standard or contract
when these shall apply.
P. Loos 5/99 EN 288-3
Welding procedure testsWelding procedure tests
All new
welding procedure approvals
are to be in accordance with this
standard from the date of its issue
(first issue april 1992)
P. Loos 5/99 EN 288-3
Welders approval
The welder who undertakes the
welding procedure test satisfactory,
is approved for the appropriate
range of approval given in the
relevant part of EN 287
P. Loos 5/99 EN 288-3
Re - testing
If the test piece fails to comply with any of the requirements for visual examinaton or NDE, one further test piece shall be welded and subjected to the same examination. If this additional test piece does not comply with the relevant requirements, the pWPS shall be regarded as not capable of complying with the requirements of this standard without modification.
P. Loos 5/99 EN 288-3
Re - testing
If any test specimen fails to comply with the relevant requirements only due to geometric weld imperfections, two further test speci-mens shall be obtained for each one that failed.
These can be taken from the same test piece if there is sufficient material available or from a news test piece, and shall be subjected to thesame test.
P. Loos 5/99 EN 288-3
Re - testing
If either of these additional test specimens
does not comply with the relevant require-
ments, the pWPS shall be regarded as
not capable of complying with the require-
ments of this standard without modification.
P. Loos 5/99 EN 288-3
Range of approval
An approval of a WPS obtained by a
manufacturer is valid for welding in
workshops or sites under the same
technical and quality control of
that manufacturer.
P. Loos 99 EN 288-5
Essential variables
Process: 111; 114; 131; 135; 136; 137; 141
Material: group 1, 9 (EN 288-3)
group 21, 22a, 22b (EN 288-4)
Parent metal thickness: 3 - 40 mm
Size of fillet weld: 3 mm
Pipe diameter: > 25 mm
P. Loos 99 EN 288-5
Approved welding consumables
Some material do not deteriorate significantlyin the heat affected zones, provided heatinputs are kept within specified limits.
For such materials, a pWPS shall be con-sidered approved on the condition that thewelding consumables are approved and thatall essential variables are within the rangefor which the approval is valid
P. Loos 99 EN 288-6
Previous experience
A manufacturer may have a pWPS appro-
ved by referring to previous experience on
condition that he can prove by appropi-
ate documentation of an independant
nature that he has previously satisfactorily
welded the type of joint and materials in
question
P. Loos 99 EN 288-6
Previous experiencePrevious experience shall involve:
Satisfactory documentation of tests (e.g. non- destructive, destructive, leak or pressure tests) in all cases.
AND A summary of welding manufacturing of at least one year during an appropriate period (5 years)
ORSuitability of welds in service for an appropri-
ate period (5 years)
P. Loos 99 EN 288-7
Standard welding procedure
A standard welding procedure shall beissued as a specification in the format ofa WPS or WPAR based on an approvalto the relevant part of EN 288 for weldingprocedure testing.
Application of a standard welding proce-dure is also subject to be satisfied bythe user.
P. Loos 99 EN 288-7
Essential variables
Process: 111; 114; 131; 135; 136; 137; 141
Material: group 1, 9 (EN 288-3)
group 21, 22a, 22b (EN 288-4)
Parent metal thickness: 3 - 40 mm
Size of fillet weld: 3 mm
Pipe diameter: > 25 mm
P. Loos 99 EN 288-7
Standard welding procedure
The use of a standard weldingprocedure requires welding coordi-nation in accordance with EN 719.
The user has to fullfill quality requi-rements in accordance with the ap-propriate part of EN 729.
P. Loos 99 EN 288-8
Pre - production welding tests
At least the following tests are to be performed:
a) visual inspection (100 %)
b) surface crack detection
c) hardness tests (for Re 275 N/mm²)
d) macrographic examination
P. Loos 99 EN 288-8
Pre - production welding tests
Pre-production welding test are used where theshape and dimension of standardized test pie-ces do not adequately represent the joint to bewelded.
One or more special test pieces shall be madeto simulate the production joint in all essentialfeatures e.g. dimensions, restraint, heat sinkeffects.
