2 - NR 476 - Approval Testing of Welders - November 2001

7/30/2019 2 - NR 476 - Approval Testing of Welders - November 2001

1/15

APPROVAL TESTING of WELDERS

Rule NoteNR 476 DTM R00 E

November 2001

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2/15

MARINE DIVISION GENERAL CONDITIONS

BV Mod. Ad. ME 545 h - 06/2000

ARTICLE 1

1.1. - BUREAU VERITAS is a Society the purpose of whose Marine Division (theSociety) is the classification ( Classification ) of any ship or vessel or structure of anytype or part of it or system therein collectively hereinafter referred to as a Unit whetherlinked to shore, river bed or sea bed or not, whether operated or located at sea or ininland waters or partly on land, including submarines, hovercrafts, drilling rigs, offshoreinstallations of any type and of any purpose, their related and ancillary equipment, subseaor not, such as well head and pipelines, mooring legs and mooring points or otherwise asdecided by the Society.The Society: prepares and publishes Rules for classification, Guidance Notes and other

documents ( Rules );

issues Certificates, Attestations and Reports following its interventions( Certificates );

publishes Registers.

1.2. - The Society also participates in the application of National and International

Regulations or Standards, in particular by delegation from different Governments. Thoseactivities are hereafter collectively referred to as Certification .

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ARTICLE 2

2.1. - Classification is the appraisement given by the Society for its Client, at a certain

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classes Units and enters their name in its Register;

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and certificates which have been prepared for them;

copy of the documents made available for the classification of the Unit can behanded over to another Classification Society Member of the InternationalAssociation of Classification Societies (IACS) in case of the Units transfer of class;

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diverging opinions during surveys.

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ARTICLE 13

13.1. - These General Conditions constitute the sole contractual obligations binding

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13.2. - The invalidity of one or more stipulations of the present General Conditions does

not affect the validity of the remaining provisions.

13.3. - The definitions herein take precedence over any definitions serving the same

purpose which may appear in other documents issued by the Society.


3/15

November 2001

RULE NOTE NR 476

APPROVAL TESTING of WELDERS

Section 1 Approval Testing and Certification of Welders for Fusion Welding


4/15

2 Bureau Veritas November 2001

NR 476 Approval Testing of Welders

Section 1 Approval Testing and Certification of Welders for Fusion Welding

1 General 3

1.1

2 Welders employed for steel hull 3

2.1 Variables for approval testing2.2 Range of approval2.3 Welding of approval test pieces2.4 Examinations and tests2.5 Certification

3 Welders employed for aluminium alloys structures 83.1 Variables for approval testing3.2 Range of approval3.3 Welding of approval test pieces3.4 Examinations and tests3.5 Certification

4 Welders employed for other productions 12

4.1 Approval tests and range of approval4.2 Certification


5/15

NR 476, Sec 1

November 2001 Bureau Veritas 3

SECTION 1 APPROVAL TESTING AND CERTIFICATION OFWELDERS FOR FUSION WELDING

1 General

1.1

1.1.1 This document gives approval testing conditions,

acceptance requirements and range of approval of welders

employed for fusion welding when specified by Bureau Ver-

itas Rules for the Classification of Steel Ships.

1.1.2 Approval testing of welder is required for fusion

welding processes designated as manual or semi-automatic

welding processes where the quality of the welded joint

depends mainly on the manual skill of the welder. Opera-

tors using fully mechanized and fully automatic welding

processes are to be suitably trained and experienced.

1.1.3 After satisfactory completion of approval tests under

the supervision of a Society surveyor, the Society will issue

an approval certificate on appropriate form (see annex).

1.1.4 Alternative standards or procedures for approval test-

ing considered as equivalent to the provisions set in this

document may be used upon special consideration of theSociety.

2 Welders employed for steel hull

2.1 Variables for approval testing

2.1.1 Welding processes

Manual or semi-automatic welding processes commonlyused are listed as follows :

Metal arc welding with covered electrodes (SMAW, ISO

4063 ref. number 111)

Metal arc inert gas welding (MIG, ISO 4063 ref. number

131)

Flux cored wire metal arc welding with active gas shield

or without gas shield (FCAW, ISO 4063 respective ref.number 136 and 114)

Change of welding process shall require new approval test-

ing.

