ES-S-60 Rev 4

QATAR GENERAL PETROLEUM CORPORATION

SPECIFICATION FOR THE NON DESTRUCTIVE TESTING OF WELDS ES-S-60

27/4/99

4

DATE

REV...

Ammendments to Clauses 1.4.5; 2.1; 2.4.3 ; 2.5.1 ; 2.5.3; 2.5.4 and 5.2 DESCRIPTION

COMPILED BY

ES-S-60 - SPECIFICATION FOR THE NON DESTRUCTIVE TESTING OF WELDS

QAI/2

QA

REVIEWED BY

APPROVED Page 1 of 26

SPECIFICATION FOR THE NON DESTRUCTIVE TESTING OF WELDS

REVISIONS: All revision 4 items are marked by a vertical line in the right hand border.

Distribution list :

CONTROL COPY NUMBER 1 NUMBER 2 NUMBER 3 NUMBER 4 NUMBER 5 NUMBER 6 NUMBER 7 NUMBER 8 NUMBER 9 NUMBER 10 NUMBER 11 NUMBER 12 NUMBER 13 NUMBER 14 NUMBER 15 NUMBER 16 NUMBER 17 NUMBER 18 NUMBER 19 NUMBER 20 NUMBER 21 NUMBER 22 NUMBER 23 NUMBER 24 NUMBER 25

REF. INDICATOR OM(O) OM(M) OM(D) MC(O) MC(M) MC(D) EB ED EE EF EM FS DR GS MT MCI(O) MCI(M) MCI(D) QAC QAC/1 QAC/2 QAI/1 QAI/2 QAI/3 ENE/8

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CONTENTS 1. INTRODUCTION ..............................................................................................................................5 1.1 SCOPE .................................................................................................................................................................... 5 1.2 DEFINITIONS, LANGUAGE AND UNITS ................................................................................................................ 5 1.3 ABBREVIATIONS .................................................................................................................................................... 5 1.4 REFERENCED SPECIFICATIONS AND STANDARDS .......................................................................................... 5

1.4.1 American Petroleum Institute. .................................................................................................... 6 1.4.2 American Society for Testing and Materials. .............................................................................. 6 1.4.3American Welding Society........................................................................................................... 6 1.4.4 British Standards . ...................................................................................................................... 6 1.4.5 Other Specifications.................................................................................................................... 6

2. METHOD OF OPERATION AND PERSONNEL QUALIFICATION ..................................................7 2.1 INTRODUCTION...................................................................................................................................................... 7 2.2 QUALITY ASSURANCE .......................................................................................................................................... 7 2.3 REPORTING............................................................................................................................................................ 7 2.4 NDT PERSONNEL .................................................................................................................................................. 7

2.4.1 NDT Co-ordinator ....................................................................................................................... 7 2.4.2 NDT Supervisor .......................................................................................................................... 7 2.4.3 NDT Operatives .......................................................................................................................... 7 2.5 QUALIFICATION OF NDT PERSONNEL ................................................................................................................ 8

2.5.1 Qualifications .............................................................................................................................. 8 2.5.2 NDT Co-ordinator ....................................................................................................................... 8 2.5.3 NDT Supervisor .......................................................................................................................... 8 2.5.4 NDT Operative............................................................................................................................ 8

3. MAGNETIC PARTICLE INSPECTION..............................................................................................9 3.1 INTRODUCTION...................................................................................................................................................... 9 3.2 MPI PROCEDURE................................................................................................................................................... 9

3.2.1 Procedure - General ................................................................................................................... 9 3.2.2 Procedure - Qualification ............................................................................................................ 9 3.3 TECHNIQUE IN GENERAL ..................................................................................................................................... 9

3.3.1 Surface Preparation.................................................................................................................... 9 3.3.2 Detecting Media.......................................................................................................................... 9 3.3.3 Magnetisation ............................................................................................................................. 9 3.3.4 Flaw Indicators and Field Strength Meters ................................................................................. 10 3.3.5 Inks ............................................................................................................................................. 10 3.4 PRACTICAL PROCEDURES................................................................................................................................... 10

3.4.1 Application of External Magnetic Field........................................................................................ 10 3.4.2 Application of Detecting Media ................................................................................................... 10 3.5 REPORTING............................................................................................................................................................ 10 3.6 CHECKS ON CONSUMABLES AND EQUIPMENT................................................................................................. 10 3.7 DEMAGNETISATION .............................................................................................................................................. 11

4. LIQUID PENETRANT TESTING.......................................................................................................12 4.1 INTRODUCTION...................................................................................................................................................... 12 4.2 PENETRANT PROCEDURES ................................................................................................................................. 12 4.3 TECHNIQUES IN GENERAL................................................................................................................................... 12

4.3.1 Penetrant - Consumables ........................................................................................................... 12 4.3.2 Approved Techniques................................................................................................................. 12 4.4 REPORTING............................................................................................................................................................ 12 4.5 CLEANING............................................................................................................................................................... 13

5. ALTERNATING CURRENT FIELD MEASUREMENT (ACFM) .........................................................14 5.1 INTRODUCTION...................................................................................................................................................... 14 5.2 NDT PERSONNEL .................................................................................................................................................. 14 5.3 EQUIPMENT............................................................................................................................................................ 14

5.3.1 Topside ....................................................................................................................................... 14 5.3.2 Sub-Sea...................................................................................................................................... 14 5.3.3 Probes ........................................................................................................................................ 14 5.3.4 Operational Test Block ............................................................................................................... 14

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5.4 SURFACE PREPARATION ..................................................................................................................................... 14

5.4.1 Magnetic State............................................................................................................................ 15 5.5 PRACTICAL PROCEDURES................................................................................................................................... 15

5.5.1 General Information .................................................................................................................... 15 5.5.2 Scan Data ................................................................................................................................... 15 5.5.3 Detailed Indication Record.......................................................................................................... 15 5.6 PROBE DEPLOYMENT........................................................................................................................................... 15 5.7 TEMPERATURE ...................................................................................................................................................... 15 5.8 MATERIALS............................................................................................................................................................. 15

6. ULTRASONIC EXAMINATION.........................................................................................................17 6.1 INTRODUCTION...................................................................................................................................................... 16 6.2 NDT PERSONNEL .................................................................................................................................................. 17 6.3 EQUIPMENT............................................................................................................................................................ 17

