6651555-Scomi Natco - Ndt

0 22-Nov-06 AS SJ

REV DATE PREPARED CHECKED

REV

DESIGN CODE ASME SECT. VIII DIV. 1/2, 2004 EDITION

DOCUMENT No. 008-TOS06-J016/NDT/025 0

ACID GAS REMOVAL SYSTEM FOR JDA B-17 FIELD DEVELOPMENT

STATUS APPROVAL

PROJECT NAME

FOR INFORMATION

DESCRIPTION

OGPP ENGINEERING SDN BHD

TORSCO SDN BHDP.T WARU TEKNIKATAMA

TORSCO SDN BHD

SCOMI-NATCOCLIENT NAME

Total Pages : 47

CONTRACT NO. LOI DATED 6TH SEP. 2006

JOB NO. OGPP/06/J/008

NDT PROCEDURE

PRESSURE VESSEL ( ITEM NO.: V-1380, V-1310, V-1370, F-1340, F-1350 & F-1360)

(UT, RT & PENETRANT TEST)

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ULTRASONICTESTING










NDT HI-TECH INSPECTION SERVICES (M) SDN BHD

ULTRASONIC TESTING PROCEDURE

DOC No. : HT-UT-01REVISION : 0DATE : 31-10-06

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NDT HITECH INSPECTION SERVICES (M) SDN BHD

DESCRIPTION NAME SIGNATURE

PREPARED BY R.BASKARAN

ASNT LEVEL III

TECHNICAL MANAGER

APPROVED BYRAMAN OTHAYANAN

MANAGING DIRECTOR

REVISION STATUS:

S.NO REVISION No. DATE DESCRIPTION1 0 01-07-2004 FIRST ISSUE2345

Tota l Pages : 23

ULTRASONIC TESTING













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CONTENTS

1. SCOPE2. REFERENCE DOCUMENT3. QUALIFICATIONS4. RESPONSIBILITIES5. PROCEDURES6. REPORTING7. ACCEPTANCE CRITERIA8. ATTACHMENTS9. DOCUMENTS













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ABBREVIATION

API - AMERICAN PETROLEUM INSTITUTEAWS - AMERICAN WELDING SOCIETYASME - AMERICAN SOCIETY OF MECHANICAL ENGINEERSASTM - AMERICAN SOCIETY FOR TESTING MATERIALSASNT - AMERICAN SOCIETY FOR NON DESTRUCTIVE TESTINGMHz - MEGA HERTZIOW - INTERNATIONAL ORGANIZATION OF WELDINGIIW - INTERNATIONAL INSTITUTE OF WELDINGDAC - DISTANCE AMPLITUDE CORRECTIONFSH - FULL SCREEN HEIGHTdB - DECIBELLCRT - CATHODE RAY TUBEHAZ - HEAT AFFECTED ZONE













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1.0 SCOPE

This procedure is prepared to inspect base metal and fusion welded butt joints in ferriticsteel by Manual Ultrasonic Method.

2.0 REFERENCE DOCUMENTS

2.1 ASME Section V- Article-4, 5 & 23 (2001edition & 2003 addenda) –Boiler and Pressure Vessel Code

2.2 ASME /ANSI B31.3 (1999 edition & 2000 addenda ) –Chemical Plant and Petroleum Refinery Piping

2.3 AWS-D 1.1 (2002) – Structural Welding Code

3.0 QUALIFICATIONS

3.1 The Personnel who carry out Ultrasonic Testing in Plate & Pipe welds shall bequalified Level-II as per SNT-TC-1A.

3.2 Alternately a level-1 qualification is acceptable, provided the work is carried outunder the direct supervision of a qualified Level-2 Technician.

3.3 The Personnel who carry out ultrasonic testing in TKY Joints or nozzle weldsshall be qualified in any of the following.3.3.1 ASNT SNT-TC-1A Ultrasonic Testing Level-2 – Nozzle welds3.3.2 API RP-2X Ultrasonic Testing Par 2.3e.3.3.3 Where contract specification permits, a technician who does not meet the

requirements of section 3.3.1 thro 3.3.3 may be eligible to perform TKYor nozzle welds subject to the following conditions.

3.3.4 He shall posses qualification as per section 3.13.3.5 He shall demonstrate his ability to apply the special techniques required

for complex geometry weldments by completion of a representativepractical test.

3.3.6 The client shall approve him.

4.0 RESPONSIBILITIES

An Ultrasonic Operator / UT Technician shall be responsible for performing ultrasonicexamination according to this procedure.

5.0 PROCEDURES

5.1 EQUIPMENT

5.1.1 Ultrasonic Flaw Detector shall be Portable; Pulse echo unit with rectifiedA – Scan display. (E.g. Krautkramer–USK6, USK7, USK7D or equivalent).













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5.1.2 Straight beam search units shall be of standard manufacturer, twin crystalwith nominal frequency of 2.5 – 5 MHz crystal diameter of 10 – 15mm.

5.1.3 Angle Beam search units shall be of standard manufacturer, either twin orsingle crystal with a nominal frequency of 2.5 – 5 MHz and crystaldimensions of 8x9mm or 10mmØ.