2.1.2 Welding consumables

In general approval tests are carried out using filler metal of

grade matching the base material strength.

2.1.3 Type of weld joint

A change of type of weld joint to type for which the welder

is not approved shall require new approval testing.

2.1.4 Type and dimensions of base products

Welding of base products with dimensions out of theapproved range shall require new approval testing.

2.1.5 Welding position

A change in the position of welding to one for which the

welder is not approved shall require new approval testing.

The welding positions for plates are identified in Fig 3.

2.2 Range of approval

2.2.1 Welding process

Approval tests are to be performed for each process.


Approval is extended to the use of any consumables similar

to the type used for the approval tests and suitable for the

materials to be welded and processes used.

A change in the type of covered electrode may require a

change in the welders technique. Approval tests performedwith a type of covered electrode may extend approval to the

use of other types of covered electrode as specified in Tab

1.

Table 1 : Range of approval for electrode coating

2.2.3 Range of thickness

According to the thickness of approval test pieces, the range

of approval for plate thickness is given in table 2. The limits

are not to be understood as strict conditions.

Table 2 : Approval test piece thickness and range of

approval

Type of covered electrode

used for approval test pieces

Type of covered electrode

which may be used for pro-

duction work

Acid or rutile-acid covering Acid or rutile-acid covering

Rutile or rutile-basic or

rutile-cellulosic or rutile-

thick covering

Acid or rutile-acid covering

or rutile or rutile-basic or


thick covering

Basic covering Acid or rutile-acid covering

or rutile or rutile-basic or


thick covering or basic cov-

ering

Cellulosic covering Cellulosic covering

Approval test piece thick-

ness t (mm)

Range of approval for pro-

duction works

t 3 mm t to 2 t

3 mm < t 12 mm 3 mm to 2 t

t > 12 mm t 5 mm


6/15

NR 476, Sec 1


2.2.4 Welding positions and type of weld joint andproducts

Approval tests performed on butt welds in horizontal (PC),

vertical upwards (PF), overhead (PE) positions and on fillet

welds in horizontal overhead (PD), vertical upwards (PF)

positions extend approval to butt and fillet production

welding in all positions except vertical downwards. This setof tests also extends approval to production fillet welding of

fixed hollow sections to plate in positions PB, PF and PD as

shown in Fig 4.


vertical upwards (PF) positions and on fillet welds in vertical

upwards (PF) position extend approval to butt and fillet pro-

duction welding in positions tested and in flat (PA) and hor-

izontal vertical (PB) positions. This set of tests also extendsapproval to production fillet welding of fixed hollow sec-

tions to plate in positions PB and PF as shown in Fig 4.

Other sets of approval tests confer approval for production

welding in positions tested and type of joint welded.

2.2.5 Steel category

Base materials for approval tests are to be of normal

strength (grades A, B, D or E) or higher strength (AH32 to

FH40) hull steel grades. Approval is extended to production

welding of all hull steel grades.

2.2.6 Backing and gouging conditions

Backing and gouging range of approval is as follows :

Satisfactory approval test pieces welded from one sidewithout backing extend approval to welding from one

side with backing and welding from both sides with or

without gouging.

Satisfactory approval test pieces welded from one sidewith backing extend approval to welding from both

sides with gouging.

Satisfactory approval test pieces welded from both sides

without gouging extend approval to welding from oneside with backing and welding from both sides with

gouging.

2.3 Welding of approval test pieces

2.3.1 General

The welder is to have suitable practical experience and pro-

fessional knowledge of the welding process including the

regulation of the parameters of the welding equipment used

The surveyor may stop the test if the welding conditions are

not correct or if it appears that the welder does not have the

technical competence to achieve the required standard.

2.3.2 Number, shape and dimensions of test pieces

The number, shape and dimensions of test pieces madewith plates are to be selected so as to cover the production

welding work taking into account the welding variables in

[2.1] and the range of approval in [2.2].

The shape and dimensions of test pieces are shown in Fig 1and Fig 2.

Figure 1 : Dimensions of test piecefor a butt weld in plate

(dimensions in mm)

Figure 2 : Dimensions of test piecefor fillet weld(s) on plate

(dimensions in mm)

2.3.3 Welding conditions

The approval tests are to correspond to the conditions used

in production welding and follow a welding procedure

specification representative of production practice.