6.3.1 Flaw Detector.............................................................................................................................. 17 6.3.2 Calibration Blocks ....................................................................................................................... 17 6.3.3 Ultrasonic Probes ....................................................................................................................... 17 6.4 PERFORMANCE MONITORING CHECKS ON ULTRASONIC EQUIPMENT......................................................... 18

6.4.1 Flaw Detector.............................................................................................................................. 18 6.4.2 Probes ........................................................................................................................................ 18 6.5 ULTRASONIC TEST PROCEDURES...................................................................................................................... 18

6.5.1 Test Procedures in General........................................................................................................ 18 6.5.2 Test Procedures - Qualification .................................................................................................. 19 6.6 PREPARATION FOR EXAMINATION ..................................................................................................................... 19 6.7 SENSITIVITY ........................................................................................................................................................... 20

6.7.1 Scanning Sensitivity.................................................................................................................... 20 6.7.2 Reference Sensitivity .................................................................................................................. 20 6.8 REFERENCE CALIBRATION BLOCK ..................................................................................................................... 20

6.8.1 Calibration Block ......................................................................................................................... 20 6.9 SCANNING PATTERN ............................................................................................................................................ 20 6.10 DISCONTINUITY LOCATION ................................................................................................................................ 20 6.11 FLAW SIZE EVALUATION .................................................................................................................................... 20 6.12 DEFECT ACCEPTANCE LEVELS......................................................................................................................... 20 6.13 REPORTING OF FLAWS ...................................................................................................................................... 20 6.14 REPORT FORMAT ................................................................................................................................................ 21

7. X RAY AND GAMMA RADIOGRAPHY ............................................................................................22 7.1 INTRODUCTION...................................................................................................................................................... 22 7.2 RADIOGRAPHIC PROCEDURE ............................................................................................................................. 22

7.2.1 Procedure - General ................................................................................................................... 22 7.2.2 Procedure Sheets ....................................................................................................................... 22 7.2.3 Qualification of Radiographic Procedure .................................................................................... 23 7.3 TECHNIQUE IN GENERAL ..................................................................................................................................... 23

7.3.1 Sources and Techniques ............................................................................................................ 23 7.3.2 Screens....................................................................................................................................... 23 7.3.3 Films ........................................................................................................................................... 23 7.3.4 Film Identification........................................................................................................................ 24 7.3.5 Image Quality Indicators (IQI)..................................................................................................... 24 7.3.6Exposure Geometry..................................................................................................................... 24 7.3.7 Focus to Film Distance ............................................................................................................... 24 7.3.8 Film Density ................................................................................................................................ 24 7.3.9 Film Overlap ............................................................................................................................... 24 7.4 FILM PROCESSING ................................................................................................................................................ 24 7.5 FILM STORAGE ...................................................................................................................................................... 25 7.6 INTERPRETATION AND REPORTING ................................................................................................................... 25

TABLE 1 - REFERENCE BLOCK THICKNESS...................................................................... 26

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1. INTRODUCTION 1.1 SCOPE This specification defines the requirements for conducting non destructive testing of welds and materials in structural steelwork, pipelines, process piping, pressure vessels, etc., for QGPC Installations in the Arabian Gulf. 1.2 DEFINITIONS, LANGUAGE AND UNITS The following definitions apply throughout this specification: EMPLOYER

Shall mean QATAR GENERAL PETROLEUM CORPORATION (QGPC) or appointed MANAGING CONSULTANT

CONTRACTOR

The party which entered into contract with the EMPLOYER for the execution of activities as mentioned in a written agreement.

The following use of language applies throughout this specification: i)

'shall' is used where a provision is mandatory,

ii)

'should' is used where a provision is preferred,

iii)

'may' is used where alternatives are equally acceptable.

The term 'approve' as applied to the EMPLOYER is used where the EMPLOYER does not wish work to proceed unless certain features have been agreed in writing with the CONTRACTOR. This does not mean that all the details of a document have been considered by the EMPLOYER and does not absolve the CONTRACTOR of his responsibilities. All communication both documentary and spoken shall be in the English Language and all dimensions and weights shall be in SI (Systeme International d' Unites) units. 1.3 ABBREVIATIONS The following abbreviations are used throughout this specification: API

American Petroleum Institute

ACFM

Alternating Current Field Measurement

ANSI

American National Standards Institute

ASNT

American Society for Non-Destructive Testing

ASTM

American Society for Testing and Materials

BS

British Standard

DAC

Distance Amplitude Correction

IQI

Image Quality Indicator

LPI

Liquid Penetrant Inspection

MPI

Magnetic Particle Inspection

NDT

Non-Destructive Testing

PCN

Personnel Certification in Non Destructive Testing

QA

Quality Assurance

QC

Quality Control

RT

Radiographic Testing

UT

Ultrasonic Testing

1.4 REFERENCED SPECIFICATIONS AND STANDARDS The following standards are referenced in this specification. A reference in this specification to these documents involves the latest published issue together with any amendments. Document No.

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1.4.1 American Petroleum Institute. API RP 2X

Ultrasonic Examination of Offshore Structural Fabrication and Guidelines for Qualification of Ultrasonic Technicians.

1.4.2 American Society for Testing and Materials. ASTM A435

Straight Beam Ultrasonic Examination of Steel Plates.

ASTM E94

Standard Recommended Practice for Radiographic Testing.

ASTM E142

Standard Method for Controlling Quality of Radiographic Testing.

ASTM E165

Standard Practice for Liquid Penetrant Inspection Method.

ASTM E709

Standard Practice for Magnetic Particle Examination.

ASTM E747

Controlling Quality of Radiographic Testing Using Wire Penetrameters.

ASTM E1032

Radiographic Examination of Weldments.

1.4.3 American Welding Society AWS A2.4

Symbols for Welding and Non Destructive Testing.

1.4.4 British Standards . BS 2704

Specification for Calibration Blocks for use in Ultrasonic Flaw Detection.

BS 3683

Glossary of Terms used in Non Destructive Testing.

BS 4069

Specification for Magnetic Flaw Detection Inks and Powders.

BS 4331

Guidance on the In-Service Monitoring of Probes (excluding immersion probes)

BS 4489

Method for Measurement of UV-A Radiation (black light) used in NDT.

BS 6072

Method for Magnetic Particle Flaw Detection.

BS EN 462-1 BS EN 571-1 BS EN 1435 BS EN 1714 BS EN 1060 1.4.5 Other Specifications. ASNT-TC-1A

Personnel Qualification and Certification in Non Destructive Testing.

