ITEC RT Procedure

NS-EN ISO 9001-2008. Certificate No 1221

EFFECTIVE DATE: 23 DEC 2013 REV: 0 DOC NO: WI-RT-01 PAGE NO: Page 1 of 19

RADIOGRAPHY TESTING

PROCEDURE

THIS PROCEDURE CONTAINED HEREIN IS

T H E PROPERTY OF ITECSOLUTIONS

QUALITY GROUP PTE LTD WHERE IS ISSUED

AND CONTROLLED BY THE MANAGER AND

SHALL NOT BE REVISED, AMENDED OR

ANYWAY ALTERED WITHOUT HIS APPROVAL.

Rev Date Prepared by Reviewed & Approved by0 23/12/2013 Y.ARUN

Branch ManagerV.S.Naidu

Technical Manager

SIGNATURE/STAMP SIGNATURE/STAMP

iTecSolutions Quality Group Pte. Ltd. Tel: (65) 6569 2636 6,Jalan Pesawat . Fax: (65) 6569 3437Singapore 609964.

Business Reg No:201118949RThis Document is property of IQG. No reproduction is allowed without prior to written

permission from the management of IQG. Violaters may be prosecuted.



TABLE OF CONTENTS Page

1. Introduction……………………………………………………………3

2. Scope…………………………………………………………………..3

3. Reference……………………………………………………………...3

4. Personnel Qualification………………………………………………4

5. General Requirements ……………………………………………....4 - 5

6. Radiation Source………………………………………....................5

7. Intensifying Screen…………………………………………………...5

8. Back Scatter………………………………………………………......5

9. Radiographic Film………………………………………………...…..6

10. Image Quality Indicator……………………………………………….6 - 7

11. Examination Radiographic Technique……………………………...8

12. Geometrical Unsharpness Limitation…………………………….....9

13. Manual Film Processing…………………………………………..….10

14. Evaluation of Radiographic Quality…………………………………10

15. Interpretation of Radiographs…………………………………….....11

16. Acceptance Criteria………………………………………………......11

17. Report…………………………………………………………………..11

Attachment 1 – 1A…..…………………………………..………...12 -13 Attachment 2………………………………………………………….14 Attachment 3………………………………………………………….15 Attachment 4…………………………………….……………………16 Attachment 5………………………………………………………….17 Attachment 6………………………………………………………….18 Attachment 7 ....……………………………………………………. 19






1. INTRODUCTION

This procedure details the requirements for the detection of cracks, voids, porosity, inclusions, inadequate penetration and lack of fusion beneath the surface of a weld by Radiography Testing to be carried out by ITG Pte Ltd. This procedure meets the minimum requirements of codes, standards and major projects specifications a listed out in Section 3 of this procedure.

2. SCOPE

2.1 This procedure outlines the materials, method and acceptance standards to be used in the examination and evaluation of welds and materials, utilizing radiographic testing method with gamma-ray Iridium 192 source equipment.

2.2 This procedure shall be utilized to examine steel, copper alloys, and high nickel alloys of thickness up to 63.5mm when gamma-ray of Iridium 192 shall be used.

2.3 The procedure applies to the radiographic examination of plate to plate and pipe to pipe full penetration butt joint weldments ; and castings.

2.4 When specified by a referencing code section, the method described in this procedure shall apply. Should there be any conflict arising between this procedure and the referencing code section used it shall be resolved, noted and agreed by all parties concerned prior to commencement of the inspection

3. REFERENCE DOCUMENTS

The procedure was written in accordance with the requirements of and in compliance with the requirements of the following standards and codes with latest editions.

3.1 ASME BPV Code section V Art. 2 Non Destructive Examinations.3.2 ASTM E-94 Standard Guide for Radiographic Examination.3.3 ASME B31.1.ASME Code for Pressure Power Piping.3.4 ASME B31.3.ASME Code for Pressure Process Piping.3.5 API 1104 Welding of Pipelines and Related Facilities.3.6 AWS D1.1. Structure Welding Code – Steel.3.7 BS EN 1435 NDE of Welds – Radiographic Examination of welded joints.3.8 ABS Guide for Nondestructive inspection on Hull welds.