3

0

0

t

1 2 5 1 2 5

t

12

5

t

1 2 5

1

5

0

z

a

z = a 2

F o r t 6 m m a 0 , 5 t F o r t < 6 m m 0 , 5 t a t( z ~ 0 , 7 t )

~


7/15

NR 476, Sec 1


In general the following condition apply :

The time for the welding of the test piece is to corre-

spond to the usual working condition;

The test piece shall have at least one stop and restart in

the root run and in the top capping run which has to beidentified for further examination;

Any preheat or controlled heat input specified in thewelding procedure is required for the test piece;

Any post-weld heat treatment specified in the weldingprocedure may be omitted unless bend tests are

required;

The test pieces are to be suitably identified with the

mark of the surveyor and the identification of the welder

before welding starts;

The welder is allowed to remove minor imperfections,

except on the surface layer, by grinding or any other

method used in production upon surveyor's agreement;

The appearence of each pass, both for butt and fillet

welds, is to be of appropriate geometry and practically

free from undercuts, convexities and sizeable local

defects; the surface is to be sufficiently regular.

Similarly the back of the weld is to be free from sizeable

undercuts, excessive convexities and lack of penetra-

tion; in particular for the welders to be qualified for one

side welding without backing the root penetration of the

samples is to be regular and constant.

Figure 3 : Welding positions for plates

P B H o r i z o n t a l v e r t i c a l

P A F l a t

P G V e r t i c a l d o w n w a r d s

P E O v e r h e a d

P C H o r i z o n t a l

P F V e r t i c a l u p w a r d s

P A F l a t

P D H o r i z o n t a l o v e r h e a d

P G V e r t i c a l d o w n w a r d s

P F V e r t i c a l u p w a r d s

a ) B u t t w e l d s

b ) F i l l e d w e l d s


8/15

NR 476, Sec 1


Figure 4 : Welding positions for hollow sections

2.4 Examinations and tests

2.4.1 General

The non destructive examinations and destructive tests to be

performed are indicated in Tab 3.

Prior to mechanical tests, backing strips where used are to

be removed. The test piece can be sectioned by thermal

cutting or by mechanical means discarding the first and last

25mm of the test piece at the end of the plates.

Table 3 : Examinations and tests

P i p e : r o t a t i n g

A x i s : h o r i z o n t a l

W e l d : h o r i z o n t a l v e r t i c a l

2 *

P i p e : f i x e d

A x i s : h o r i z o n t a l

W e l d : v e r t i c a l u p w a r d s

2 .

P i p e : f i x e d

A x i s : v e r t i c a l

W e l d : h o r i z o n t a l o v e r h e a d

2 ,

Type of examination or test

Extent of the examination or test

Butt weld plate Fillet weld

Visual examination 100% 100%

Radiographic test 100% (1)

Bend tests (2) 2 face, 2 root

Fracture tests 1 sample (1) 1 sample (3) (4)

Macroexamination 4 sections (4)

(1) Radiographic or fracture test is to be used (not both).

(2) For processes 131 (MIG) and 135 (MAG), bend tests are mandatory when radiography is used; face and root bend tests may be

substituted by 4 side bend tests for t 12 mm.

(3) Magnetic particle/liquid penetrant tests are also to be carried out if required by the surveyor

(4) The fracture test may be replaced by a macro examination, one of which in start/stop position.


9/15

NR 476, Sec 1


2.4.2 Test pieces and test specimens

Details of the type, dimensions and preparation of testpieces and test specimens are given in Fig 5 and Fig 6.

For butt welds in plates, the following conditions apply :

When radiographic test is used the inspection length of

the weld in the test pieces shall be radiographed in theas-welded condition in accordance with ISO 1106-1 orISO 1106-2 using class B technique;

When fracture testing is used, the full test piece inspec-tion length shall be tested and to do this, the test piece

shall be cut into several test specimens (Fig 5a). The

length of any fracture test specimen shall be about

50mm. If necessary, the weld reinforcement of the test

specimen may be removed and additionally the weld

edges may be notched to a depth of about 5mm to ini-tiate fracture in the weld metal (Fig 7b). In the case of

single-sided welding without backing, half of the

inspection length shall be tested against the face sideand the other half against the root side (Fig 5c and 5d).

