ensayos para aprobar soldadores

APPROVAL TESTING of WELDERS

Rule NoteNR 476 DTM R00 E

November 2001

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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 (the“Society”) 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 InternationalRegulations or Standards, in particular by delegation from different Governments. Thoseactivities are hereafter collectively referred to as « Certification ».

1.3. - The Society can also provide services related to Classification and Certificationsuch as ship and company safety management certification; training activities; allactivities and duties incidental thereto such as documentation on any supporting means,software, instrumentation, measurements, tests and trials on board.

1.4. - The interventions mentioned in 1.1., 1.2. and 1.3. are referred to as « Services ».The party and/or its representative requesting the services is hereinafter referred to as the« Client ».

The Services are prepared and carried out on the assumption that the Clients areaware of the International Maritime and/or Offshore Industry (the “Industry”)practices.

1.5. - The Society is neither and may not be considered as an Underwriter, Broker inship’s sale or chartering, Expert in Unit’s valuation, Consulting Engineer, Controller, NavalArchitect, Manufacturer, Shipbuilder, Repair yard, Charterer or Shipowner who are notrelieved of any of their expressed or implied obligations by the interventions of theSociety.

ARTICLE 2

2.1. - Classification is the appraisement given by the Society for its Client, at a certaindate, following surveys by its Surveyors along the lines specified in Articles 3 and 4hereafter on the level of compliance of a Unit to its Rules or part of them. Thisappraisement is represented by a class entered on the Certificates and periodicallytranscribed in the Society’s Register.

2.2. - Certification is carried out by the Society along the same lines as set out in Articles3 and 4 hereafter and with reference to the applicable National and InternationalRegulations or Standards.

2.3. - It is incumbent upon the Client to maintain the condition of the Unit aftersurveys, to present the Unit for surveys and to inform the Society wit hout delay ofcircumstances which may affect the given appraisement or cause to modify itsscope.

2.4. - The Client is to give to the Society all access and information necessary for theperformance of the requested Services.

ARTICLE 3

3.1. - The Rules, procedures and instructions of the S ociety t ake into a ccount at thedate of their preparation the state of currently available and proven technicalknowledge of the Industry. They are not a code of construction neither a guide formaintenance or a safety handbook.

Committees consisting of personalities from the Industry contribute to the development ofthose documents.

3.2. - The Society only is qualified to apply its Rules and to interpret them. Anyreference to them is void unless it involves the S ociety’s intervention.

3.3. - The Services of the Society are carried out by professional Surveyors according tothe Code of Ethics of the Members of the International Association of ClassificationSocieties (IACS).

3.4. - The operations of the Society in providing its Services make use of randominspections and are absolutely exclusive of any monitoring and thorough verification.

ARTICLE 4

4.1. - The Society, acting by reference to its Rules:• reviews the construction arrangements of the Units as shown on the documents

presented by the Client;• conducts surveys at the place of their construction;• classes Units and enters their name in its Register;• surveys periodically the Units in service to note that the requirements for the

maintenance of class are met.

The Client is to inform the Soc iety without delay of circumstan ces which may causethe date or the extent of the surveys to be ch anged.

ARTICLE 5

5.1. - The Society acts as a provider of services. This ca nnot be construed as anobligation bearing on the Society to obtain a result or in a warranty.

5.2. - The certificates issued by the Society pursuant to 5.1. here above are astatement on the level of compliance of the Unit to its Rules or to the documents ofreference for the Services provided for.

In particular, the Society does not engage in any work relating to the design,building, production or repair c hecks, neither in the operation of the Units or in theirtrade, neither in any advisory services, and ca nnot be held liable on those accounts.Its certificates cannot be construed as an implied or expr ess warranty of safety,fitness for the purpose, seaworth iness of the Unit or of its value for sale, insuranceor chartering.

5.3. - The Society does not declare the acceptance or commissioning of a Unit, thatbeing the exclusive responsib ility of its owner.

5.4. - The Services of the Society ca nnot create any obligation bearing on theSociety or constitute any warranty of proper operation, beyond any repr esentationset forth in the Rules, of any Unit, equipment or machinery, compu ter software of anysort or other comparable concepts that has been subject to any survey by theSociety.

ARTICLE 6

6.1. - The Society accepts no responsibility for the use of information related to itsServices which was not provided for the purpose by the Society or with its assistance.