4. PERSONNEL QUALIFICATION

Personnel performing Radiographic examination to this procedure shall be qualified in accordance with the requirements of ITG Pte Limited Company’s written practice WI-NDT-01 Rev.0 in accordance with ASNT Recommended Practice No. SNT-TC-1A 2006 Edition, Personnel Qualification and Certification. The levels of qualification and certifications are as follows:

4.1 SNT-TC-1A Level II minimum is required for evaluation and interpretation. Complete qualification records for personnel are maintained on file by the Level III Examiner.

4.2 Equivalent level of certification to 4.1 obtained via an internationally recognized independent organization such as CSWIP or PCN.

4.3 Personnel performing Radiographic examination shall be registered with the Centre for Radiation Protection and Nuclear Science (CRPNS) as a radiation worker and shall comply to local Radiation Safety Regulations as well as the ITG Pte. Ltd. “Safety Requirement and Emergency Procedure” manual.

5. GENERAL REQUIREMENTS

5.1 SURFACE PREPARATION

The areas to be examined shall be free of any irregularities which could interfere with interpretation. Weld ripples, edges, or weld surface irregularities are allowable to the extent that they do not mask defective areas or interfere with radiographic interpretation. Weld edges shall blend smoothly into the base metal. The finished surface of the reinforcement of all butt-welded joints may be flush with the base metal or may have a reasonably uniform crown not to exceed the following thickness:

Thickness of Base Metal Thickness of Reinforcement ________(mm)_________ ___ (mm)______ __

12.7 and under 1.6 12.7 to 25.4 2.4 25.4 and over 3.2






5.2 IDENTIFICATION AND MARKING OF FILMS AND OBJECTS.

5.2.1 Lead identification markers, shall be placed on all sections being radiographed. Markers shall be placed on the source side of the object being radiographed. The distance (area of Interest) between any two adjacent markers shall not be more than 12 inches(300mm).

5.2.2 There shall also be an identification on each film showing the contract number, client name, project name, date, welder(s) number,thickness, weld seam or part number identification being radiographed. Repair shall be identified by letter “R” plus the repair number. The location of Identification markers shall be accurately made on each weld seam or part tested, by permanent markings on the base metal adjacent to the weld by waterproof indelible crayon or dye markings.

6. RADIATION SOURCE

6.1 Gamma ray source of radioactive isotope, Iridium 192 shall be used.

6.2 Source container used shall be equipped with an automatic locking Device. The container may be Sentinel 880 series gamma projector or INC IR-100 gamma projector and equivalents local authority approved type.

6.2 Physical source sizes shall be 2mmx2mm/3mmx3mm/2mmx3mm.

7. INTENSIFYING SCREEN

7.1 Front and back lead f oil intensifying screens with a minimum thickness 0.005” shall be used for radiography.

7.2 Complete contact between screens and film shall be maintained during the exposure.

7.3 Screens shall be free from scratches, dents, grease, dirt, and other foreign material.

8. BACK-SCATTER

8.1 A lead symbol “B”, with minimum dimensions of 12.7mm in height and 1.6mm in thickness shall be attached to the back of each film holder during each exposure to determine if backscatter radiation is exposing the film, If a light image of the ”B” appears on the darker background of the radiograph, the radiograph shall be considered unacceptable.






8.2 When backscatter is likely to occur such as the film positioned near a wall, flooring or item, a lead sheet shall be placed behind the film cassette to minimize the scatter effects.9. RADIOGRAPHIC FILM

9.1 The film used shall confirm to ASTM E 94 Class I or II. All film shall be dated and be utilized prior to the shelf-life expiry date. Film types to be used shall be as listed but not restricted to the following:

9.1.1 Agfa-Gevaert Structurix Type I D4 and Type II D7.9.1.2 Kodak Industrex Type I MX 125 and Type II AA 400.9.1.3 Fuji film Type I Fuji 80 and Type II Fuji 100.