PCN/GEN/97 App E2 Iss 32

Requirements for PCN Certification of Personnel engaged in Liquid Penetrant inspection.

PCN/GEN/927 App E1 Iss 3

Requirements for PCN Certification of Personnel engaged in Magnetic Particle Inspection.

PCN/GEN/W/97 RT1App C2 (Alt) Iss 390

Specific requirements for PCN Certification of Personnel engaged in the Radiographic Testing of Welds.

PCN/GEN/97W/UT1 App C1 Iss 3.90

Specific requirements for PCN Certification of Personnel engaged in the Ultrasonic Testing of Fusion Welded Ferritic Steels.

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2. METHOD OF OPERATION AND PERSONNEL QUALIFICATION 2.1 INTRODUCTION This section of the specification defines the requirements for conducting non destructive testing of welds & materials and the minimum qualification requirements for CONTRACTOR NDT personnel engaged in ultrasonic, radiographic, magnetic particle, liquid penetrant testing and ACFM where applicable.. 2.2 QUALITY ASSURANCE Before the commencement of work on the contract, the CONTRACTOR shall submit the following documentation for approval by the EMPLOYER: a)

An organigram which defines the role of the CONTRACTOR's staff responsible for NDT.

b)

An internal quality manual relating to NDT operations.

c)

Written NDT procedures, including procedure qualification tests.

d)

A list of NDT operatives and supervisory staff, supported by relevant certification and supplementary evidence.

e)

A list of equipment to be used under the contract.

The effectiveness of the quality system and quality plan used by the CONTRACTOR will be subject to monitoring by the EMPLOYER and in addition may be audited following an agreed period of notice. 2.3 REPORTING The CONTRACTOR shall be responsible for the accuracy and the validity of all NDT reports submitted to the EMPLOYER. Site NDT reports produced during the contract shall be collated, processed by the CONTRACTOR and used to produce a post contract report. The style and the format of the post contract report shall be subject to approval by the EMPLOYER. 2.4 NDT PERSONNEL Personnel offered for work on the EMPLOYER contracts shall fully comply with the requirements given in Clause 2.5. Authenticated copies of original certification of all personnel shall be submitted to the EMPLOYER for approval prior to the commencement of operations. Verification of claims of experience shall be by copies of log books, references and certificates which shall be submitted by the CONTRACTOR. Details of NDT training and performance shall be available for EMPLOYER scrutiny to confirm adequate job experience. 2.4.1 NDT Co-ordinator The CONTRACTOR shall employ an NDT co-ordinator who will liaise with the EMPLOYER on all operational and technical matters related to NDT. The responsibilities of the NDT co-ordinator are as follows:a)

Submission of necessary documents.

b)

Specification and running of procedure qualification tests.

c)

Control of all NDT activities.

d)

Data collection and reporting.

2.4.2 NDT Supervisor Supervision of all NDT operatives on sites shall be carried out by NDT supervisors, who may also be the NDT co-ordinator described in Clause 2.4.1. Their function is to:a)

Endorse all NDT reports issued by the NDT operatives.

b)

Ensure and witness that the mandatory checks on NDT equipment and consumables is carried out and reported in accordance with EMPLOYER specifications.

c)

Ensure that the examination coverage satisfies the requirements defined in the specifications.

2.4.3 NDT Operatives The EMPLOYER will assess the suitability of any NDT operatives prior to his being accepted for contract duties. AAt the discretion of the EMPLOYER’S sponsoring department this assessment shall be carried out in the form of a trade test. The ttests shall be conducted by the EMPLOYER or an

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independent inspection agency approved by the EMPLOYERY. The EMPLOYER may audit the performance of all NDT personnel as necessary and instruct the CONTRACTOR that he ceases to use personnel whose performance is considered unsatisfactory. 2.5 QUALIFICATION OF NDT PERSONNEL 2.5.1 Qualifications Either of the following qualifications shall be accepted by the EMPLOYER: a)

CSWIP/PCN Level II with a minimum of 2 years post qualifying experience.

b)

ASNT recommended practice SNT-TC-1A to Level II proficiency with a minimum of 2 years post qualifying experience.

NNo consideration shall be given to any other qualifications without the EMPLOYER’s approval. NNDT operatives qualified in accordance with ASNT recommended practice SNT-TC-1A Level II shall be ccertified, prior to his being acceptable for contract duties, by an ASNT Level III certifiedqualified pperson acceptable toapproved by the EMPLOYER. The EMPLOYER at its discretion may seek independent certification iif operational circumstances dictate. All personnel shall be required to furnish proof of having been examined in the preceding 12 months by a competent medical authority to prove a natural or corrected near vision acuity for reading J-1 letters on Jaegers Standard Test Chart at a distance of not less than 300mm, a natural or corrected distance acuity of not less than 20/40 and colour blindness to ISHIHARA for all NDT techniques iin this specification. 2.5.2 NDT Co-ordinator The NDT co-ordinator shall have ultrasonic or radiographic qualifications conforming to the requirements of Clause 2.5.1. When the NDT co-ordinator takes on the function of the NDT supervisor, the minimum qualification requirements shall be as that of the NDT supervisor. 2.5.3 NDT Supervisor The NDT supervisor shall have full ultrasonic, radiographic, magnetic particle, and liquid penetrant and ACFM qualifications, applicable to the scope of work given within the schemes given in Clause 2.5.1; plus at least 5 years site experience since qualifying. NDT supervisors shall have a thorough knowledge of the CONTRACTOR's Quality Assurance Documentation. 2.5.4 NDT Operative The NDT operative shall have relevant qualifications in accordance with Clause 2.5.1. Further requirements for approval of ACFM and ultrasonic operatives are specified in Clauses 5.2 and 6.2 respectively.

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3. MAGNETIC PARTICLE INSPECTION 3.1 INTRODUCTION This section covers the site inspection of plate, pipe and structural weld connections by wet and dry magnetic particle inspection (MPI) methods. The techniques and procedures used shall be in accordance with BS 6072 or ASTM E709 except as modified herein. 3.2 MPI PROCEDURE 3.2.1 Procedure - General A written procedure shall be submitted to the EMPLOYER for approval, and shall include the following information: a)

Surface preparation.

b)

Magnetic ink and method of application.

c)

Means of external magnetisation and the equipment used.

d)

Means of ensuring the adequacy of the magnetic flux density.

e)

Consumables and equipment tests and their frequency.

f)

Technique sketch indicating the direction, coverage of the applied magnetisation and the probing pattern.

g)

Reporting format.

h)

Acceptance levels.

i)

Operator qualifications.