When transverse bend testing is used for plate thickness

greater than 3mm, 2 root bend test specimens and 2face bend test specimens shall be tested in accordance

with EN 910 or equivalent standard. The mandrel diam-

eter is to be 4t and the bending angle at least 120.

For plate thickness greater than 12mm, the transverse

bend tests may be substituted by 4 side bend tests.

For fillet welds on plates, the following conditions apply :

For fracture tests the test piece may be cut, if necessary,into several test specimens (see Fig 6a). Each test speci-

men shall be positioned for breaking as shown in Fig 6b,

and examined after fracture.

When macro examination is used, 4 test specimens

shall be taken equally spaced in the inspection length.

Figure 5 : Preparation and fracture testing of test specimens for a butt weld in plate

(dimensions in mm)

2

2 5

2 5

I n s p e c t i o n l e n g t h

o f t h e t e s t p i e c e

1

1

a ) S e c t i o n i n g i n t o a n e v e n - n u m b e r e d q u a n t i t y

o f t e s t s p e c i m e n s

b ) P r e p a r a t i o n

c ) F r a c t u r e t e s t i n g f a c e b e n d t e s t d ) F r a c t u r e t e s t i n g r o o t b e n d t e s t


o f t e s t s p e c i m e n

~

2

~

~ 5 0

~

~ 5

~

~ 5

~

~

2

~


10/15

NR 476, Sec 1


Figure 6 : Preparation and fracture testing of test specimens for a fillet weld on plate

(dimensions in mm)

2.4.3 Acceptance criteria

During the testing for butt welds in plates, the test speci-

mens are not to reveal any open defect, in any direction,greater than 3mm. Defects appearing at the corner of the

test specimen may be disregarded.

The acceptance requirements for imperfections found by

visual and radiographic examination or fracture are to be

assessed in accordance with ISO standard 5817.

The imperfections are to be within the specified limits of

level B in ISO standard 5817 except for imperfections type

as follows : excess weld metal, excessive convexity, excess

throat thickness and excessive penetration, for which level

C is acceptable.

2.4.4 Re-testing

The test sample is to be repeated if any test piece fails to

comply with the requirements.

When the failure of the repeated test is due to the welder

lack of skill, the welder is to be adequately trained and usu-ally will not be permitted to perform new approval tests

unless at least a month has elapsed since the previous

examination.

2.5 Certification

2.5.1 General

Upon satisfactory completion of the approval tests an

approval certificate is issued stating approval tests per-

formed and range of approval.

2.5.2 Initial approval

The validity of the welders approval begins from the date

when all the required tests are satisfactorily completed.

The approval shall remain valid for a period of two years

unless the welder is not engaged in a given welding process

for which he is approved for a period exceeding six months

and unless there is specific reason to question the welders

ability. The employer/welding supervisor is to endorse therelevant certificate at six months interval to confirm that theconditions of validity are fulfilled.

2.5.3 Prolongation

In order to renew the certificate for another two-year

period, approval tests as per initial approval are to be per-

formed. Alternative procedure may be used upon special

consideration by the Society.

Approval tests may be reduced where records of X-ray or

ultrasonic inspections or test reports about fracture tests

from production welds made by the welder are available

and maintained on file with the welders approval certifi-cate.

3 Welders employed for aluminiumalloys structures

3.1 Variables for approval testing

3.1.1 Welding processes

Manual or semi-automatic welding processes commonly

used are listed as follows :

Metal arc inert gas welding (MIG, ISO 4063 ref. number

131)

Tungsten inert gas welding (TIG, ISO 4063 ref. number

141)

Change of welding process shall require new approval test-

ing.


Approval tests are to be carried out using suitable filler

metal and gas shield compatible with the parent metal and

the process.

3.1.3 Type of weld joint

A change of type of weld joint to type for which the welder

is not approved shall require new approval testing.

3.1.4 Type and dimensions of base products

Welding of base products with dimensions out of theapproved range shall require new approval testing.