9.2 Film sizes shall be 4”x 10” and 4”x15”. Type II film which is medium speed, fine grain factor and high contrast shall be used. Type I film shall be used only when Type II films cannot achieve the required sensitivity. 10. IMAGE QUALITY INDICATOR (IQI OR PENETRAMETER)

10.1 Penetrameter or Image Quality Indicator (IQI) shall be made of material, radiographically as dense as the material under examination.

10.2 Penetrameter shall be placed on the source side of the component /weld. When it is impractical to place penetrameter on source side, penetrameter shall be placed on the film side of the weld or part, and a lead letter “F” shall be place adjacent to the penetrameter. This however, is not applicable to double wall double image (DWDI) technique.

10.3 Placement of hole type penetrameter shall be adjacent to the weld, preferably about 1/8” (3.18mm) to ½” !12.7mm) away from the toe of the weld.

10.4 Penetrameter shims shall be required when a weld reinforcement or backing ring is not removed. Shims of material radiographically similar to the weld metal shall be placed under the hole penetrameter so that the total thickness of the shim and the penetrameter is the same as the total weld thickness, including wall thickness, plus backing ring, if used and not removed.

10.5 Placement of wire type penetrameter shall be on the weld so that the length of the wire is perpendicular to the length of the weld. The wire penetrameter shall be placed on the source side of the weld and towards one end ( or one at each end if the weld length is greater than 10” ) of the length being radiographed, with the thickest wire towards the centre of its length.iTecSolutions Quality Group Pte. Ltd. Tel: (65) 6569 2636 6,Jalan Pesawat . Fax: (65) 6569 3437Singapore 609964.





10.6 ASTM Penetrameter ( hole or wire type) shall be selected in accordance with ASME V Article 2 Table T-276 or AWS D1.1 Code, Section 6 Table 6.6 (see attachment 1 and 2) to meet the specified referencing code section.

10.7 DIN 62 Fe wire type and DIN Cu wire or EN type penetrameter shall be applicable to this procedure. The penetrameter or IQI shall be of a material similar to that of the material under examination. The use and selection of the penetrameter or IQI in accordance with the required standard or specification specified.

10.7.I Example: IQI Irradiated thickness range

1-ISO-7 60 mm above 6-ISO-12 16 mm – 60 mm 10-ISO-16 0 mm – 20 mm 10.7.2 The smallest wire clearly visible on the radiograph shall be used in the following equation to assess the quality of the radiographic sensitivity.

tx I.Q.I. Sensitivity (%) = ---- x 100 ts

tx = Thickness of the smallest wire clearly visible. ts = Thickness of the specimen pus weld capping.

10.8 For one or more films are used for an exposure, at least one penetrameter shall be used for each film, except where the source is located at the center of the object and one or more films are used for a single exposure of a complete circumference, at least three penetrameter shall be spaced approximately 120 degrees apart.

10.9 Each number of penetrameter shall represent an area of essentially uniform radiographic density. If the density of the radiograph anywhere through the area of interest varies by more than -15% or +30% from the density through the body of the hole

penetrameter or adjacent to the designated wire of a wire penetrameter, than an additional penetrameter shall be used for each exceptional area or areas.






11. EXAMINATION – RADIOGRAPHIC TECHNIQUE.

A single-wall exposure shall be used for radiography whenever practical. This single-wall technique is use to radiograph non-tubular and tubular structures or components where both side of the surfaces are accessible. Where accessibility or pipe size prohibits the single-wall exposure technique, the double-wall exposure / single-wall view or double-wall exposure/double-wall view technique shall be used.

11.1 SINGLE-WALL TECHNIQUE (SINGLE-WALL/SINGLE IMAGE)

11.1.1 This technique the radiation passes through only one wall of weld ( material ) and used to radiograph circumferential and flat components joints. For pipe the source radiation shall be placed inside the pipe and the film on the outside of the pipe or vice versa. Panoramic ( 360º ) exposure shall be made if the source-to-object are satisfied; if not, a minimum penetrameter (IQI) shall be placed on the source side of the pipe. If impractical, it shall be placed on the film side of the pipe with a letter “F”.