5.2 REFERENCE BLOCKS

5.2.1 Reference blocks used for equipment calibration shall be as follows5.2.2 IIW or V1 Block5.2.3 V2 (Din 54122) Block5.2.4 IOW Beam Profile Block5.2.5 Basic Calibration Block of ASME Section-V, Article-5

5.3 COUPLANT

5.3.1 A suitable coupling medium for acoustic transmission is required.5.3.2 Glycerin, light machine oil, cellulose paste, non-corrosive gel or

equivalent may be used.5.3.3 Suitable high temperature grease shall be used as a couplant when doing

high temperature testing.

5.4 CALIBRATION OF EQUIPMENT

5.4.1 Manufacturers certificate of calibration shall be available with each newflaw detection unit. Annual re-calibration and certification shall be carriedout by manufacturers agent or recommended third parties.

5.4.2. In addition to the above, the ultrasonic operator shall carry out followingequipment checks prior to conducting any test.

Time base linearityScreen HeightLinearityAmplifier linearityProbe resolution

Equipment Performance checks as perAttachment-I

Probe Index Probe characteristics check as perAttachment-II

5.4.3 A record for all equipment checks shall be maintained in the standardformat.













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5.5 SURFACE CONDITION

5.5.1 Scanning surface shall be smooth, clean and free of scale, spatter, pitting,paint or any imperfection that might impair the coupling between theprobe and the work piece.

5.5.2 Dressing of weld profile may be carried out to eliminate or resolveconfusing surface echoes/mode conversions.

5.5.3 Where it is otherwise impossible for the ultrasonic beam to interrogate thefull cross section of the weld, the weld profile shall be dressed smooth.

5.6 TRANSFER CORRECTION

5.6.1 Transfer correction shall be carried out to compensate for differences insurface condition and material composition between calibration block andtest component. It is a requirement to determine a transfer correctionfactor and adjust basic sensitivity prior to any test. It shall be carried out asfollows:

5.6.2 Connect two – shear wave probes of same angle, type to the UFD intransmitter & Receiver mode.

5.6.3 Position the probes on the basic calibration block facing each other.5.6.4 Maximize the Full skip distance echo and keep it at 80% of full screen

height (Refer Fig.5.1). Mark the signal on the UFD screen.5.6.5 Reposition the probes in order to get the double skip distance echo and

maximize it (Refer Fig.5.2). Mark the signal on the screen.5.6.6 Join the two points together in a straight line marked across the screen

(Refer Fig.5.3).5.6.7 Without altering the gain control setting, transfer the probes to the surface

of the test piece. Using the same method described above, obtain peakedsignals at full and double skip distances. Join the peaks together in astraight line on the flaw detector screen.

5.6.8 The difference in dB between the two lines at comparable time base rangerepresents the transfer correction factor.

5.6.9 The transfer correction factor shall be added to the primary reference levelprior to the commencement of examination.













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Sketches for Transfer Correction Factor

Full skip distance

Transmit Receive

Figure 5.1

Double skip distance

Transmit Receive

Figure 5.2

80%FSHLine 1

Line 2

Test piece atFull Skip

Basic Cal. Blockat Full Skip

Test piece atDouble Skip

Basic Cal. Blockat Double Skip

TCF

Figure 5.3













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5.7 BEAM PATH CALIBRATION, SENSITIVITY SETTING AND DAC

5.7.1 Beam path Calibration and sensitivity setting shall be made by theultrasonic operator at the work location, immediately prior to hecommencement of test.

5.7.2 Straight beam calibration shall be made to display at least two back wallechoes on the CRT screen.

5.7.3 Straight beam sensitivity shall be adjusted such that the first back wallecho is set at 80% FSH.

5.7.4 Angle beam calibration shall be made for the beam path length that issufficient to ensure complete coverage of weld. This may vary from 0-0.5Skip Beam Path to 1.5 Skip Beam Path depends up on accessibility forscanning.

5.7.5 Angle beam sensitivity shall be set using a DAC curve in accordance withthe requirements of the applicable code as described in the attachment-III.Scanning sensitivity shall be 6 dB above the primary sensitivity.

5.7.6 The flaw detector unit shall have minimum 20dB amplitude in reserveabove basic sensitivity.

5.7.7 Recalibration of beam path shall be made every 30 minutes during testing,after any change of probe, coaxial cable or battery, or after any change ofwork location.

5.7.8 Suppression control shall be off during calibration.

5.8 TEST PROCEDURE

5.8.1 Straight beam examination shall be carried out on the base metal to ensurethat the angle beam scanning area is free of lamination or anyimperfections that might interfere with the angle beam test.

5.8.2 Any area of base metal with indications excess or equal to back wall echoor any area in which the back wall echo is completely lost shall bereported.

5.8.3 Straight beam examination of attachment welds shall be carried out whereaccess is possible.

5.8.4 Scanning patterns for angle beam probes shall be established inaccordance with size and geometry of the test joint. Selection of probeangles and scanning surface shall be designed to achieve optimumcoverage of weld metal volume.