3.2.2 Procedure - Qualification The approved procedure shall be qualified by the CONTRACTOR in the presence of the EMPLOYER. The following techniques, when employed, shall be qualified on sample pieces of relevant geometry: a)

Any technique to be used for examination of variable geometry welds.

b)

Flexible cable or coil techniques.

c)

Permanent Magnet.

d)

Electromagnet (AC/DC Yoke).

e)

Fluorescent ink technique.

The qualification tests shall demonstrate:a)

Satisfactory surface preparation including the application of contrast coating.

b)

Provision of an adequate magnetisation level and direction, see Clause 3.4.1.

If required by the EMPLOYER, the CONTRACTOR shall provide test pieces containing weld flaws so as to demonstrate the sensitivity of the technique. 3.3 TECHNIQUE IN GENERAL 3.3.1 Surface Preparation The tested surface shall be free from grease, oil, scale, rust, flux, spatter and any form of protective coating. If necessary the surfaces shall be dressed out with a light grinding so that the surface roughness or irregularities present do not interfere with the interpretation. The grinding direction shall not coincide with the expected orientation of the flaws. Proprietary contrast coats shall be used to enhance the area under inspection. The coating shall tightly adhere to the surface, forming a thin and coherent film. 3.3.2 Detecting Media Magnetic and fluorescent inks shall comply with the requirements of BS 4069 or ASTM E709. 3.3.3 Magnetisation The preferred techniques for applying the external magnetic field are: a)

A.C. yoke with adjustable pole pieces.

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b)

Flexible cable or coil carrying a.c. or d.c.

The use of permanent magnet yokes shall require the approval of the EMPLOYER. A.C. prods shall not be used. 3.3.4 Flaw Indicators and Field Strength Meters Burma-Castrol type II flaw indicators (or other type approved by the EMPLOYER), and portable field strength meters shall be used on each length of weld examined. Before fillets or variable geometry welds are examined, two flaw indicators orientated at right angles to each other shall be attached flat onto the vertical plate surface as near to the weld as possible. When magnetised and sprayed with ink all three lines on each flaw indicator shall be clearly visible. 3.3.5 Inks All MPI shall be conducted using wet inks. The use of fluorescent inks is allowed in those work areas which can be shaded so as to reduce the ambient light level to below 10 lux. The use of dry powder techniques shall only be permitted for hot checks with the approval of the EMPLOYER. 3.4 PRACTICAL PROCEDURES 3.4.1 Application of External Magnetic Field The direction of magnetisation shall be such as to detect both longitudinal and transverse orientated weld flaws. The maximum pole spacing of the yoke shall not exceed 170mm. The area of magnetic coverage of a yoke is considered to be a circle inscribed between the pole pieces, except that the zone adjacent to the poles having a width of 15mm shall not be evaluated. The degree of overlap of successive areas during examination shall be 25% minimum. 3.4.2 Application of Detecting Media The magnetic media shall be applied during continuous magnetisation of the part. Inspection shall be carried out whilst the magnetic field is present. Excess magnetic particles may be removed by blowing of the area under inspection. 3.5 REPORTING All indications shall be assessed in accordance with the acceptance levels given in the appropriate QGPC application specification. Indications which are not permitted shall be reported and may be further investigated either by repeating the test or by light dressing (not exceeding a depth of 1mm) followed by an MPI retest. If the retest shows that the indication still remains outside the code requirements, any subsequent surface treatment shall be classed as a weld repair. The results of MPI shall be recorded and the report shall contain at least the following information: a)

Date and time of inspection

b)

Name of Inspection Company.

c)

Identification of the workpiece.

d)

State if edge or weld; for the latter, the welding process and stage of inspection.

e)

Surface conditions.

f)

Technique number and essential parameters.

g)

The commercial name of the examination medium and the identification number of the magnetising medium.

h)

Inspectors name and signature.

i)

Level of inspectors qualification.

j)

The test results.

3.6 CHECKS ON CONSUMABLES AND EQUIPMENT Where magnetic inks are prepared on site, their concentration shall be tested at a minimum of once per day and the containers shall be appropriately marked to record the test.

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Variable current transformers shall be checked at agreed intervals and the results recorded. The intensity and wavelength of black light at the surface shall be in accordance with BS 4489 or ASTM E709. These shall be tested at intervals agreed by the EMPLOYER and the results of the test recorded. At the beginning of each shift the lifting power of the electromagnetic yokes shall be tested and the results of the test recorded in the calibration log. The lifting power shall exceed 4.5 Kg for the maximum pole spacing. For permanent magnets the lifting power shall exceed 18Kg for the maximum pole spacing, if this is greater than 75mm or 0.24Kg per millimetre of pole spacing , if this is less than 75mm. 3.7 DEMAGNETISATION If the component to be tested exhibits residual magnetism then demagnetisation shall be carried out in accordance with Clause 22 of BS 6072 or ASTM E709.

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4. LIQUID PENETRANT TESTING 4.1 INTRODUCTION This section of the specification covers the inspection of welded and brazed joints by Liquid Penetrant Inspection (LPI) methods. The techniques and procedures used shall be in accordance with BS 6443 or ASTM E165, except as where modified herein. 4.2 PENETRANT PROCEDURES A written procedure shall be submitted to the EMPLOYER for approval and shall include the following information: a)

Penetrant inspection materials.

b)

Application range of the procedure.

c)

Surface preparation.

e.g., the pre-cleaning method, cleaning agent, allowable range of controllable parameters (i.e. temperature range, surface roughness) d)

Application of penetrant.

e.g., the method of application, range of permissible contact times, range of permissible temperatures for the component and the penetrant. e)

Removal of penetrant.

e.g., the cleaning agent and method of application, range of permissible temperatures for the component, criteria that define the completion of the operation. f)

Developing:-

e.g., the developer used, method of application, range of permissible development times. g)

Control tests of penetrant inspection materials.

h)

Reporting format.

i)

Operator qualifications

If required by the EMPLOYER , the procedure shall be qualified on relevant test pieces. 4.3 TECHNIQUES IN GENERAL 4.3.1 Penetrant - Consumables All LPI materials, including cleaning agents, shall be of the same manufacture and belong to the same group. The halogen content of consumables shall be limited to 1%, except that for examination of austenitic stainless steels, halogen free materials, as certified by the penetrant manufacturer, shall be used. 4.3.2 Approved Techniques LPI shall be carried out by either the visible or the fluorescent solvent removable penetrant techniques, o used in the temperature range 15 - 60 C , or within the temperature range specified by the manufacturer. Any deviation shall require the approval of the EMPLOYER. 4.4 REPORTING All indications shall be assessed in accordance with the acceptance levels given in the referencing code. Rejectable indications shall be reported. A retest is permitted, provided that no additional surface preparation to that specified in the original test procedure is to be applied. The indications shall not be dressed out by grinding or other abrasive method without the approval of the EMPLOYER. The results of LPI shall be recorded and the report shall contain at least the following information: a)

Date and time of inspection

b)

Name of Inspection Company.

c)

Identification of the workpiece.

d)

State if edge or weld; for the latter, the welding process and stage of inspection.

e)

Surface conditions.