6.2. - If the Services of the Society cause to the Client a damage which is proved tobe the direct and reasonably foreseeable consequence of an error or o miss ion of theSociety, its liability towards the Client is limited to ten times the am ount of fee paidfor the Service having caused the damage. This limit is subject to a mini mum of fiftythousand (50.000) French francs, and to a maximum which is the greater of fivemillions (5.000.000) French francs and one and a half times the above mentioned fee.

The Society bears no liability for indirect or consequential loss such as e.g. loss ofrevenue, loss of profit, loss of production, loss relative to other contracts andindemnities for termination of other agreements.

6.3. - All claims are to be presented to the Society in writing and on pain ofdebarment by right, within three months of the date the Services were supplied or ofthe date the events which are t aken advantage of were first known.

ARTICLE 7

7.1. - Requests for Services are to be in writing.

7.2. - Either the Client or the Society can terminate as of right the requested Servicesby prior written notice according to paragraph 7.3., for convenience, and wit houtprejudice to the provisions in Article 8 hereunder.

7.3. - The notice due by the Society to the Client to exercise the possib ility under 7.2.is of three calendar months and conversely, of ten banking days.

7.4. - The class granted to the concerned Units and the previously issued certificatesremain valid until the date of effect of the notice issued according to 7.2. hereabovesubject to compliance with 2.3. hereabove and Article 8 hereunder.

ARTICLE 8

8.1. - The Services of the Society, whether completed or not, involve the payment of feeupon receipt of the invoice and the reimbursement of the expenses incurred.

8.2. - The class of a Unit may be suspended in the event of non-payment of fee after afirst unfruitful notification to pay.

ARTICLE 9

9.1. - The documents and data provided to or prepared by the Society for its Services, andthe information available to the Society, are treated as confidential. However:• Clients have access to the data they have provided to the Society and to the reports

and certificates which have been prepared for them;• copy of the documents made available for the classification of the Unit can be

handed over to another Classification Society Member of the InternationalAssociation of Classification Societies (IACS) in case of the Unit’s transfer of class;

• the data relative to the evolution of the Register, to the class suspension and to thesurvey status of the Units are passed on to IACS according to the associationworking rules;

• technical records and history related to specific class notations may be transferred tothe new owner in case of change of ownership;

• the certificates, documents and information relative to the Units classed with theSociety are passed on upon order of the flag authorities of the Unit or of a Courthaving jurisdiction.

The documents and data are subject to a file management plan.

ARTICLE 10

10.1. - Any delay or shortcoming in the performance of its Services by the Society arisingfrom an event not reasonably foreseeable by or beyond the control of the Society shall bedeemed not to be a breach of contract.

ARTICLE 11

11.1. - The Society may designate another Surveyor at the request of the Client in case ofdiverging opinions during surveys.

11.2. - Disagreements of a technical nature between the Client and the Society can besubmitted by the Society to the advice of its Classification Committee.

ARTICLE 12

12.1. - Disputes over the Services carried out by delegation of Governments are assessedwithin the framework of the applicable agreements with the States, internationalConventions and national rules.

12.2. - Disputes arising out of the payment of the Society’s invoices by the Client aresubmitted to the Court of Nanterre, France.

12.3. - Other disputes over the present General C onditions or over the Servi ces ofthe Society are exclusively submitted to arbitration in London according to theLondon arbitration procedural r ules in force. English law applies.

ARTICLE 13

13.1. - These General C onditions constitute the sole contractual obligations bindingtogether the Society and the Client, to the exclusion of all other representation,statements, terms, conditions whether expr ess or implied. They may be varied inwriting by mutual agreement.

13.2. - The invalidity of one or more stipulations of the present General Conditions doesnot affect the validity of the remaining provisions.

13.3. - The definitions herein take precedence over any definitions serving the samepurpose which may appear in other documents issued by the Society.

November 2001

RULE NOTE NR 476

APPROVAL TESTING of WELDERS

Section 1 Approval Testing and Certification of Welders for Fusion Welding

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 8

3.1 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

NR 476, Sec 1

November 2001 Bureau Veritas 3

SECTION 1 APPROVAL TESTING AND CERTIFICATION OF

WELDERS FOR FUSION WELDING

1 General

1.1

1.1.1 This document gives approval testing conditions,acceptance requirements and range of approval of weldersemployed 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 fusionwelding processes designated as manual or semi-automaticwelding processes where the quality of the welded jointdepends mainly on the manual skill of the welder. Opera-tors using fully mechanized and fully automatic weldingprocesses are to be suitably trained and experienced.