5.8.5 Scanning patterns for each joint type shall be specified in a techniquesheet appended to this procedure.













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5.8.6 Probe movement during scans shall be a combination of lateral andtraversing actions. Each scan shall overlap by at least 10%. Rotational andorbital probe movements shall be used for assessment of indications.

5.8.7 Transverse scanning shall be carried out from weld cap if possible.Alternately scanning shall be done on the parent metal adjacent to weld atan angle of <15° to the weld axis.

5.9 EVALUATION OF INDICATIONS

5.9.1 All assessment and evaluation of indications shall be carried out withprimary reference level after deducting 6dB scanning sensitivity.

5.9.2 Care should be taken to ensure only relevant indications are reported asdiscontinuities.

5.9.3 Cross-sectional size of discontinuities shall be determined using 20dBdrop technique or maximum amplitude drop technique.

5.9.4 Length of discontinuities shall be determined using 6dB drop method.5.9.5 The type of discontinuity (i.e., Planar/Cylindrical /Spherical /Linear) shall

be evaluated by noting signal response to various scans and variousangles.

5.9.6 A reference zero datum mark shall be made on the work piece surface. Allrejectable discontinuities shall be marked relative to zero datum.

5.10 EXAMINATION OF REPAIRS

5.10.1 Repairs shall be re-examined using the same procedure used for theoriginal examination.

5.10.2 The extent of examination shall include the repaired area plus 100mm ateither end.

5.10.3 A new report, with relevant repair number, shall be written for all repairedwelds retested.

5.11 POST INSPECTION CLEANING

5.11.1 When required, post inspection cleaning shall be accomplished to removeresidual inspection materials (couplant) by flushing with a solvent basedcleaner then finally wiping with rags.

5.12 SAFETY

5.12.1 Care shall be exercised during inspection with due regard to the fact thatthe standard Ultrasonic Flaw Detectors used by the company are NOTconsidered intrinsically safe and Hot Work Permits shall be required forhazardous areas.













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6.0 REPORTING

6.1 Reporting requirements shall be as specified by the Client or the ContractDocument.

6.2 All examination results shall be reported in standard format.6.3 A sketch depicting cross-sectional area and circumferential location shall be made

for all rejectable discontinuities.6.4 All restricted areas that are not scanned with complete coverage shall be reported

with full explanation of restriction.

7.0 ACCEPTANCE CRITERIA

7.1 The acceptance criteria shall be in accordance with client’s requirements.7.2 However, unless otherwise specified the minimum acceptance criteria shall be in

accordance with the latest editions of the following documents:i) AWS D1.1 (2002) - For structural Steel Workii) ASME B31.3(1999 edition & 2000 addenda) - For Process Pipingiii) ASME Section-VIII Div.1 & 2 (2001edition & 2002 addenda ) –

For Pressure Vesselsiv) API 1104(1999) - For Pipelines

8.0 ATTACHMENTS

I - Equipment Performance CheckII - Probe Characteristics CheckIII - Construction of DAC Curve

9.0 DOCUMENTS

9.1 Technique sheet - HT-UT-T 0019.2 Technique sheet - HT-UT-T 0029.3 Technique sheet - HT-UT-T 0039.4 Hi-Tech”s Ultrasonic Examination Report9.5 Sketch Format for Ultrasonic Examination Report













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ULTRASONIC FLAW DETECTOR PERFORMANCE CHECK

1.0 INTRODUCTION

This is intended to provide detailed methods and techniques for assessment and calibration ofUltrasonic Flaw Detector, as required by HT-UT-01 Section 8.2.

2.0 TYPE OF EQUIPMENT:

As defined by sect ion 5.0 of HT-UT-01.

3.0 CALIBRATION PROCEDURE:

The instrument calibration shall be performed every three months.

3.1 Horizontal LinearityCalibrate the screen for the test range of 125mm using Single Crystal Transducer and IIW Block.Place the probe on 25mm thickness side and read the back wall echoes. The Percentage of erroris calculated based on actual reading and the expected reading. The error should not exceed ±2%of Test Range.

3.2 Screen Height LinearityA straight beam probe is coupled with the IIW (V1) block to get multiple echoes from 25mmback wall. Select any two echoes whose amplitudes are in the ratio of 2:1 with larger echo set at80% of full screen height. Adjust the gain successively without moving search unit and set thelarger indication from 100% to 20% of full screen height in 10% increments or 2dB steps if afine control is not available. Read the smaller indication at each setting. The settings andreadings must be estimated to the nearest 1% of full screen height. Deviation should not exceed±5% of Full Screen Height.

Alternately, a straight beam search unit shall be used on any calibration block, which willprovide amplitude differences with sufficient signal separation to prevent overlapping of the twosignals.

3.3 Amplitude Control LinearityCouple the angle beam search unit to IIW (V1) block and get multiple echoes from 25 mmthickness side. Select any echo and note its amplitude. Reduce the gain by 6dB and read theamplitude of the same indication. It must be 50% of the initial amplitude within ±10% of thenominal amplitude ratio. Perform this exercise for full range of Gain.