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f)

Technique number and essential parameters.

g)

The commercial name of the examination medium.

h)

Inspectors name and signature.

i)

Level of inspectors qualification.

j)

The test results.

4.5 CLEANING Upon completion of the examination, all tested parts shall be thoroughly cleaned to remove all traces of the Penetrant inspection material.

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5. ALTERNATING CURRENT FIELD MEASUREMENT (ACFM) 5.1 INTRODUCTION This section highlights the procedural requirements for the use of Alternating Current Field Measurement (ACFM) for the Non Destructive Testing of welds. ACFM can be used for detection and sizing (length & depth) of surface breaking cracks in metal structures, components or welds. As a detection tool ACFM can be considered as a replacement for MPI. 5.2 NDT PERSONNEL Experienced topside operator with a pass certificate from one of the following approved courses: 1. Lloyds Register approved training course for topside operators for the inspection of tubular joints. 2. CSWIP (ACFM) 3. PCN/GEN/97 App C3B. For sub-sea operations the diver is not required to be ACFM qualified. The diver should hold CSWIP 3.1U and must be briefed by the ACFM operator on probe handling and scanning procedure. For two man topside operation (e.g. rope access), the probe handler should ideally be experienced in general NDT but is not required to be ACFM qualified. The ACFM operator must brief the probe handler on probe handling and scanning procedures. 5.3 EQUIPMENT ACFM is proprietary equipment of TSC Ltd, Milton Keynes, UK. Several models exist, however the most relevant for general NDT purposes in QGPC are as follows: 5.3.1 Topside The Crack Microguage Model U9b is the latest version of the portable unit. This unit can be battery or mains operated. The software QFM version 2.2 should be used with this instrument. This instrument can be used in ACFM and ACPD modes. The U9a together with QFMv1.1 is also capable of performing ACFM and ACPD measurements. 5.3.2 Sub-Sea The ACFM Crack Microguage Model U21R is the latest version of the subsea model. This version has been ruggedised to withstand harsh local conditions. The unit should be used with WAMI version 4.4 or later. The standard U21R is ACFM only. The predecessor to the U21, the U11 is capable of performing ACFM and ACPD measurements. The software packages WAMIv3.8 (ACFM) and QPDv1.1 (ACPD) should be used. 5.3.3 Probes All ACFM / ACPD probes should be approved by manufacturer. 5.3.4 Operational Test Block ACFM does not require calibration. However the contractor should verify correct system operation using an operational test block. This usually consists of a flat welded plate with semi-elliptical EDM slots of 50x5mm and 20x2mm. 5.4 SURFACE PREPARATION The use of ACFM does not require the removal of coatings prior to inspection. This includes coatings several mm thick. However smooth probe travel over the surface is required. Anything likely to interfere with probe travel should be removed. This included loose paint and rust. For subsea applications the removal of hard marine growth is required. This can usually be achieved using a high pressure water jet. It is NOT necessary to clean to bright shiny metal. Document No.

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5.4.1 Magnetic State It must be ensured that the surface being inspected is in an unmagnetised state. Remnant magnetisation (e.g. from previous MPI inspection) can produce signals that may be mistaken for defect signals. Therefore the procedure for any previous magnetic technique must include demagnetisation of the surface. 5.5 PRACTICAL PROCEDURES It is essential that a detailed written record be maintained for all ACFM inspection. Failure to do so will severely limit the usefulness of the electronically stored ACFM scans and will render off-line interpretation difficult. Each data sheet should include the following information 5.5.1 General Information Date Operators Name Probe Operator’s Name Component ID Probe ID Probe File 5.5.2 Scan Data Filename Page Number (WAMI / QFM) Position on Weld (e.g. Brace toe, Chord toe, Weld Cap) Scan direction (A or C) Clock or tape positions Inspection Summary 5.5.3 Detailed Indication Record Filename Page number Position on Weld Start of Defect (Tape reference) End of Defect (Tape reference) Length of Defect (mm) Depth of Defect (mm) Remarks Sketch of Geometry 5.6 PROBE DEPLOYMENT A standard weld probe has a scan width of approximately 20mm. The recommended scan speed is 10 to 20mm/sec. Where the weld cap is greater than 20mm multiple passes should be made. ACFM requires that the probe be scanned along a line parallel to the defect. Defects that lie at an angle greater than approximately 25º to the weld may not be detected. In general defects are constrained to a weld toe and this does not represent a problem. However if transverse cracking is suspected then procedures for the detection of transverse cracking have been developed and should be adopted. 5.7 TEMPERATURE ACFM is routinely used on live plant at elevated temperatures. Special probes are available for operation at temperatures in excess of 500ºC. 5.8 MATERIALS ACFM can be used on magnetic and non-magnetic materials. When used on non-magnetic materials, defect detection and signal interpretation is similar to that for magnetic materials although the display scaling may need to be adjusted. The ACFM defect sizing routines only apply to carbon steels and the use of ACFM to size defects in

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non-magnetic material requires some calibration to be conducted. The equipment manufacturers are able to offer advice on these aspects.

6. ULTRASONIC EXAMINATION 6.1 INTRODUCTION This section of the specification covers manual ultrasonic examination (UT) of full penetration butt welds, structural joints and tubular intersections in thicknesses of 6mm and greater.

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The ultrasonic techniques used shall be in accordance with this specification and the appropriate construction/fabrication specification. 6.2 NDT PERSONNEL All ultrasonic operatives shall be qualified in the relevant test category as stated below (for ASNT Qualified Personnel this shall be in addition to their qualification) :a)

Plate.

b)

Butt weld (including longitudinal and girth weld seams in tubulars 610mm diameter and above).

c)

Pipe welds.

d)

Structural T-welds

e)

Nozzle welds.

f)

Tubular intersections.