P. Loos 99 EN 288-2
Content of a WPs
preparation of the components to be welded
assembling of components for welding
welding process
post work of the welded connections(e.g.grinding)
heat treatment (during fabrication/finalizing)
P. Loos 99 EN 288-3
Material groups
a procedure test with one steel of a group co-vers the lower alloyed steels of the samegroup or the steels with equal or lower speci-fied yield strength of this groupas long as the welding consumables used forthe test can also be used for the steels of thisgroup
group 2 covers group 1
P. Loos 99 EN 288-3
WPAR
Welding Procedure Approval Record
(WPAR)
The welding procedure approval record WPAR)is a statement of results of assessing each testpiece including re-tests.It shall be signed by the examiner or test body
P. Loos 99 AD HP 2/1
Pressure vesselThe welding procedure tests for pressure vesselsare detailed in the AD-Merkblatt HP 2/1.
Welding and testing must be witnessed by theauthorised Inspector.
The results of the procedure qualification testingshall be available prior to the production.
The qualification is based on
EN 288-3 EN 288-4
P. Loos 99 AD HP 2/1
Pressure vessel
Additional requirements are given for:
material groups
welding positions
amount of testing
approval requirements for testing
P. Loos 99 AD HP 5/2
Production testsThe number of the test pieces and the type of de-structive and non-destructive testing depends on:
type of joint (round seam, long seam)
design stress level of the welded joint
(85 %, 100 %)
the base material
number of shell rings
post heat treatment (U, W)
thickness of base material
P. Loos 99 EN 288
SummaryQ u a l i t ä t s k o n t r o l l e w ä h r e n d d e rF e r t i g u n g I u n d I I
S F I - 3 / 4 . 4 - 4 . 5S e i t e 1
W h i c h p o s s i b i l i t i e s o f a p p r o v a l o f w e l d i n g p r o c e d u r e s a r e a v a i l a b l e ?
W h a t a r e t h e l i m i t s o f t h e s e p o s s i b i l i t i e s ?
W h i c h i m p o r t a n t e s s e n t i a l v a r i a b l e s a r e i n c l u d e d i n t h e W P S ?
W h a t t y p e o f t e s t p i e c e s a r e s t a n d a r d t y p e s a c c o r d i n g t o E N 2 8 8 - 3 ?
W h i c h t e s t s ( n o n d e s t r u c t i v e o r d e s t r u c t i v e ) a r e n e c e s s a r y f o r E N 2 8 8 - 3 ?
P. Loos 99 EN 288
SummaryQ u a l i t ä t s k o n t r o l l e w ä h r e n d d e rF e r t i g u n g I u n d I I
S F I - 3 / 4 . 4 - 4 . 5S e i t e 1
W h a t a r e t h e a c c e p t a n c e c r i t e r i a f o r t h e w e l d e d j o i n t o f t h e p r o d u c t i o n t e s t ?
W h a t e a s e g i v e s t h e g r o u p i n g s y s t e m f o rs t e e l a c c o r d i n g t o E N 2 8 8 - 3 ?
W h a t a r e t h e r a n g e s o f a p p r o v a l f o r t h i c k -n e s s a n d d i a m e t e r ?
W h i c h c h a n g e s t o E N 2 8 8 - 3 a r e m a d e i n t h e G e r m a n s t a n d a r d s a n d r e g u l a t i o n s ?
W h a t i s t h e s e n s e o f a p r o d u c t i o n t e s t ?
P. Loos 99
Production tests
The requirements ofproduction tests in the field of
steel structuresare given in guideline
DVS 1702.
For aluminium and aluminiumalloys the DIBt guideline is
applicable
P. Loos 99
Steel structuresBased on the requirements of DIN 18 800 Teil 7,welding procedure tests for steel structures arerequired if:
a) fully mechanized processes are used
b) fine grain steels with a yield strenght (Re) > 360 N/mm2 are used
Welding and testing has to be performed under thewitness of a representative of the accredeted inspec-tion authoraty for the comprehensive form of verifica-tion.
P. Loos 99
Steel structuresFor the fully mechanized processes and for
fine grain steels with (Re) > 360 N/mm2 ,the
requirements of EN 288-3 are applicable.
Exceptions:
Fillet welds are not covered by butt welds.
Welding and testing of fillet welds has to be do-ne in accordance with Guideline DVS 1702(cruziform test).
P. Loos 99
Aluminium structures
Welding procedure tests for aluminiumstructures must be performed in accor-dance with the guideline of the GermanInstitute of Structural Engineering (DIBt)
For butt welds the guideline is based onEN 288-4