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The settings and readings must be estimated to the nearest 1% of full screen and the readingsshould fall within the limits of following table.

Other convenient reflectors from any calibration block shall be used with straight or angle beamsearch units.

Indication Set at % ofFull Screen Height

dB Control Change Indication Limits %of Full Screen Height

80 -6 dB 36 to 4480 -12 dB 18 to 2240 +6 dB 72 to 8820 +12 dB 72 to 88

4.0 RECORDS:

All calibration readings shall be recorded and documented till next calibration period andcalibration block identity shall be included in the ultrasonic calibration records.













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Equipment Type & Make: Probe Type: SingleSerial No: Serial No:IIW Block S.No. Dia. / Frequency:

Reference Document: HT-UT-01Rev.00 Date of calibration:Calibration Due Date:

TIME BASE LINEARITY

1 2 3 4 5

Deviation shall be with in ±2% of Test Range

SCREEN HEIGHT LINEARITYDescription

Reference Echo 100 90 80 70 60 50 40 30 20 Pass Fail

2nd Echo

Deviation %Deviation shall be with in ±5% of FSH

AMPLITUDE CONTROL LINEARIRYIndication Setat % of FSH

80804020

Note: FSH-Full Screen Height. TR-Test Range.

TESTED BY:

LEVEL-II

-126 72 to 88

72 to 8812

Result

dB Control Change Observed Indicationin % FSH Remarks

Block thickness(mm)

Amplitude (in FSH%)

Result

ASNT LEVEL-III

APPROVED BY:

36 to 4418 to 22

Deviation

-6

Required IndicationLimits in % of FSH

Test Range

NDT HITECH INSPECTION SERVICES (M) SDN.BHD

Back wall echoe Reading (mm)

ULTRASONIC FLAW DETECTOR PERFORMANCE CHECK

HT: FORMAT/UT/CAL-01













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ATTACHMENT – II

PROBE CHARACTERISTICS CHECK

1.0 INTRODUCTION

This has been written in order to provide detailed methods and techniques to evaluate theProbe’s characteristics.

2.0 TYPE OF PROBES & EQUIPMENT

As defined by section 5.0 of HT-UT-01.

3.0 PROBE CHARACTERISTICS

3.1 Probe Resolution3.1.1 Place 0° compression probe on the V1 (IIW) Block as shown in the figure 1. The echoes

from the bottom of the milled slot at 85mm and from the steps at 91mm and 100mmshall be clearly discernible on the screen.

3.1.2 Place shear wave probes on the IOW Beam Profile Block with the beam directedtowards the series of 5 side drilled holes. Al least 3 of the series shall be clearlydiscernible.

3.2 Probe IndexPlace shear wave probe on the V1 (IIW) block’s 100mm quadrant side as shown in the figure 2and maximize the eco from the quadrant. Hold the probe and measure the distance (d) fromblock edge to probe edge.

The probe index = (100 – d) mm.For example, if ‘d’ is 86mm, then

Probe index = 100-86=14mm.This distance shall be transferred to the probe.

Figure1

V1 (IIW) Block

Figure 2100 mm

d

V1 (IIW) Block













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3.3 Probe AnglePlace the shear wave probe on the V1 Block as shown in the figure 3 and maximize the echofrom 1.6mm hole.

Note the beam path and Probe angle is calculated using formula:Probe Angle = Cos-1(15/Beam Path)

3.4 20dB Beam Profile3.4.1 Position the shear wave probe on the IOW block with the beam directed at a selected

1.6mm hole and maximize the signal by moving probe backwards and forwards. Holdthe probe in the maximized position and adjust gain control to give 100% FSH. Make amark1 on the block which corresponds with the probe index point (see Fig. 4)

3.4.2 Move the probe gently forward until the signal height form the target hole has droppedto 10% FSH (i.e. 20dB). Hold the probe in this position and mark2 the probe indexposition on the block. (See Fig. 5)

Figure 3

1.6m

mho

le

V1 (IIW Block) – Probe Angle

Figure 4

Lead ing ed g e

Trailing Ed g eBeam Centre

Mark at maximized p o sit io n

Prob e mo vementt o maximize s ig nal

Ho rizontals t and-o ff

IOW Block













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3.4.3 Move the probe gently backward such that the signal goes back to maximum then fallsaway again to 10% FSH. Hold the probe in this position and mark3 the probe indexposition on the block. (See Fig.6)

3.4.4 Transfer the measurements of hole depth and probe stand off for each of three marksonto a flaw location slide or suitable plotting system.