2

5

b ) F r a c t u r e t e s t i n g

( T h e f i l l e t w e l d m a y b e n o t c h e d i f n e c e s s a r y )


o f f i l l e t w e l d

a ) S e c t i o n i n g i n t o a n e v e n - n u m b e r e d

q u a n t i t y o f t e s t s p e c i m e n s

2

5


11/15

NR 476, Sec 1


3.1.5 Welding position

A change in the position of welding to one for which the

welder is not approved shall require new approval testing.

The welding positions for plates are identified in Fig 3.

3.2 Range of approval

3.2.1 Welding process

Approval tests are to be performed for each process.


Approval is extended to the use of any consumables similar

to the type used for the approval tests and suitable for the

materials to be welded and processes used.

3.2.3 Range of thickness

According to the thickness of approval test pieces, the range

of approval for plate thickness is given in table 4. The limits

are not to be understood as strict conditions.

Table 4 : Approval test piece thickness and range of

approval

3.2.4 Welding positions and type of weld joint andproducts

Approval tests performed on butt welds in horizontal (PC),vertical upwards (PF), overhead (PE) positions and on fillet

welds in horizontal overhead (PD), vertical upwards (PF)

positions extend approval to butt and fillet production

welding in all positions except vertical downwards. This setof tests also extends approval to production fillet welding of

fixed hollow section to plate in positions PB, PF and PD as

shown in Fig 4.


vertical upwards (PF) positions and on fillet welds in vertical

upwards (PF) position extend approval to butt and fillet pro-duction welding in positions tested and in flat (PA) and hor-

izontal vertical (PB) positions. This set of tests also extends

approval to production fillet welding of fixed hollow sec-tion to plate in positions PB and PF as shown in Fig 4.

Other sets of approval tests confer approval to productionwelding in positions tested and type of joint welded.

3.2.5 Aluminium alloys category

Approval tests are made on plates of a typical marine alu-minium alloy grade (usual 5083, 5086, 5754) and confer

approval to production welds on plates and/with extruded

products made of alloys 6005A, 6061and 6082.

3.2.6 Backing and gouging conditions

Backing and gouging range of approval is as follows :

Satisfactory approval test pieces welded from one sidewithout backing extend approval to welding from one

side with backing and welding from both sides with orwithout gouging.

Satisfactory approval test pieces welded from one side

with backing extend approval to welding from both

sides with gouging.

Satisfactory approval test pieces welded from both sideswithout gouging extend approval to welding from oneside with backing and welding from both sides with

gouging.

3.3 Welding of approval test pieces

3.3.1 General

The welder is to have suitable practical experience and pro-

fessional knowledge of the welding process including the

regulation of the parameters of the welding equipment used

The surveyor may stop the test if the welding conditions are

not correct or if it appears that the welder does not have thetechnical competence to achieve the required standard.

3.3.2 Number, shape and dimensions of test pieces

The number, shape and dimensions of test pieces made

with plates are to be selected so as to cover the production

welding work taking into account the welding variables in

[3.1] and the range of approval in [3.2].

The shape and dimensions of test pieces required are shown

in Fig 7 and Fig 8.

Figure 7 : Dimensions of test piecefor a butt weld in plate

(dimensions in mm)

Approval test piece thick-

ness t (mm)

Range of approval for pro-

duction works

t 6 mm 0,7 t to 2,5 t

6 mm < t 15 mm 6 mm to 40 mm

3

0

0

t

1 5 0 1 5 0


12/15

NR 476, Sec 1


Figure 8 : Dimensions of test piecefor fillet weld(s) on plate

(dimensions in mm)

3.3.3 Welding conditions

The approval tests are to correspond to the conditions usedin production welding and follow a welding procedure

specification representative of production practice.

In general the following condition apply :

The time for the welding of the test piece is to corre-

spond to the usual working condition;

The test piece shall have at least one stop and restart inthe root run and in the top capping run which has to be

identified for further examination;

Any preheat or controlled heat input specified in the

welding procedure is required for the test piece;

The test pieces are to be suitably identified with the

mark of the surveyor and the identification of the welderbefore welding starts;

The welder is allowed to remove minor imperfections,except on the surface layer, by grinding or any other

method used in production upon surveyor's agreement;

The appearence of each pass, both for butt and fillet

welds, is to be of appropriate geometry and practically

free from undercuts, convexities and sizeable localdefects; the surface is to be sufficiently regular.