1.1.3 After satisfactory completion of approval tests underthe supervision of a Society surveyor, the Society will issuean 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 thisdocument may be used upon special consideration of theSociety.

2 Welders employed for steel hull

2.1 Variables for approval testing

2.1.1 Welding processesManual 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 consumablesIn general approval tests are carried out using filler metal ofgrade matching the base material strength.

2.1.3 Type of weld jointA change of type of weld joint to type for which the welderis not approved shall require new approval testing.

2.1.4 Type and dimensions of base productsWelding of base products with dimensions out of theapproved range shall require new approval testing.

2.1.5 Welding positionA change in the position of welding to one for which thewelder 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 processApproval tests are to be performed for each process.

2.2.2 Welding consumablesApproval is extended to the use of any consumables similarto the type used for the approval tests and suitable for thematerials to be welded and processes used.

A change in the type of covered electrode may require achange in the welder’s technique. Approval tests performedwith a type of covered electrode may extend approval to theuse of other types of covered electrode as specified in Tab1.

Table 1 : Range of approval for electrode coating

2.2.3 Range of thicknessAccording to the thickness of approval test pieces, the rangeof approval for plate thickness is given in table 2. The limitsare not to be understood as strict conditions.

Table 2 : Approval test piece thickness and range ofapproval

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 rutile-cellulosic or rutile-thick covering

Basic covering Acid or rutile-acid covering or rutile or rutile-basic or rutile-cellulosic or rutile-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

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 filletwelds in horizontal overhead (PD), vertical upwards (PF)positions extend approval to butt and fillet productionwelding in all positions except vertical downwards. This setof tests also extends approval to production fillet welding offixed hollow sections to plate in positions PB, PF and PD asshown in Fig 4.

Approval tests performed on butt welds in horizontal (PC),vertical upwards (PF) positions and on fillet welds in verticalupwards (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 productionwelding in positions tested and type of joint welded.

2.2.5 Steel categoryBase materials for approval tests are to be of normalstrength (grades A, B, D or E) or higher strength (AH32 toFH40) hull steel grades. Approval is extended to productionwelding of all hull steel grades.

2.2.6 Backing and gouging conditionsBacking and gouging range of approval is as follows :

• Satisfactory approval test pieces welded from one sidewithout backing extend approval to welding from oneside with backing and welding from both sides with orwithout gouging.

• Satisfactory approval test pieces welded from one sidewith backing extend approval to welding from bothsides with gouging.

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

2.3 Welding of approval test pieces

2.3.1 GeneralThe welder is to have suitable practical experience and pro-fessional knowledge of the welding process including theregulation of the parameters of the welding equipment used

The surveyor may stop the test if the welding conditions arenot correct or if it appears that the welder does not have thetechnical competence to achieve the required standard.

2.3.2 Number, shape and dimensions of test piecesThe number, shape and dimensions of test pieces madewith plates are to be selected so as to cover the productionwelding 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 conditionsThe approval tests are to correspond to the conditions usedin production welding and follow a welding procedurespecification representative of production practice.

≥ 300

t

≥ 125≥ 125

t

≥ 125

t

≥ 125

≥ 150

z

a

z = a√2For t ≥ 6 mm a ≤ 0,5t

For t < 6 mm 0,5t ≤ a ≤ t

(z ~ 0,7t)~

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 arerequired;

• The test pieces are to be suitably identified with themark 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 othermethod used in production upon surveyor's agreement;

• The appearence of each pass, both for butt and filletwelds, is to be of appropriate geometry and practicallyfree 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 oneside welding without backing the root penetration of thesamples is to be regular and constant.