3.4.5 Repeat the above steps for three other target holes at different depths.3.4.6 Complete the beam angle and profile plot by joining relevant points on the plotting

system. (See Fig.7)

4.0 CHECKLISTAll probe characteristics shall be entered in to the Probe Characteristics Checklist format: - HT:FORMAT/UT/CAL-02

Figure 5

20 d B Trailing Ed g e

M ark the p rob e indexat 1 0%s ignal height

M o ve p ro b e fo rwa rd untilS ignal heigh t d ro ps t o 1 0%

Figure 6

2 0 dBLeading Ed ge

Mark the p ro b e ind exat 1 0 %sig nal he ig ht

M ove p ro b e backward unt ilSig nal heig ht d ro p s to 10 %

Fig.7

Hole 1

Hole 2

Hole 3

Hole 4

Hole depth

Horizontal stand-off

Mark2 Mark1 Mark3

IndexPoint

Beam Profile Plotting













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UFD Model : Date of Testing :Serial No :

CHECKLIST FOR PROBE CHARACTERISTICS

ResultItem No Checklist Item ToleranceAccept Reject

Resolution - 0° Probe 3 Clearly definedindications

1

Resolution (Angle Probe) 3 Clearly definedindications

2 Probe Index 25 mm maximumfrom the edge

3 Probe Angle45°60°70°

±2°

4 Beam Profile(Leading/trailing edge)

45°60°70°

HT: FORMAT/UT/CAL-02













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x

x

x

Point 180% FSH

Point 2

Point 3

Time Base

Am

plitu

de

ATTACHMENT-III

1.0 INTRODUCTIONThis illustration is written to provide technical detail for the construction of DistanceAmplitude Correction (DAC) Curves as required by this written procedure.

2.0 EQUIPMENTAs defined by section 5.0 of HT-UT-01.

3.0 BLOCKS3.1 IOW Block for structural steel work weldments3.2 ASME Section-V – Basic Calibration Block for Pressure Vessels/Process Piping

4.0 METHODS4.1 Select a hole in the calibration block which falls out side of the Probe’s near zone. The

near zone length is calculated using the formula:

N = D2F /4V

where, N = Length of near zone (mm)D = Crystal diameter (mm)F = Frequency (MHz)V = Velocity (103m/s)

4.2 Position the probe on the block and pick up the signal from selected target hole.4.3 Maximize the signal by manipulation of probe.4.4 Adjust the gain and keep the maximized signal at 80% FSH and mark the signal peak

on the screen.4.5 Without further alteration select two more holes at suitable beam path to cover the

entire range/ thickness of the test material. Maximize the echoes by probe manipulationand mark the respective signal peaks on the screen.

4.6 Join together all the three points plotted on the screen to generate a DAC curve. (SeeFig.1)

Figure 1










NDT HITECH INSPECTION SERVICES (M) SDN. BHD



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TECHNIQUE SHEET – 1:

SCANNING TECHNIQUE FOR BUTT WELDS

a) Welds with single side access:

]

Angle Thickness Scan leg Surface Examination0° all n/a 1 & 2 Lamination check on Parent metal45° ≥25mm half 1 & 2 Root and lower weld volume

full skip 1 & 2 Upper weld volume and fusion faces60° 10-25mm half skip 1 & 2 Root, lower weld volume and fusion faces

>25mm full skip 1 & 2 Upper weld volume and fusion faces70° 10-25mm half skip 1 & 2 Root, lower weld volume and fusion faces

all half skip 1 & 2 Transverse scan of weld. (if cap is flushed tosmooth, scanning may be carried out from the weldsurface)

2.0 Welds with double side access:

Angle Thickness Scan leg Surface Examination0° all n/a 1 & 2 Lamination check on Parent metal45° ≥25mm half 1,2,3 &4 Root and lower weld volume60° ≥10mm half skip 1,2,3 &4 Root, lower weld volume and fusion faces

full skip 1,2,3 &4 Transverse scan of weld. (if cap is flushed tosmooth, scanning may be carried out from the weldsurface)

70° 10-25mm half skip 1,2,3 &4 Root, lower weld volume and fusion faces

half skipFull Skip

+ 1/2 Cap

Surface 1 Surface 2

half skip

half skip half skip

half skip

Surface 4

Surface 2

Surface 3

Surface 1













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TECHNIQUE SHEET – 2:

SCANNING TECHNIQUE FOR FULL PENETRATION / NOZZLE WELDS

a) Nozzle with ‘Set through’ or full penetration T-Joints:

Scan 1 0° Lamination check on parent metalScan 2/3 45°/60°/70° shear wave scanning for weld volume, root, HAZ and fusion faces

at ½ skipScan 3 - 0° scan for fusion at main member side and lamellar tearing in main member.

b) Nozzle or branch attachment ‘set-on’

Scan 1 0° Lamination check on the parent metal.Scan 2 45°, 60° scan for weld volume, fusion faces & HAZ at half and full skip

distance.Scan 3 60°, 70° scan for root at half skip.Scan 4 0° scan on main member to check main member side fusion, HAZ, Lamellar

tearing (if surface is accessible).Scan 5 If scan 2 & 3 is restricted due to non accessibility, a 45° scan for weld and

fusion at full skip shall be carried out.

Scan 4

Scan 4

Sc an 5













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TECHNIQUE SHEET - 03:

SCANNING TECHNIQUE FOR TKY JOINTS:

Scanning detail1. All scans to be carried out from branch member surface.2. 0° scan for lamination check on scan surface.3. 45°, 60°, 70° angle beam scan of weld metal at half and full skip as permitted by material thickness and

weld geometry.4. Local dihedral angle and weld geometry varies point to point. Therefore beam axis should be kept

perpendicular to the weld during angle beam scanning.