They will be required to produce evidence of relevant site experience of at least 6 months in the 12 months preceding the date of the assignment. 6.3 EQUIPMENT 6.3.1 Flaw Detector The A-scan flaw detector shall comply with the requirements of BS 4331 : Part 1 or ASME V, Article 4, Section T- 431. 6.3.2 Calibration Blocks The following test blocks shall be used by the operatives during the test:A2 Block (either type)

)

A4 Block

)

A5 Block

)

A7 Block

)

to BS 2704

to BS 2704

Reference Block (see Clause 6.8) 6.3.3 Ultrasonic Probes All probes shall be marked with a unique probe identification number. The following data shall be recorded for each probe on a separate probe sheet:a)

Date of issue.

b)

Probe manufacturer.

c)

Nominal beam angle.

d)

Nominal frequency.

e)

Toe-in angle (twin crystal probes).

f)

Size and shape of crystal.

g)

Vertical plane beam profile along the 20dB lines.

h)

Results and dates of mandatory probe checks (see Clause 6.4.2).

All ultrasonic probes shall meet the following requirements:6.3.3.1 Resolution All compression and shear wave probes shall have been checked and certified capable of resolving the smallest step in the resolution block A7 in accordance with BS 3923:Part 1. The steps are said to be resolved when the echoes from the two radii are clearly separated at half maximum echo height or below. Document No.

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6.3.3.2 Overall Gain All compression wave probes shall have been checked and certified to have at least 50dB of gain remaining with the first echo from the 25mm dimension of the A2 block set to half screen height. All shear wave probes shall have been checked and certified to have at least 50dB of gain remaining with the first echo from the 100mm radius of the A2 block set to half screen height. 6.3.3.3 Probe Internal Echoes All probes shall have been checked as follows: Compression Wave Probes At testing ranges above 15mm for twin probes and 30mm for single probes the gain required to bring the internal probe echoes to 10mm in height shall exceed the setting obtained under Clause 6.3.3.2 by at least 40dB. Shear Wave Probes At testing ranges above 5mm for twin probes and 30mm for single probes the gain required to bring the internal probe echoes to 10mm in height shall exceed the setting obtained under Clause 6.3.3.2 by at least 40dB. 6.4 PERFORMANCE MONITORING CHECKS ON ULTRASONIC EQUIPMENT 6.4.1 Flaw Detector The following equipment checks shall be carried out at the intervals specified:a)

Time base calibration at every change of probes, change of location, after each switching on of the instrument.

b)

Time base linearity and amplifier gain (BS 4331:Part 1) to be checked after 24 hours of operation or once in a working week, whichever is the shorter period.

6.4.2 Probes The results and dates of the probe performance tests specified below shall be recorded:a)

Every working shift or every 8 hours of operation, whichever is shorter: •

probe index (+ 1mm),

•

beam angle (+ 2.0 change),

•

beam width in vertical plane (+ 2mm),

•

beam alignment (squint) (within 5 ),

o

o

(tests (i) - (iv) carried out to BS 4331 : Part 1). b)

c)

Every working shift: •

resolution,

•

overall gain,

•

reverberation.

Complete beam profile (BS 4331:Part 3) shall be checked and redrawn at least once in a working week or whenever a significant change of index, beam angle, squint or width indicates that it may be required.

Note that all tests shall be carried out with the noise suppression circuitry switched off. 6.5 ULTRASONIC TEST PROCEDURES 6.5.1 Test Procedures in General Written test procedures, which shall be subject to approval by the EMPLOYER, shall be in accordance with the requirements of this specification and contain a statement to this effect. They shall be devised to detect the defects specified by the agreed acceptance criteria, and shall be qualified on test specimens of relevant geometry in accordance with Clause 6.5.2. The following information shall be included in the test procedures:Document No.

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a)

List of equipment to be used.

b)

Details of surface preparation and ultrasonic couplant to be used.

c)

Individual and numbered technique sheets for each technique specified. The selection of techniques provided shall be sufficient to cover the examination of all types of welded joints which are to be covered under the scope of the procedure. The following information shall be given:•

Parent material and weld material designation

•

Material thickness and curvature (range)

•

Weld configuration and edge preparation

•

Welding process

•

Type of probes to be used

•

Sketch showing the joint configuration, beam coverage, accessible external surfaces from where the scan shall be conducted, extent of probe scan and examination coverage.

d)

Means of setting up the reference and scanning sensitivity levels, including measurement of transfer correction and the distance amplitude curve.

e)

Means of weld marking and fit-up checks for root face location.

f)

Scanning patterns to be used.

g)

Means of discontinuity location (taking into account the effect of curvature).

h)

Flaw reporting levels.

i)

Flaw acceptance levels (referencing code).

j)

Format of the test report.

6.5.2 Test Procedures - Qualification The requirement to qualify ultrasonic test procedures applies for the examination of: a)

Variable geometry welds such as tubular intersection welds and branch to pipe connections.

b)

Partial penetration welds and fillet welds.

c)

All closing welds.

d)

Transitional welds of unequal thickness.

e)

Longitudinal and circumferential welds in tubulars where the thickness to diameter ratio exceeds 0.03

When required the CONTRACTOR shall submit details of test pieces of relevant geometry and dimensions. The welds shall contain artificial and natural defects relevant to the type and position of the welding. The qualification tests, which will be witnessed by the EMPLOYER, shall demonstrate that:a)

The specified weld coverage can be achieved by the techniques proposed in the procedure.

b)

All reportable defects can be found at the specified sensitivity.

c)

The flaws can be classified and dimensioned to decide their acceptance or rejection in accordance with the acceptance criteria.