Figure 3 : Welding positions for plates

PB Horizontal vertical

PA Flat

PG Vertical downwards

PE Overhead

PC Horizontal

PF Vertical upwards

PA Flat

PD Horizontal overhead

PG Vertical downwardsPF Vertical upwards

a) Butt welds

b) Filled welds

NR 476, Sec 1


Figure 4 : Welding positions for hollow sections

2.4 Examinations and tests

2.4.1 GeneralThe non destructive examinations and destructive tests to beperformed are indicated in Tab 3.

Prior to mechanical tests, backing strips where used are tobe removed. The test piece can be sectioned by thermalcutting or by mechanical means discarding the first and last25mm of the test piece at the end of the plates.

Table 3 : Examinations and tests

Pipe : rotating

Axis : horizontal

Weld : horizontal vertical

PB

Pipe : fixed

Axis : horizontal

Weld : vertical upwards

PF

Pipe : fixed

Axis : vertical

Weld : horizontal overhead

PD

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.

NR 476, Sec 1


2.4.2 Test pieces and test specimensDetails 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 pieceshall be cut into several test specimens (Fig 5a). Thelength of any fracture test specimen shall be about50mm. If necessary, the weld reinforcement of the testspecimen may be removed and additionally the weldedges may be notched to a depth of about 5mm to ini-tiate fracture in the weld metal (Fig 7b). In the case ofsingle-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 2face bend test specimens shall be tested in accordancewith 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 transversebend 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 specimensshall 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

25 25Inspection length

of the test piece

� 1� 1

a) Sectioning into an even-numbered quantityof test specimens

b) Preparation

c) Fracture testing face bend test d) Fracture testing root bend test

Inspection length

of test specimen~2

~

~ 50~

~ 5~~ 5~

~2

~

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 criteriaDuring 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 byvisual and radiographic examination or fracture are to beassessed in accordance with ISO standard 5817.

The imperfections are to be within the specified limits oflevel B in ISO standard 5817 except for imperfections typeas follows : excess weld metal, excessive convexity, excessthroat thickness and excessive penetration, for which levelC is acceptable.

2.4.4 Re-testingThe test sample is to be repeated if any test piece fails tocomply with the requirements.

When the failure of the repeated test is due to the welderlack of skill, the welder is to be adequately trained and usu-ally will not be permitted to perform new approval testsunless at least a month has elapsed since the previousexamination.

2.5 Certification

2.5.1 GeneralUpon satisfactory completion of the approval tests anapproval certificate is issued stating approval tests per-formed and range of approval.

2.5.2 Initial approvalThe validity of the welder’s approval begins from the datewhen all the required tests are satisfactorily completed.

The approval shall remain valid for a period of two yearsunless the welder is not engaged in a given welding processfor which he is approved for a period exceeding six monthsand unless there is specific reason to question the welder’sability. 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-yearperiod, approval tests as per initial approval are to be per-formed. Alternative procedure may be used upon specialconsideration by the Society.

Approval tests may be reduced where records of X-ray orultrasonic inspections or test reports about fracture testsfrom production welds made by the welder are availableand maintained on file with the welder’s 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 commonlyused are listed as follows :

• Metal arc inert gas welding (MIG, ISO 4063 ref. number131)

• Tungsten inert gas welding (TIG, ISO 4063 ref. number141)

Change of welding process shall require new approval test-ing.

3.1.2 Welding consumables

Approval tests are to be carried out using suitable fillermetal and gas shield compatible with the parent metal andthe process.

3.1.3 Type of weld joint

A change of type of weld joint to type for which the welderis 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.

25

b) Fracture testing

(The fillet weld may be notched if necessary)

Inspection length

of fillet weld

a) Sectioning into an even-numbered

quantity of test specimens

25

NR 476, Sec 1


3.1.5 Welding position

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

3.2.2 Welding consumables

Approval is extended to the use of any consumables similarto the type used for the approval tests and suitable for thematerials to be welded and processes used.

3.2.3 Range of thickness

According to the thickness of approval test pieces, the rangeof approval for plate thickness is given in table 4. The limitsare not to be understood as strict conditions.

Table 4 : Approval test piece thickness and range ofapproval

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 filletwelds in horizontal overhead (PD), vertical upwards (PF)positions extend approval to butt and fillet productionwelding in all positions except vertical downwards. This setof tests also extends approval to production fillet welding offixed hollow section to plate in positions PB, PF and PD asshown in Fig 4.

Approval tests performed on butt welds in horizontal (PC),vertical upwards (PF) positions and on fillet welds in verticalupwards (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-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 conferapproval to production welds on plates and/with extrudedproducts 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 sidewith backing extend approval to welding from bothsides with gouging.