T oe zoneTransition

zone

Heel zone

MAIN MEMBER

BRANCHMEMBER

Scanning perpendicularto weld at all locat ions

Section through Toe zone

Mai

nm

embe

rM

ain

mem

ber

Section throughHeel zone

Section through Transition zone

Scan surface










RADIOGRAPHICTESTING










NDT HI-TECH INSPECTION SERVICES (M) SDN. BHD.

RADIOGRAPHIC TESTING PROCEDURE

DOC No. : HT-RT-01REVISION : 0DATE : 31-10-06

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ASNT LEVEL III

TECHNICAL MANAGER

APPROVED BY RAMAN OTHAYANAN

MANAGING DIRECTOR

REVISION STATUS:

S.NO REVISION No. DATE DESCRIPTION

1 0 01-07-2004 FIRST ISSUE

2

3

4

5

6

Total Pages : 17

RADIOGRAPHIC TESTING













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CONTENTS

1.0 SCOPE

2.0 REFERENCE DOCUMENT3.0 OPERATION4.0 QUALIFICATIONS5.0 RESPONSIBILITIES

6.0 RADIATION SAFETY7.0 PROCEDURES8.0 ATTACHMENTS

9.0 DOCUMENTS













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ABBREVIATION:

API - AMERICAN PETROLEUM INSTITUTEAWS - AMERICAN WELDING SOCIETYASME - AMERICAN SOCIETY OF MECHANICAL ENGINEERSASTM - AMERICAN SOCIETY FOR TESTING MATERIALSRPS - RADIATION PROTECTION SUPERVISORNRPB - NATIONAL RADIATION PROTECTION BOARDIQI - IMAGE QUALITY INDICATOR













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1.0 SCOPE

This procedure is applicable for Radiographic Examination of butt joints of Pressure vessels,Pipelines, Process Piping, and Structural work involving Carbon steel, Stainless Steel and itsalloys using gamma radiation.

2.0 REFERENCE DOCUMENTS

2.1 ASME Section V – Article 1, 2 & 22 (2001edition & 2003 addenda )2.2 ASME /ANSI B31.1 (1998) / B31.3 (1999 edition & 2000 addenda )2.3 AWS-D 1.1 (2002)2.4 API-1104 (1999)

3.0 OPERATION

The exposure device and related equipments used to achieve the above scope shall be carried outby a team of 2 personnel as a minimum. (Radiographer Level-II and a Radiographer Level-I orAssistant).

4.0 QUALIFICATIONS

The Personnel who carry out Radiography shall be qualified Level-II as per SNT-TC-1A, 2001.

5.0 RESPONSIBILITIES

5.1 Radiographer Level-II is responsible for selecting appropriate Techniques, ensuring SiteSafety, Processing, and Interpretation as per applicable codes.

5.2 Radiographer Level-I shall assist the Level-II to achieving the above.

6.0 RADIATION SAFETY

6.1 Duties of the radiographer includes personnel protection and protection of general publicaccording to the latest maximum permissible limits. All work shall be carried out in linewith the regulations of RPI, Singapore and modified as and where necessary by client’ssafety standards.

6.2 The Company’s Radiation Protection Officer (RPO) shall be a qualified person andcertified by a Atomic Energy Licencing Board (AELB). He is responsible for overall sitesafety, Dosimetry, and Handling of Emergency situation.













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7.0 PROCEDURES

7.1 EQUIPMENT

Remotely operated projectors shall be used such as Amertest-660 or equivalent. Ir.192 isotopewith maximum activity of 50 Curies shall be used.

7.2 FILMS

7.2.1 Type-I or Type-II films shall be used, as described in ASTM-E94 to producesatisfactory radiographs.

7.2.2 All Double Wall Double Image Techniques and welds with less than 12 mm wallthickness shall be radiographer using Type-I films.

7.2.3 Films shall be stored in a clean, dry place that is free from radiation, excessiveheat, undue pressure, or chemical vapor.

7.3 LEAD INTENSIFYING SCREENS

7.3.1 Lead foil intensifying screens shall be used at front and back of the film. Film andscreens shall be placed together and sealed inside a light proof cassette,maintaining good contact throughout the exposure.

7.3.2 For Iridium-192, Front and Back screen thickness shall be 0.05-0.15mm and 0.15mm minimum respectively.

7.3.3 Lead screens shall be maintained clean and free of scratches, dust and moisturethat might create film artifacts and impair radiographic quality.

7.4 TECHNIQUES

7.4.1 Double Wall Single Image technique shall be used for pipe diameter greater than76.2mm. (Refer to figure 1 for shooting sketch and technique details).