11.2 DOUBLE-WALL TECHNIQUE (DOUBLE-WALL/SINGLE IMAGE)

11.2.1 This technique is used for materials and for welds in pipes where access or geometrical conditions prohibit single-wall exposure, the source shall be placed on the outside of the pipe and film on the opposite wall outside the pipe. ( see attachment 4 ). A minimum of three exposures shall be required to cover the complete circumference. ( see attachment 6 for number of films for coverage required). The penetrameter (IQI) shall be placed on the film side of the pipe. 11.3 DOUBLE-WALL TECHNIQUE (DOUBLE-WALL/DOUBLE IMAGE) 11.3.1 For materials or for welds in components 89mm (3½ in) or less in nominal outside diameter, this technique shall be used in which the radiation beam shall be offset from the plane of the weld at an angle sufficient to separate theimages of the source-side and film-side portions of the weld so that there is no overlap of the areas to be interpreted. A minimum of two exposures 90º to each other shall be required (see attachment 5 Exposure arrangement F). As an alternative, the weld shall be radio -graphed by superimposing the two welds (see attachment 5 Exposure arrangement G). There shall be a minimum of three exposures 60º to each other. Penetrameter (IQI) shall placed on the source side.






12. GEOMETRICAL UNSHARPNESS LIMITATION GUIDELINES

12.1 The following geometrical unsharpness value shall be used as a guide for determining minimum source to weld or object distance (D). Material Ug Thickness, in Maximum, in Under 2 0.020 2 through 3 0.030 Over 3 through 4 0.040 Greater than 4 0.050 Geometric Unsharpness Ug = Ft/D F = Source size T = Thickness N D = Source Object Distance

12.2 The source to object distance shall be determined from the formula Ug=Ft/D by making “D” the subject, therefore D=Ft/Ug.

12.3 Source to object distance shall not be less than the total length of film being exposed in a single plane and this provision shall not be applied to panoramic exposures.

12.4 The source to object shall not be less than seven times the thickness of weld plus reinforcement and the backing strip.

13. MANUAL FILM PROCESSING

13.1 Developer shall be tested with an pre-prepared exposed film strip prior to processing.

13.2 Manual processing chemical solution for developer and fixer shall be Agfa Structurix or Kodak Industrex or equivalents. Processing chemical solution used shall be qualified during the qualification of NDT procedures.

13.3 The recommended processing temperature and time for developers shall be at 20ºC (60ºF) at 5 minutes or as per manufacturer’s recommendations. Films shall be agitated periodically throughout the development.

13.4 Films shall be immersed 30 to 60 seconds at 18ºC to 21ºC (65º to 70ºF) in the stop bath solution (consist acetic acid) from Agfa or Kodak brand. Moderate agitation and then transferred to the fixing bath.






13. MANUAL FILM PROCESSING (Cont’d) 13.5 Keep the film in the fixer until fixing activity is complete. The fixing

time shall be twice the clearing time (the disappearance of the original diffuse yellow milkiness ) or maximum 15 minutes. The films shall be agitated vigorously when first placed in the fixer and at least every 2 minutes thereafter during the course of fixation to assure uniform action of the chemicals.

13.6 Films shall be washed in running water so circulated that the entire emulsion area receives frequent changes. For a proper washing, the bar of the hanger and the top clips shall always be covered completely by the running water. Washing time shall be at least 30 minutes at 15.5ºC to 26.5ºC (60ºF to 80ºF) of water temperature.

13.7 Agfa Structurix Drier shall be used for instantly drying of films. If conventional drier to be used, the films shall immersed for 1 to 2 minutes in a wetting agent, then allow the bulk of the water to drain off before the films are placed in the drying cabinet.

14. EVALUATION OF RADIOGRAPHIC QUALITY

Evaluate the radiographic quality by the image of a properly located penetrameter and the following film quality requirements:

14.1 The images of the identifying numbers, the penetrameter outline, and the specified hole shall appear on the radiograph.

14.2 The film density through the image of the penetrameter and the area of interest for single viewing shall 2.0 minimum and 4.0 maximum for the radiographs. The density range of 2.0 to 3.0 shall be maintained unless special arrangement is made from the adequate viewing of higher density film. Film density verification shall be by comparison with the calibrated density strip and densitometer available at Megtek Pte Ltd office.

