Welding Fabrication Standards - EWF

Welding Fabrication Standards Page 78
8.3.2 Requirements for inspection and testing and acceptance criteria
Inspection and testing follow the general rules reported in EN ISO 3834; moreover different criteria
are considered for extension and timing, depending on the following parameters:
- place of execution (Worksop pre-fabrication – on site production);
- type of weld (transverse welds, longitudinal welds, strength welds, attachment welds);
- joint utilisation factor - k (defined as k = σ / σe, relationship “ULS stress / yield stress” in the
weld);
- execution class (E.C., already previously defined).
Visual inspection has to be performed for the overall length of the welds, independently from the
above cited factors; moreover for execution classes 1 to 3 additional testing is required, according
to the following table.
It has to be noted that there is not any specific guidance on the testing method, as general criteria
reported in EN 12062 for the field of application of NDT testing apply.
Requirements, depending on the
joint type
Independently from the joint type,
general extension for NDT activities
Transverse butt
welds subjected to
tensile stress
Transverse butt welds subjected to
compression stress
Transverse fillet welds at end of lap
joints and at connection gussets.
Longitudinal welds and welds to
stiffeners.
Attachment welds (e.g. for fixing
purlins, side rails, etc.)
Execution Class -
Workshop
Execution Class – On site
1 and 2 3 1 and 2 3
The first 5 joints of each
same type* shall be
tested according to the
following values.
All joints shall
be tested
according to the
following values
The first 5 joints of each
same type* shall be tested
according to following
values. The extent of
additional NDT is reduced to
50 % (minimum of 10%)
0.8 ≤ k 100 % 50 % 100 % 100 %
0.3 < k< 0.8 50% 20% 100% 50%
k ≤ 0.3 10% 5% 20% 10%
10 % 5 % 20 % 10 %
20 % 10 % 20 % 10 %
10 %, 5 % 20 % 10 %
* Same basic dimensions, material grades, weld geometry and welded to the same procedures.
Table 20 – Additional Requirements for NDT extension for Execution Classes 1 to 3.
Unless otherwise specified, the acceptance criteria for welds shall be as follows, with reference to
EN ISO 5817: Any special requirements on weld geometry and profile shall be taken into account.
Execution class Acceptance criteria
4 EN ISO 5817 – Quality level D
3 EN ISO 5817 – Quality level C
2 EN ISO 5817 – Quality level B
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