7.4.2 Double Wall Double Image (elliptical) technique shall be used for pipe diameterfrom 38.1mm (1.5”) up to 76.2mm (3”). (Refer to figure 2 for shooting sketch andtechnique details)

7.4.3 Double wall Double Image (Superimposed) technique for pipe diameter less than38.1mm. This technique may also be applied to pipe diameter up to 76.2mmwhere structural appendages restrict application of the elliptical technique orwhenever OD/ID ratio is greater than 1.4. (Refer to figure 3 for shooting sketchand technique details)

7.4.4 Single Wall Single Image Panoramic technique shall be used for pipe diametergreater than 500mm. This technique may also be applied to smaller pipe sizeswhere access is possible and geometric un-sharpness requirement is satisfied.(Refer to figure 4 for shooting sketch and technique detail).

7.4.5 Single Wall Single Image technique shall be used for plate welds and structural I-Beams.













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7.5 RADIOGRAPHIC QUALITY

7.5.1 Geometrical Unsharpness: Geometric Un-sharpness (Ug) of the radiograph shall bedetermined in accordance with: Ug = Fd/D

where, Ug = Geometric Un-sharpnessF = Effective Source sizeD = Distance from source to Objectd = Distance from source side of object/weld to the film.

The Geometric Unsharpness shall not exceed the following:

Material Thickness (mm) Ug maximumUnder 50.850.8 through 76.2Over 76.2 through 101.6Greater than 101.6

0.5 mm0.76 mm1.0 mm1.8 mm

Note: The material thickness is the thickness on which the penetrameter is based

7.5.2 Radiographic Sensitivityi) Radiographic sensitivity shall be determined by placing an Image Quality

Indicator (IQI) on the specimen in such a position as to cast an image onthe film.

ii) IQI shall be wire type conforming to DIN 54 109, or ISO typepenetrameters described in ISO 1027, or ASTM type penetrametersdescribed in ASTM SE-747/90 shall be used. or for ferritic and austeniticsteels. ISO type penetrameters described in ISO 1027, or ASTM typepenetrameters described in ASTM SE-747/90 shall be used. Tables 1, 2 &3 show the standard identification numbers found on the penetrameterpacks and the wire sizes found in the DIN type, ISO type and ASTM typetypical packs.

Table 1 - DIN Wire Type Penetrameter

DIN PackDesignation

Wire Diameter inch (mm)Corresponding Wire Number

1 FE DIN 0.125 (3.20)1

0.098 (2.50)2

0.078 (2.00)3

0.062 (1.60)4

0.050 (1.25)5

0.040 (1.00)6

0.032 (0.80)7

6 FE DIN 0.040 (1.00)6

0.032 (0.80)7

0.024 (0.63)8

0.020 (0.50)9

0.016 (0.40)10

0.013 (0.32)11

0.010 (0.25)12

10 FE DIN 0.016 (0.40)10

0.013 (0.32)11

0.010 (0.25)12

0.008 (0.20)13

0.006 (0.16)14

0.004 (0.125)15

0.004 (0.1)16













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Table 2 - ISO Wire Type Penetrameter

ISO PackDesignation

Wire Diameter inch (mm)Corresponding Wire Number

1 ISO 7 0.125 (3.20)1

0.098 (2.50)2

0.078 (2.00)3

0.062 (1.60)4

0.050 (1.25)5

0.040 (1.00)6

0.032 (0.80)7

6 ISO 12 0.040 (1.00)6

0.032 (0.80)7

0.024 (0.63)8

0.020 (0.50)9

0.016 (0.40)10

0.013 (0.32)11

0.010 (0.25)12

10 ISO 16 0.016 (0.40)10

0.013 (0.32)11

0.010 (0.25)12

0.008 (0.20)13

0.006 (0.16)14

0.004 (0.125)15

0.004 (0.1)16

Table 3 - ASTM Wire Type Penetrameter

ASTM SetDesignation Wire Diameter inch (mm)

A .0032 ( .081) .004 ( .102) .005 ( .127) .0063 ( .160) .008 ( .203) .010 ( .254)

B .010 ( .254) .013 ( .330) .016 ( .406) .020 ( .508) .025 ( .635) .032 ( .813)

C .032 ( .813) .040 ( 1.016) .050 ( 1.27) .063 ( 1.6) .080 ( 2.03) .100 ( 2.54)

D .100 ( 2.54) .126 ( 3.2) .160 ( 4.06) .200 ( 5.08) .250 ( 6.35) .320 ( 8.13)

iii) Radiographic sensitivity shall be calculated as follows:

a) For single image techniques

Sensitivity =

b) For double image elliptical techniques

Sensitivity =

c) For double image super imposed techniques

Sensitivity =

iv) 2% sensitivity is normally required. In certain circumstance,component geometry and exposure parameters make it impossible toattain required sensitivity. In such cases a revised sensitivity,acceptable to the client shall be determined from production testsunder the most favourable reasonably achievable.