Similarly the back of the weld is to be free from sizeableundercuts, excessive convexities and lack of penetra-

tion; in particular for the welders to be qualified for one

side welding without backing the root penetration of the

samples is to be regular and constant.

3.4 Examinations and tests

3.4.1 General

The non destructive examinations and destructive tests to be

performed are indicated in Tab 5.

Prior to mechanical tests, backing strips where used are to

be removed. The test piece can be sectioned by thermal

cutting or by mechanical means discarding the first and last

25mm of the test piece at the end of the plates.

3.4.2 Test pieces and test specimens

Details of the type, dimensions and preparation of testpieces and test specimens are given in Fig 9 and Fig 10.

For butt welds in plates, the following conditions apply :

When radiography is used the inspection length of the

weld in the test pieces shall be radiographed in the as-

welded condition in accordance with ISO 2437 using

class B technique;

When fracture testing is used, the full test piece inspec-

tion length shall be tested and to do this, the test piece

shall be cut into several test specimens (Fig 5a). The

length of any fracture test specimen shall be about50mm. If necessary, the weld reinforcement of the test

specimen may be removed and additionally the weld

edges may be notched to a depth of about 5mm to ini-tiate fracture in the weld metal (Fig 7b). In the case of

single-sided welding without backing, half of the

inspection length shall be tested against the face sideand the other half against the root side (Fig 5c and 5d).

When transverse bend testing is used for plate thicknessgreater than 3mm, 2 root bend test specimens and 2

face bend test specimens shall be tested. The mandrel

diameter is to be 6t for alloys 5083, 5086 and 5383, 7t

for alloys 6005A, 6061 and 6082 in temper condition

T5 or T6 and the bending angle 180.

For plate thickness greater than 12mm, the transverse

bend tests may be substituted by 4 side bend tests.

For fillet welds on plates, the following conditions apply :

For fracture tests the test piece may be cut, if necessary,

into several test specimens (see Fig 6a). Each test speci-men shall be positioned for breaking as shown in Fig 6b,

and examined after fracture.

When macro examination is used, 4 test specimens

shall be taken equally spaced in the inspection length.

t

1

5

0

t

1 5 0

3

0

0

z

a

z = a 2

F o r t 6 m m a 0 , 5 t

F o r t < 6 m m 0 , 5 t a t

( z ~ 0 , 7 t )

~


13/15

NR 476, Sec 1


Table 5 : Examinations and tests

Figure 9 : Preparation and fracture testing of test specimens for a butt weld in plate

(dimensions in mm)

Type of examination or test

Extent of the examination or test

Butt weld plate Fillet weld

Visual examination 100% 100%

Radiographic test 100% (1)

Bend tests (2) 2 face, 2 root

Fracture tests 1 sample (1) 1 sample (3) (4)

Macro examination 4 sections (4)

(1) Radiographic test or fracture test is to be used (not both).

(2) Only mandatory in addition to radiographic test for process 131 (MIG).

(3) When required by the surveyor, liquid penetrant examination is also to be carried out.

(4) The fracture test may be replaced by a macro examination, one of which in start/stop position.

2

2 5

2 5


o f t h e t e s t p i e c e

1

1

a ) S e c t i o n i n g i n t o a n e v e n - n u m b e r e d q u a n t i t y

o f t e s t s p e c i m e n s

b ) P r e p a r a t i o n

c ) F r a c t u r e t e s t i n g f a c e b e n d t e s t d ) F r a c t u r e t e s t i n g r o o t b e n d t e s t


o f t e s t s p e c i m e n

~

2

~

~ 5 0

~

~ 5

~

~ 5

~

~

2

~


14/15

NR 476, Sec 1


Figure 10 : Preparation and fracture testing of test specimens for a fillet weld on plate

(dimensions in mm)

3.4.3 Acceptance criteria

During the testing for butt welds in plates, the test speci-

mens are not to reveal any open defect, in any direction,

greater than 3mm. Defects appearing at the corner of thetest specimen may be disregarded.

The acceptance requirements for imperfections found by

visual and radiographic examination or fracture are to be

assessed in accordance with ISO standard 10042.