6.6 PREPARATION FOR EXAMINATION The ultrasonic operative shall make himself thoroughly familiar with the weld edge preparation geometry by reference to the specification and the construction/erection/fabrication and isometric drawings. Prior to ultrasonic weld examination, the operative shall carry out visual inspection of the weld in so far as to detect and note any surface and weld imperfections which would interfere with a meaningful ultrasonic examination. He shall clearly record any individual areas not covered due to scan limitations, indicating whether the obstruction is temporary or permanent. In order to facilitate weld root location in critical T, K and Y connections and single sided closure welds in tubular braces, the member from which the scanning is to be performed shall, prior to the welding of the

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root pass, be scribed at a specific surface distance from the root face under the supervision of the EMPLOYER. Joints requiring this reference marking will be identified by the EMPLOYER. 6.7 SENSITIVITY 6.7.1 Scanning Sensitivity The sensitivity used for the parent material scanning shall be the primary reference sensitivity plus 6dB. 6.7.2 Reference Sensitivity 6.7.2.1 Buried Indications The reference reflector shall be a 1.6mm diameter side drilled hole at least 22mm long in a calibration block which corresponds to the specified thickness range. A distance-amplitude correction curve (DAC) shall be prepared, to cover the beam path lengths between the minimum and maximum range to be used in the test. The thickness of the block and the position of the holes shall be as stipulated in Clause 6.8.1. A correction in instrument sensitivity is required to compensate for differences between reference standard surface roughness, contact area and acoustical attenuation characteristics. 6.7.2.2 Surface Breaking or Near Surface Defects The reference reflectors shall be API RP 2X V-notches at least 22mm long. 6.8 REFERENCE CALIBRATION BLOCK 6.8.1 Calibration Block Where examination involves beam path trajectory along the curved cross section of the tested part, the reference block should represent the curvature of the tested part if either the diameter is smaller than 500mm or the thickness to diameter ratio exceeds 0.03. A single curved reference block may be used to examine parts whose curvature is between 0.9 and 1.5 times the reference block curvature. The thickness of the reference block shall be the same as that of the tested part, or as specified in Table 1. 6.9 SCANNING PATTERN Scanning patterns shall include a separate examination of weld root. Welds shall be examined for both longitudinally and transversely orientated flaws. Submerged arc weld metal shall be examined for o transverse (chevron) cracking using a 45 probe positioned on the cap. The speed of probe movement shall not exceed 100mm/sec. 6.10 DISCONTINUITY LOCATION Where appropriate, an allowance shall be made for the effect of curvature on beam angle and sound path distance. 6.11 FLAW SIZE EVALUATION Flaw size assessment shall be based upon beam boundary intercept methods (6dB and 20dB drops), and maximum amplitude technique, as necessary. Generally the 6dB technique shall be used for measurement of defect length. 6.12 DEFECT ACCEPTANCE LEVELS Defect acceptance criteria shall be in accordance with the referencing code, except that no cracks or planar defects, such as lack of fusion or lack of penetration are allowed. 6.13 REPORTING OF FLAWS All discontinuity echoes equal to or greater than the 50% reference level shall be located, sized for length, through thickness dimension (if 3mm or greater) and recorded, giving their maximum amplitude as a percentage of the reference level. Reportable flaws shall be classed as follows:a)

Cracks,

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b)

Inclusions,

c)

Porosity,

d)

Planar indications.

If a flaw is found to exceed either the reportable or rejectable acceptance criteria specified, additional information shall be provided to identify all responses from all surfaces used to assess the defect. When a transverse indication is found in submerged arc weld metal it shall be recorded irrespective of signal amplitude and a second examination shall be performed by the NDT supervisor. 6.14 REPORT FORMAT The amount of information given on a test report shall be sufficient to reproduce the test conditions and all the relevant test parameters of the original examination. The information provided shall include:a)

Weld and welder identification,

b)

Type of weld, weld preparation and joint geometry,

c)

Material thickness,

d)

Technique and procedure number,

e)

Referencing code for acceptance criteria,

f)

Type of ultrasonic probes and their identification number,

g)

Effective probe angles on curved surfaces,

h)

Type of flaw detector and couplant used,

i)

Time base setting for each probe,

j)

Scanning sensitivity, including transfer correction,

k)

Calibration block used,

l)

Any restrictions or departures from the approved procedure,

m)

Sketch of the weld showing the position and dimensions of all reportable flaws,

n)

Amplitude of reportable indications for each probe used in the examination.

o)

Results of examination.

Prior to being submitted to the EMPLOYER, the ultrasonic reports shall be checked and endorsed by the NDT supervisor.

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7. X RAY AND GAMMA RADIOGRAPHY 7.1 INTRODUCTION The EMPLOYER will approve the safe working procedures established for the transport, storage and use of radioisotopes. Copies of certificates of authorisation relevant to the use of radioisotopes shall be provided by the CONTRACTOR. This section of the specification covers RT of structural piping, vessel, pipeline butt welds in the thickness range 5 - 50mm. The radiographic techniques used shall be in accordance with BS 2600:Part 1, BS 2910 or ASTM E1032 for structural members, except as modified herein . 7.2 RADIOGRAPHIC PROCEDURE An RT procedure containing the information required in Clauses 7.2.1 and 7.2.2 shall be submitted to the EMPLOYER for approval, after which the procedure shall be qualified by submitting radiographs produced by such a procedure for EMPLOYER approval. The details of each qualified radiographic procedure shall include the complete results of tests and radiographs qualifying the procedure in accordance with Clause 7.2.3. 7.2.1 Procedure - General The general part of the procedure shall include the following information:a)

Scope.

b)

Equipment.

c)

Density and sensitivity.

d)

Intensifying screens.

e)

Masks and filters.

f)

Film type and format.

g)

Type of penetrameter (IQI) and their placing.

h)

Limit of film coverage and film overlap.

i)

Processing and viewing conditions.

j)

Reference code and defect acceptance criteria.

k)

Operator qualifications.

l)

Format of radiographic report and marking of radiographs.

7.2.2 Procedure Sheets The detailed part of the procedure shall consist of a number of procedure sheets covering the range of diameters and thicknesses to be examined. Each procedure sheet shall cover only one group of the essential parameters shown below; a change in any of these will require a new procedure sheet. The essential parameters are:a)

Type of radiation source (X-ray or type of gamma source).

b)

Type of film (grade and type of cassette used).

c)

Intensifying screen thickness and material.

d)

Film shielding and beam collimation.

e)

Source dimensions or focal spot size.

f)

Tube voltage or type, minimum isotope activity and the corresponding minimum exposure time for the top of the thickness range.

g)

Exposure geometry.

h)

Number of exposures per completed weld or maximum length radiographed.

i)

Number of penetrameters per film or exposure.

j)

Material type (carbon steel, low alloy steel, stainless steel, cupro-nickel, etc..).

k)

Material thickness

l)

Maximum focal spot size.

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m)

Minimum film to source distance.

n)

Maximum calculated geometrical unsharpness.

o)

Typical range of exposure times for any X-ray source.