14.3 All radiographs shall be free from mechanical, chemical or other processing defects that could interfere with proper interpretation of the radiograph.

14.4 The sensitivity to be achieved shall be in accordance to ASME V Art. 2 T-283 or AWS D1.1. Section 6.17.1. The 2% minimum sensitivity shall be base on single wall thickness when doubl wall techniques

are used with single wall viewing.






15. INTERPRETATION OF RADIOGRAPHS

15.1 The film viewer should provide light of intensity that will illuminate the average density areas of radiographs without glare and it must diffuse the light evenly over the viewing area.

15.2 The viewer shall be capable to review film density up to 4.0 and should have an intensity control switch to allow the selection of optimum intensities for viewing film.

15.3 Masks should be available to exclude any extraneous light from the eyes of the viewer when viewing radiographs smaller than the viewing port or to cover low-density areas.

16, ACCEPTANCE CRITERIA

16.1 Acceptance criteria shall be base in accordance to client specified in materials specifications or contractual documents for Acceptance and Rejection.

17. REPORT

17.1 Radiographic Report shall be made by interpreter on completion of each interpretation.

17.2 All applicable data/ information on the Radiographic Report related to the examination shall be filled. (see attachment 7 Radiographic Report).






ATTACHMENT 1:

ASME CODE






ATTACHMENT 1A

ASME CODE






ATTACHMENT 2AWS D1.1 Code






Attachment 3

SINGLE WALL/SINGLE IMAGE (SWSI)

Exposure Technique: Single WallRadiograph Viewing: Single Wall






Attachment 4

DOUBLE WALL/SINGLE IMAGE (DWSI)

Exposure Technique: Double WallRadiograph Viewing: Single Wall






Attachment 5

DOUBLE WALL/DOUBLE IMAGE (DWDI)

Exposure Technique: Double WallRadiograph Viewing: Double Wall

ATTACHMENT 6






ASA PIPE SCHEDULENO OF FILMS TO BE TAKEN

UPPER VALUE INDICATE PIPE THICKNESSLOWER VALUE INDICATE NUMBER OF FILM REQUIREDSch.NoPipe Size

20 30 STD 40 XS 60 80 100 120 160 XXS

½” 2.82

2.82

3.72

3.72

3.72

4.84

7.54

¾” 2.92

2.92

3.92

3.72

3.92

5.64

7.84

1” 3.42

3.42

4.52

3.72

4.52

6.44

9.14

1 ¼” 3.62

3.62

4.92

4.92

6.44

9.74

1 ½” 3.72

3.72

5.12

5.12

7.14

10.24

2” 3.92

3.92

5.52

5.52

8.74

11.14

2 ½” 5.22

5.22

7.02

7.02

9.44

14.04

3” 5.52

5.52

7.62

7.62

11.14

15.24

4” 6.03

6.03

8.63

8.64

11.14

11.54

17,15

5” 6.64

6.64

9.54

9.54

12.74

15.94

6” 7.14

7.14

11.04

11.04

14.34

18.35

21.95

8” 6.44

7.04

8.24

8.24

12.74

10.34

12.74

15.14

18.35

23.15

22.25

10” 6.44

7.84

9.34

9.34

12.74

12.74

15.15

18.35

21.45

28.65

25.45

12” 6.46

8.46

9.56

10.36

12.76

14.36

17.46

21.47

25.47

23.37

25.47

14” 7.96

9.56

9.56

11.16

12,76

15.16

19.07

23.87

27.87

35.77

16” 7.96

9.56

9.56

12.76

12.76

16.77

21.47

26.37

30.97

40.57

18” 7.96

11.16

9.56

14.36

12.76

20” 9.57

12.77

9.57

15.77

12.77

24” 9.58

14.38

9.58

12.78

28” 12.79

15.99

9.59

12.79

30” 12.710

15.910

9.510

12.710

32” 12.711

15.911

9.511

12.711

36” 12.512

15.912

9.512

12.712

42” 9.511

12.711

48” 9.511

12.713

Attachment 7

Radiographic Sample Test Report









Documents

ITEC RT Procedure