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

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 theregulation of the parameters of the welding equipment used

The surveyor may stop the test if the welding conditions arenot 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 madewith plates are to be selected so as to cover the productionwelding 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 shownin 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

≥ 300

t

≥ 150≥ 150

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 procedurespecification 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 beidentified for further examination;

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

• The test pieces are to be suitably identified with themark 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 othermethod used in production upon surveyor's agreement;

• The appearence of each pass, both for butt and filletwelds, 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 oneside welding without backing the root penetration of thesamples is to be regular and constant.

3.4 Examinations and tests

3.4.1 GeneralThe non destructive examinations and destructive tests to beperformed are indicated in Tab 5.

Prior to mechanical tests, backing strips where used are tobe removed. The test piece can be sectioned by thermalcutting or by mechanical means discarding the first and last25mm of the test piece at the end of the plates.

3.4.2 Test pieces and test specimensDetails 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 usingclass B technique;

• When fracture testing is used, the full test piece inspec-tion length shall be tested and to do this, the test pieceshall be cut into several test specimens (Fig 5a). Thelength of any fracture test specimen shall be about50mm. If necessary, the weld reinforcement of the testspecimen may be removed and additionally the weldedges may be notched to a depth of about 5mm to ini-tiate fracture in the weld metal (Fig 7b). In the case ofsingle-sided welding without backing, half of theinspection 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 2face bend test specimens shall be tested. The mandreldiameter is to be 6t for alloys 5083, 5086 and 5383, 7tfor alloys 6005A, 6061 and 6082 in temper conditionT5 or T6 and the bending angle 180°.

• For plate thickness greater than 12mm, the transversebend 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 specimensshall be taken equally spaced in the inspection length.

t

≥ 150

t

≥ 150

≥ 300

z

a

z = a√2For t ≥ 6 mm a ≤ 0,5t

For t < 6 mm 0,5t ≤ a ≤ t

(z ~ 0,7t)~

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

25 25Inspection length

of the test piece

� 1� 1

a) Sectioning into an even-numbered quantityof test specimens

b) Preparation

c) Fracture testing face bend test d) Fracture testing root bend test

Inspection length

of test specimen~2

~

~ 50~

~ 5~~ 5~

~2

~

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 byvisual and radiographic examination or fracture are to beassessed in accordance with ISO standard 10042.

The imperfections are to be within the specified limits oflevel B in ISO standard 10042 except for imperfections typeas follows : excess weld metal, excessive convexity, excessthroat 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 tocomply with the requirements.

When the failure of the repeated test is due to the welderlack of skill, the welder is to be adequately trained and usu-ally will not be permitted to perform new approval testsunless at least a month has elapsed since the previousexamination.

3.5 Certification

3.5.1 General

Upon satisfactory completion of the approval tests anapproval certificate is issued stating approval tests per-formed and range of approval.

3.5.2 Initial approval

The validity of the welder’s approval begins from the datewhen all the required tests are satisfactorily completed.

The approval shall remain valid for a period of two yearsunless the welder is not engaged in a given welding processfor which he is approved for a period exceeding six monthsand unless there is specific reason to question the welder’sability. The employer/welding supervisor is to endorse the

relevant certificate at six months interval to confirm that theconditions of validity are fulfilled.

3.5.3 Prolongation

In order to renew the certificate for another two-yearperiod, approval tests as per initial approval are to be per-formed. Alternative procedure may be used upon specialconsideration by the Society.

Approval tests may be reduced where records of X-ray orultrasonic inspections or test reports about fracture testsfrom production welds made by the welder are availableand maintained on file with the welder’s 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 testsand 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 testsperformed under the supervision of a Society surveyor anapproval 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.

25

b) Fracture testing

(The fillet weld may be notched if necessary)

Inspection length

of fillet weld

a) Sectioning into an even-numbered

quantity of test specimens

25

NR 476, Sec 1


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 examinationVisual examinationRadiography testMagnetic particle testDye penetrant testMacrography Fracture testBend testOthers

Welding variablesWelding processWelding consumable

Base material groupType of base productType of weld jointRange of thicknessWelding positions

Backing and gouging conditionOthers

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

ensayos para aprobar soldadores

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