EN 13480-5:2002 (E) Issue 1 (2002-05)
start
random testing
welds acceptable ?
yes
no
test 2 additional welds
yes
additional welds acce table ?
no
test all welds of that group
repair tested welds with unacceptable imperfections and re-examine
welds acceptable ?
yes end
no
Figure 8.1-1 — Flow diagram of additional testing required when imperfections have been revealed
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EN 13480-5:2002 (E) Issue 6 (2006-03)
8.2 Circumferential Circumferential butt, branch, fillet and seal welds 8.2.1
Amount of examination
The type of NDT required and its extent shall be determined in accordance with Table 8.2-1, taking into account the piping category the piping is classified to. The following additional conditions shall apply: a)
For piping where creep or fatigue is the controlling factor in design, it shall be assigned to piping category III for determining the extent of NDT, irrespective of PS and and DN;
b)
For piping in material groups 1.1, 1.2, and 8.1, in piping classes I or II, volumetric testing testing shall be a minimum of 10 % of circumferential butt and branch welds irrespective of PS and DN, if the piping is > DN 25 and contains very toxic or extremely flammable fluids;
c)
Where the specified NDT level is 5 %, this shall apply to the first 100 welds made. Where no unacceptable imperfections are identified in this sample, the level of testing may be reduced to an overall level of 2 %. However, the minimum number of welds examined shall be 5. All other requirements given in 8.1.2 shall apply;
d)
For the circumferential welds where the calculated stresses across the weld (as determined using using EN 13480-3) are below 70 % of the nominal design stress for the design conditions, the amount of testing may be reduced by 50 % of the values given in Table 8.2-1;
e)
Piping for steam and superheated water (water at a pressure greater than 0,5 bar and at a temperature equal to or greater than 110 °C) shall be subject to the following NDT:
where
PS
where
PS · ·
· DN ≥ 5 000, 100 % volumetric testing of butt and branch welds; DN ≥ 3 500, 25 % volumetric testing of butt and branch welds;
together with other testing specified in Table 8.2-1 for the combination of m aterial, piping category and thickness; NOTE For piping operating at 100 °C or more, at least 10 % of socket welds should be radiographed to confirm that an adequate expansion gap has been achieved.
f)
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For the selection of the appropriate NDT NDT method for volumetric testing, see Table 8.4-4. 8.4-4.
EN 13480-5:2002 (E) Issue 6 (2006-03)
Table 8.2-1 — Extent of testing for circumferential, branch, fillet and seal welds Material group a
Piping Class
All welds
Circumferential welds Surface testing
VT %
en
b
mm
MT/PT c %
II
100
3.1, 3.2, 3.3 5.1, 5.2, 5.3 5.4, 6.1, 6.2, 6.3, 6.4, 7.1, 7.2, 11
II
100
III I II
n
100
III
≤ 30 > 30 ≤ 30 > 30 ≤ 30 > 30 ≤ 30 > 30 ≤ 30 > 30 ≤ 30 > 30
5 10 5 10 5 10 10 25 25 25 100 100
10 10 10 10 25 25 d 25 25 25 25 d 100 100 d
All e
Material group, see CR ISO 15608. For the selection of the appropriate NDT-method NDT-method for volumetric testing, see see Table Table 8.4-4. 8.4-4. For ferritic materials preference shall be given to MT. Additional testing for transverse defects from weld surface (see 8.4.4.2).
e
Only if PWHT has been carried out.
RT/UT %
en
mm
MT/PT %
en
mm
MT/PT %
All
Nil
All
Nil All
10
b c
b
All
a
d
en
mm
Nil Nil
10
I
Socket/fillet Socket/fillet Seal welds welds Surface Surface testing testing Surface Surface testing testing
Volumet Volumetric ric testing testing
e Branch MT/PT c Branch diameter mm % diameter
5
III 1.3, 1.4 2.1, 2.2 4.1, 4.2 8.2, 8.3 9.1, 9.2, 9.3 10.1, 10.2
Surface testing testing
5
I 1.1 1.2 8.1
Volumetric testing RT/UT %
Branch welds
> DN 100
> 15
All
10
10
10
Nil
All e
10
All e
5
10
All All
25
All All
25
10 > DN 100 100
All 25 All
> 15
25 All
100
25 All
100
10 All
100
100
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EN 13480-5:2002 (E) Issue 1 (2002-05)
8.2.2
Dissimilar metal joints
The test methods and extent of testing for joints between ferritic and other materials (e.g. austenitic, nickel-based alloys) shall be according to the highest material group which is applicable to the base materials.
8.3 Longitudinal welds Longitudinal welds, except those in components made to material specifications acceptable to this European Standard, shall be subject to the level of NDT appropriate to the joint coefficient required (see Table 8.3-1). Table 8.3-1 — Extent of NDT for longitudinal welds Joint coefficient
VT
MT or PT
a
RT or UT
b
Z
%
%
%
z ≤ 0,7
100
0
0
0,7 < z ≤ 0,85
100
10
10
0,85 < z ≤ 1,0
100
100
100
a for ferritic materials preference preference shall be given to MT. b see Table 8.4-3
8.4 NDT Methods 8.4.1
General
The NDT methods specified in the following clauses shall be performed in accordance with written NDT procedures, and, where appropriate, with NDT instructions. 8.4.2
Acceptance criteria
The acceptance criteria for the NDT techniques shall follow the European Standards in Table 8.4-1. Requirements for acceptance criteria for surface imperfections are given in Table 8.4-2 and additional requirements for acceptance criteria for internal imperfections detected by RT are given in Table 8.4-3. Table 8.4-1 — NDT techniques, method, acceptance criteria NDT Technique (abbreviation) Visual Examination (VT) Radiographic Testing (RT)
Method
Ultrasonic Testing (UT)
EN 1714:1998, class B
Penetrant Testing (PT)
EN 571-1
Magnetic Particle Testing (MT)
EN 1290
EN 970 EN 1435:1997, class B
Acceptance Criteria
ab
b
Table 8.4-2 EN 12517:1998 Acceptance level 2 and additional requirements of Table 8.4-3 EN 1712 :1997, c Acceptance level 2 d EN 1289 :1998, Acceptance level 1 EN 1291 :1998, Acceptance level 1
a However, the maximum area for single exposure shall correspond to the requirements of EN 1435:1997, class A. b Class A for material group group 1.1, 1.2, 8.1 when piping class is I or II. c For the characterization of indications EN 1713 may be used. d Acceptance level 3 for material material group 1.1, 1.2, 8.1 when piping class class is I or II.
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