The imperfections are to be within the specified limits of

level B in ISO standard 10042 except for imperfections type

as follows : excess weld metal, excessive convexity, excess

throat thickness and excessive penetration, for which levelC is acceptable.

3.4.4 Re-testing

The test sample is to be repeated if any test piece fails to

comply with the requirements.

When the failure of the repeated test is due to the welder

lack of skill, the welder is to be adequately trained and usu-ally will not be permitted to perform new approval tests

unless at least a month has elapsed since the previous

examination.

3.5 Certification

3.5.1 General

Upon satisfactory completion of the approval tests an

approval certificate is issued stating approval tests per-formed and range of approval.

3.5.2 Initial approval

The validity of the welders approval begins from the date

when all the required tests are satisfactorily completed.

The approval shall remain valid for a period of two years

unless the welder is not engaged in a given welding process

for which he is approved for a period exceeding six monthsand unless there is specific reason to question the weldersability. The employer/welding supervisor is to endorse the

relevant certificate at six months interval to confirm that the

conditions of validity are fulfilled.

3.5.3 Prolongation

In order to renew the certificate for another two-year

period, approval tests as per initial approval are to be per-

formed. Alternative procedure may be used upon special

consideration by the Society.

Approval tests may be reduced where records of X-ray or

ultrasonic inspections or test reports about fracture tests

from production welds made by the welder are availableand maintained on file with the welders approval certifi-

cate.

4 Welders employed for other produc-tions

4.1 Approval tests and range of approval

4.1.1 For productions not included in [2] and [3] (such assome welded components, boilers and pressure vessels,

pressure piping systems...), the extent of the approval tests

and examinations with their acceptance criteria and therange of approval are to be based on the relevant require-

ments of a suitable standard recognized by the Society, e.g.

ISO 9606 series, EN 287 series, ASME Section IX,ANSI/AWS D1.1.

4.2 Certification

4.2.1 Upon satisfactory completion of the approval tests

performed under the supervision of a Society surveyor an

approval certificate is issued stating approval tests per-

formed and range of approval.

4.2.2 The conditions set in [2.5.2] and [2.5.3] are applica-ble.

2

5

b ) F r a c t u r e t e s t i n g

( T h e f i l l e t w e l d m a y b e n o t c h e d i f n e c e s s a r y )


o f f i l l e t w e l d

a ) S e c t i o n i n g i n t o a n e v e n - n u m b e r e d

q u a n t i t y o f t e s t s p e c i m e n s

2

5


15/15

NR 476, Sec 1

13

ANNEX Form of the approval certificate

Certificate number :

Employer's name and address :

Welder's name :

Identification :

Method of identification :

Date and place of birth :

Production type Steel hull Aluminium alloys structures Others (1)

(1) Approval conditions are based on following recognized standard :

Type of test and examination

Visual examination

Radiography test

Magnetic particle test

Dye penetrant test

Macrography

Fracture test

Bend test

Others

Welding variables

Welding process

Welding consumable

Base material group

Type of base product

Type of weld joint

Range of thickness

Welding positions

Backing and gouging condition

Others

Date and place of issue : This certificate expires on :

BV Mod. Ad.E 636 - 10/01

This Certificate is delivered within the scope of the General Conditions of BUREAU VERITAS Marine Division. Any person not a party to the contract

pursuant to which this document is delivered may not assert a claim against Bureau Veritas for any liability arising out of errors or omissions which may be

contained in said document, or for errors of judgment, fault or negligence commited by personnel of the Society or of its Agents in establishment or issuance

of this document, and in connection with any activities for which it may provide.

Employer's endorsment to confirm the validity for the following

six months (date, name, position, signature) :

This is to attest that the welder identified above has passed the approval tests, under the supervision of Bureau

Veritas, in accordance with Rule Note NR 476 and Bureau Veritas Rules for the Classification of Steel ships.

WELDER APPROVAL TEST CERTIFICATE

according to Bureau Veritas Rules

Manufacturer's Welding Procedure(s) Specification number

for the Classification of Steel Ships

Range of approval

Welder's

photograph

(optional)

Surveyor's name, signature and stamp :

Not performed / Performed & Test report number

2 - NR 476 - Approval Testing of Welders - November 2001

Documents

Transcript of 2 - NR 476 - Approval Testing of Welders - November 2001