Control of welding quality

D.1.2.1 Quality requirements

(1) The manufacturer shall conform with the quality requirements of EN 729-2. D.1.2.2 Welding co-ordination

(1) The welding co-ordination personnel shall have comprehensive technical knowledge in accordance with EN 719.

D.1.2.3 Welding procedures

(1) Welding procedures shall be approved in accordance with EN 288-4. D.1.2.4 Welder approval

(1) Welders shall be approved in accordance with EN 287-2. D.1.2.5 Welding processes

(1) Control of welding shall be in accordance with EN 1011-1 and 4. D.1.3 Methods and extent of Inspection

(1) The methods and minimum extent of inspection shall be in accordance with Table D.1 for the purposes of final inspection of the work, unless otherwise agreed with the purchaser.

Table D. 1. Methods and extent of inspection for production welds

Inspection stages

Features requiring inspection

Joint type

Orientation4)

Weld type

Required quality level

Number of joints of each type l) 3)

%

Stage 1. Immediately prior to welding

Visual and dimensional inspection

surface condition, preparation and fit-up dimensions, jigging and tacking requirements

All

All

All

All

100

Stage 2. After completion of welding2)

Visual and dimensional inspection

overall weld geometry, profile discontinuities, surface discontinuities

All

All

All

All

100

Stage 3. After visual inspection)

Non-destructive testing

(a) surface discontinuities

(b) sub-surface discontinuities

Penetrant dye

Ultrasonic

Radiographic

8mm<t <25mm

t>25mm

t<8mm

t>8mm

Butt

Trans

Double sided butt

Fat 25 Fat 3i Fat 39 Fat 49

100S/S

100 100 100 100

100 100 100 100

5 DF 20 100 100

100

Single sided butt

unbacked backed

Normal Fat 25

100S/S 100

1005) 100

100 100

5 DF

-

Cruciform

Trans

Butt

Normal Fat 25 Fat 31

100S/S 100 100

-

20 100 100

-

-

Cruciform

Trans

Fillet

Normal Fat 25 Fat 31

100S/S 20 100

-

-

-

-

*

Lap

Trans

Fillet

Normal

100

All

Longl

All

Normal Fat 25 Fat 31 Fat 39 Fat 49 Fat 62

100 WE 100 WE 100 S/S 100 S/S 100 100

-

-

5

continued/

Table D.l. Methods and extent of inspection for production welds (continued)

Inspection stages

Features requiring inspection

Joint type

Orientation 4)

Weld type

Required quality level

Number of joints of each type 1)3) %

Stage 4. After non-destructive testing5*

Destructive tests

Ssubsurface discontinuities

Butt

Trans

Butt

Fat 39 Fat 49

2 (3 macrosections) 5 (3 macrosections)

Longl

Butt

Fat 61

2 (3 macrosections)

Cruciform

Longl

Butt

Fat 49

2 (3 macrosections)

Fillet

Fat 49

2 (3 macrosections + 2 fractures tests)

NOTE 1: Where less than 100% of the joints are to be inspected the sample should include at least one weld from each joint where a different welding procedure is required. In the case of destructive tests at least two welds from each joint should be included. In any case at the start of production the first five joints of each type should be inspected. In the event of a non-compliance with table D.2 being found a further five joints should be tested before reverting to the recommended partial inspection. Where there is no specific recommendation for non-destructive testing this is indicated with a hyphen.

NOTE 2: Where access for inspection of a joint may be eliminated by subsequent work prior to completion of all welding, that joint should be inspected before that work is carried out.

NOTE 3: W/E-within 20mm of weld end; S/S within 20mm of a stop or start; DF applies only where weld caps have to be dressed flush.

NOTE 4: Trans - transverse, Longl - longitudinal. Transverse applies to all welds whose axes are orientated at an angle greater than 45° to the longitudinal axis of the member. Welds whose angles are less than 45° are treated as longitudinal. All welds within 100mm of the connection between load-carrying members or main loading points are treated as transverse.

NOTE: Radiography may be used in place of ultrasonic inspection for detecting purposes. However, ultrasonic inspection may be required for assessment of the compliance of discontinuities with table D.2.

NOTE: Where run-off test plates are used for destructive testing they should be located so that they comply with footnote 1. Where production components are to be sampled for destructive tests, the appropriate additional number of components should be made at the time of production.

D.1.4 Quality Levels

D.1.4.1 General quality control

(1) EN 30042 - Level B shall be used as a general guide for the purpose of identifying lapses in assembly or welding control.

D.1.4.2 Final acceptance

(1) The required quality levels for final acceptance of production welds and any corrective actions shall be in accordance with Table D.2, for the purposes of avoiding unnecessary repair.

Table D.2. Acceptance levels for production welds

Feature

Parameter

Weld type

Particular conditions0

Figure

reference

Dimensions

Acceptance criteria according to required quality level2)'3)'4)

Corrective actions5*

Normal

Fat 25

Fat 31

Fat 39

Fat 49

Fat 62

Overall weld geometry

Location 6)

All

D± 10

D±5

D±5

D± 5

D± 5

D± 5

E

Weld type

All

D

D

D

D

D

D

E

Extent (length)

All

D+10-0

D+10-0

D+10

D+10-0

D+10-0

D+10-0

E

Profile discontinuities

Actual throat thickness

All

i, ii, iii

a,<

D(50) D + 5

D + 4

D + 4

D + 3

D + 3

D + 3

R DS

Leg length

Fillet

i

z>

D(50)

D(50)

D(50)

D

D

D

R

Toe angle (interface and interrun)