7.2.3 Qualification of Radiographic Procedure Each RT procedure shall be qualified by radiographs produced to that procedure. Generally, one (1) radiograph shall be sufficient to qualify a procedure sheet, however, for each pipe size below NPS 2 a specific qualification shall be required. The qualification radiographs submitted to the EMPLOYER for approval shall demonstrate that the following criteria have been satisfied:a)

The required sensitivity with the IQI on the source side (and if required, the film side) can be produced at the minimum density allowed.

b)

The weld length being examined is covered by interpretable film in one or more views.

7.3 TECHNIQUE IN GENERAL 7.3.1 Sources and Techniques a)

Preference shall be given to X-ray equipment. Where the use of X-ray equipment is not practicable, iridium 192 sources may be used.

b)

Preference shall always be given to a single wall technique if this is possible.

c)

Preference shall be given to a source inside/film outside technique if this is possible.

d)

If a double wall technique is necessary, it shall be with X-ray whenever possible.

e)

Where there is a choice between gamma-ray source inside/single wall and X-rays outside/double wall/single image, the former is preferable.

7.3.2 Screens Lead intensifying screens shall be used for RT at the thickness indicated below : Radiation

Screen Material

Front Screen Thickness (mm)

Back Screen Thickness (mm)

X-ray < 120 kV

Lead

None

0.1min..

120kV to 250kV

Lead

0.02 to 0.125

0.1min..

250kV to 400kV

Lead

0.05 to 0.16

0.1min..

Lead

0.02 to 0.16

0.16min..

Gamma-ray 192

Ir

The amount of back- scattered radiation shall be checked by placing a lead letter 'B' at the back of each cassette. Fluorometallic screens may be used, subject to the approval of the EMPLOYER. Fluorescent salt screens shall not be used. 7.3.3 Films Fine-grain high contrast film shall be used in conjunction with X ray sources. Ultra fine grain high contrast film shall be used for gamma radiography and may be used with X-ray equipment. In cases where the film is to be held flat or where the weight of the component is partly or fully taken by the cassette, rigid metal cassettes shall be used. For curved surfaces, where the film is to be curved, flexible cassettes may be used provided adequate precautions are taken to ensure good film-screen contrast. Where ready packed film cassettes are used, it is necessary to ensure that the thickness of the packed lead screens is adequate, see Clause 7.3.2. Films packed with lead foil of 0.02mm thickness shall only be used if vacuum packed and provided that the material thickness does not exceed 40mm.

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7.3.4 Film Identification Each radiograph shall have suitable symbols affixed to identify the job, the joint and the section of the joint. Radiographs of weld repairs shall be identified by the letter 'R' followed by the number of times the repair has been attempted, e.g. R1, R2 etc.. 7.3.5 Image Quality Indicators (IQI) a)

Type of IQI

Wire type IQI's conforming to BS 3971 or ASTM E747 shall be used with each radiograph. The minimum sensitivity achieved shall be in accordance with BS 3971. b)

Placement of IQI

Where possible, IQI's shall be placed on the source side of the weld. If the surface of the weld facing the radiation source is inaccessible for placement of an IQI, the procedure outlined in 13.2 of BS 2910 shall be followed. IQI's shall be placed on the weld at the edge of the area of interest with the wires orientated transversely to the fusion line, with the thinnest wire to the outside. The thickness of the material under an IQI shall be within 10% of the maximum thickness under examination. If the thickness range to be covered is large, an appropriate IQI shall be placed on both the maximum and minimum thickness to appear on each radiograph. c)

Number of IQI's

The requirements for structural welds shall be two (2) IQI's, one at each extremity of the area to be inspected or one at the centre of the radiation beam and one at the extremity of the area to be o inspected. For panoramic exposures, at least three IQI's shall be used spaced 120 apart. When a length less than 125mm is inspected, only one (1) IQI is required, located at the extremity of the area to be inspected. 7.3.6 Exposure Geometry "

The double wall, single image technique for outside diameters above 24 NPS shall only be used when no access to the bore surface is possible. When branches are subjected to RT they shall be radiographed using a multiple single exposure technique. Panoramic exposure of branch connections shall not be permitted. The length of weld under examination at each exposure shall be such that the thickness of the material at the extremities, measured in the direction of the incident beam, does not exceed, by more than 10%, the actual thickness at that point. 7.3.7 Focus to Film Distance The minimum values of focus to film distance shall be such that the calculated geometrical unsharpness shall approach the inherent unsharpness of the film screen combination, but in any case the unsharpness value shall not exceed 0.2mm for X-ray and 0.4mm for gamma ray radiography. 7.3.8 Film Density The film density over the entire weld length should lie within the range 2.0 to 3.0. Viewing conditions shall be suitable for viewing films of density upto 3.5. 7.3.9 Film Overlap The minimum film overlap shall be 20mm 7.4 FILM PROCESSING Radiographs shall be processed to allow storage of the film without deterioration for the duration specified in the relevant fabrication specification. The method of demonstrating this shall be identified in the procedures submitted in Clause 7.2.1. The radiographs shall be free from imperfection due to processing or other defects which would interfere with satisfactory interpretation. The radiographic contractor may be required at any time to demonstrate that the film can be processed, using the site facilities, to have a fog level of not more than 0.3.

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Radiographs should be stored in individual plastic pockets, in an environment with temperature and relative humidity controlled to levels recommended by the film manufacturer. Storage of radiographs in a microfilm form shall not be acceptable. 7.5 FILM STORAGE All unexposed films shall be stored in a clean dry place where the surrounding conditions will not detrimentally affect the emulsion. Open packages of film should be stored in a controlled environment at a temperature and relative humidity recommended by the film manufacturer. If there is any concern about the condition of the unexposed film, the EMPLOYER may request that the sheets from the front and back of each package (or a 900mm length from the front of each roll) be processed without exposure and shall satisfy the above stated fog level. 7.6 INTERPRETATION AND REPORTING All films shall be interpreted in the dry condition. Prior to being submitted to the EMPLOYER for final acceptance the radiographs and radiographic reports shall be accepted/rejected by the Radiographic Interpreter and reviewed by the CONTRACTOR's Inspector and endorsed. The radiographic report shall include the following information:a)

Procedure number.

b)

Radiographic number.

c)

Job identification.

d)

Date

e)

Weld & welder identification

f)

Radiographers name & qualifications

g)

Interpreters name & qualifications

h)

Strength of source

i)

Sensitivity.

j)

Density.

k)

details of screens, technique and film type.

l)

Results of examination.

TABLE 1 - REFERENCE BLOCK THICKNESS

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MATERIAL THICKNESS

CALIBRATION BLOCK 'T'

HOLE LOCATION

T