All

Trans Longl

9 >

90° 90°

120° 90°

150° 90°

165° 90°

175° 90°

175°

DS/R DS/R

Excess weld metal

Butt

Trans Longl

ii ii

h<; h <

6 6

6

5

2 4

0.5 3

0.5

DS DS

Incomplete groove or concave root

Butt

Trans Longl

ii ii

h< h <

0(50) 0,lt

NP 0,lt

NP 0,lt

NP 0,lt

NP 0,05t

NP

R R

All

Trans, butt Trans, cruciform Longl

iv, V

h< h < h <

D + 0.2t D + 0.4t D + 0.4t

D + 0,lt D + 0,2t D + 0,4t

D+0,05t D+0,4t

D + 0,05t D + 0,4t

D + 0,05t D + 0,4t

D + 0,4t

E E E

Surface breaking discontinuities

All

Trans (not lap joint) Trans (lap joint)

Long

0,03t 10 0,lt

0,05t

0,05t

R R R R R

Lack of root penetration

S/S butt

Trans Longl

iii iii

h< h<

D + 0,05t (50) D + 0,01t (50)

D + 0,lt

D + 0,lt

D + 0,05t

D + 0,05t

-

R R

Porosity

All

Trans Longl

vi vi

d£ Id< d < Zd<

5 [100]

NP NP NP NP

NP NP

R R R R

Lack of fusion

All

vii

1<

NP

NP

NP

NP

NP

NP

R

Cracks

All

1<

NP

NP

NP

NP

NP

NP

continued/

Table D.2. Acceptance levels for production welds (continued)

Feature

Parameter

Weld type

Particular conditions0

Figure

reference

Dimensions

Acceptance criteria according to required quality level2)'3)> 4)

Corrective actions5)

Normal (Fat 20)

Fat 25

Fat 31

Fat 39

Fat 49

Fat 62

Sub-surface discontinuities

Lack of fusion root penetration

Butt

All

vii, viii

h<

3

3

3

3

3

NP

R

h1 >6

vii, viii vii, viii

Il< 1< ll> 1< l'>

l,5t [100] 10 10 NL NL

l,5t [100] 5 10 10 10

NP NP NP 5 10

NP NP NP NP

NP NP NP NP NP

NP NP NP NP NP

R R R R R

hl >6

vii, viii vii, viii vii, viii

NL

l,5t [100] 10 NL NL NL

NL

NP NP NP NP NL

R R R R R

Root gap

Fillet/ PPbutt

l,v

h<

2(100) 3

2

2

2

2

1

R

Copper inclusion

All

NA

NA

NP

NP

NP

NP

R

Solid and other inclusions

All

d<

NA

NA

2

1

NP

NP

R

Porosity

All

vi, vii

d< A <

NA

NA

3%

2%

1%

NP NP

R R

Cracks

All

NP

NP

NP

NP

NP

NP

R

NOTE 1. For definition of orientation see footnote 4 in table D. 1.

NOTE 2. All dimensions are in millimetres unless otherwise noted.

NOTE 3. Thickness applies to minimum member thickness at weld in question.

For thicknesses greater than 20mm t is taken as 20mm. Where the permitted size h of a discontinuity is related to t the maximum permitted value is not less than

0.3mm in any case.

NOTE 4. Where more than one value is given both apply. NOTE 5. See Note 1 in table D. 1.

NL

Dimension specified on drawings Dress smoothly Refer to designer No limit

SS Single sided, (including butt welds in hollow sections)

( ) Length of weld, over which measurement may be averaged (in mm)

[ ] Length of weld, over which the summation is made [in mm]

NOTE 6. Subject to any other locational requirements.

NOTE 7. 'lap' applies to any fillet welded attachment whose length in the longitudinal direction exceeds 50mm.

NP Not permitted (applies to discontinuities which are detectable by non-destructive test methods in table D. 1).

PP Partial penetration

NA Not normally applicable (see table D1) _Not applicable (see tables 5.1.2 and 5.1.3)

A Percentage area (of porosity) as seen on radiograph in any 100mm of weld length

NOTE 8. Any straight line parallel to the weld axis.

R

Repair by welding to approved procedure

1 Length parallel to weld axis

Attachment length
|<-1-1

->

d

f

c

f

tl

c

<-

r>

nl o

r\

AV 6 ~ ♦ ♦

<*

Welding Discontinuity Image
Section X-X in g)

Fig.D.2.1. Dimensions of weld discontinuities

D.2 Castings

D.2.1 Methods and Extent of Inspection

(1) The methods and minimum extent of inspection shall be in accordance with table D.3 for the purposes of final inspection of the work.

Table D.3 Scope of inspection for castings

Required quality level

Type of Inspection

Surface

Volumetric

Normal

100% visual

«

Fat 25

100% dye penetrant

10 % Radiography

Fat 31

100% dye penetrant

100% Radiography

Fat 39

100% dye penetrant

100% Radiography

Fat 49

100% dye penetrant

100% Radiography

Fat 62

100% dye penetrant

100% Radiography

Fat 77

100% dye penetrant

100% Radiography

D.2.2 Final Acceptance

(1) The required quality levels for final acceptance of castings shall be as in table D.4.

Table D.4 Quality levels for castings

Required quality level

Type of Discontinuity

Cracks

Maximum pore size (mm)

Normal

Not Permitted

3,0

Fat 25

Not Permitted

2,2

Fat 31

Not Permitted

1,5

Fat 39

Not Permitted

0,9

Fat 49

Not Permitted

0,5

Fat 62

Not Permitted

0,3

Fat 77

Not Permitted

0,2

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