Dia. Of thinnest visible wire x 100Weld thickness

Dia. Of thinnest visible wire x 100Wall thickness + Weld thickness

Dia. Of thinnest visible wire x 1002 x Weld thickness













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v) Wire penetrameter(s) shall be placed on the weld so that the lengthof wires is perpendicular to the length of weld a. The thinnest wireshall face the edge of film.

vi) IQI placed on the film side of specimen shall be identified withletter ‘F’.

vii) A comparator test shall be carried out on a representative weldspecimen with IQI placed on both source side & film side. Thesource side IQI shall be used to determine that the attainedsensitivity meets the requirements of 11.2.4. Then correspondingsensitivity value for the film side IQI shall be calculated. This valueshall be considered as the required sensitivity for subsequentproduction radiography with film side IQI.

7.5.3 Radiographic Densityi) Density shall be measured on the sound weld metal area using a calibrated

densitometer.ii) The density value shall not be less than 2.0 or more than 4.0.iii) Base fog density in unexposed film shall not exceed 0.3. Each new batch

of film shall be checked to ensure that the fog value is below the specifiedlimit.

7.5.4 Control of Scatteri) A lead letter ‘B’ shall be placed on the back of the film cassette during

exposure to determine the presence of Back Scatter radiation. If the imageof letter ‘B’ appeared on the film, additional backing strip of 1.6mm thickshall be placed behind the film cassette during exposures.

ii) Directional collimators shall be used for all non-panoramic techniques torestrict the radiation beam to the area under examination and thus reducethe effect of scatter.

7.6 SURFACE CONDITION

7.6.1 Visual Inspection shall be carried out prior to radiography to ensure that the weldis in a visually acceptable condition and free of spatter, slag and other surfacematter that may interfere with the process or interpretation.

7.6.2 The surface shall be in the as welded condition, except that local dressing ofsurface irregularities may be carried out, where a smooth contour would assistwith the evaluation of any discontinuities.













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7.7 IDENTIFICATION OF RADIOGRAPHS

7.7.1 Radiographs shall be identified by the following information that shall appear oneach processed film.

Project or Work order numberDrawing or Component NumberJoint Number (with repair status, if any)Radiographic section / Location in relation to marked datumDateThickness & DiameterWelder NumberOther information may be included as per the client’s requirement

7.7.2 Lead letters and numbers shall be used to identify radiographs. These should becarefully positioned to ensure that they do not encroach upon radiographic area ofinterest.

7.7.3 For panoramic exposures full identification is required only on the firstradiograph of the series. Only items i to iv of section 13.1 need to appear on theremainder.

7.7.4 Suitable reference datum marks shall be made on the surface of the work piece toenable traceability of radiographic results back to the correct location of weld.Paint marker or indelible ink shall be used to mark on the work piece.

7.8 OVERLAP OF FILM

7.8.1 Sufficient overlap shall be maintained to ensure 100% coverage of weld area within density requirements of section 11.3.

7.8.2 For circumferential butt welds the number of radiographs per weld shall not beless than that specified by the applicable code or standard.

7.8.3 A minimum overlap of 50mm of the original weld shall be given when repair areais radiographed.

7.9 PROCESSING

7.9.1 Film processing shall be carried out in a dedicated facility that is preparedexclusively for dark room type activities.

7.9.2 Processing chemicals shall be of a standard type from a recognized manufacturersuch as Kodak, Agfa, Dupont or Fuji.

7.9.3 Manufacturers recommendations for development time and temperature shallapply in all cases. Processing solution shall be mixed maintained, replenished anddisposed in accordance with manufacturers recommendations.

7.9.4 A degree of cleanliness and a satisfactory standard of house keeping shall bemaintained in the dark room at all times.

7.9.5 Prior to and during development, the processing solutions shall be agitated inaccordance with recognized standard practices.













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7.9.6 Radiograph shall be free of imperfections or artifacts due to processing whichmight interfere with interpretation in the area of interest.

7.10 INTERPRETATION OF RADIOGRAPHS

7.10.1 Interpretation of radiographs shall be carried out in a darkened room, using anapproved viewer with high intensity capacity.

7.10.2 All radiographs shall be free of artifacts or blemishes, which may interfere withinterpretation in the area of interest.

7.10.3 The radiographer shall only carry out interpretation of radiographs or otherpersonnel qualified to the same standard, as specified in section 4 of thisprocedure.

7.11. REPORTING

7.11.1 All examination results shall be reported in the standard format of NDT Hi-TechInspection Services (M) Sdn.Bhd.


7.12.1 The acceptance criteria shall be in accordance with client’s requirements.7.12.2 However, unless otherwise specified the minimum acceptance criteria shall be in

accordance with the latest editions of the following:i) AWS D1.1 (2002) - for structural steel workii) API 1104 (1999) - for Cross Country Pipelinesiii) ASME B 31.3 (1999 edition & 2000 addenda )-- for Process Pipingiv) ASME B 31.1 (1998) - for Power Pipingv) ASME Sec. VIII Div. 1 & 2 (2001 edition & 2002 addenda ) -

for Pressure Vessels

8.0 ATTACHMENTS

Figure-1 Double Wall Single Image (DWSI)Figure-2 Double Wall Double Image (DWDI – Elliptical)Figure-3 Double Wall Double Image (DWDI – Superimposed)Figure-4 Single Wall Single Image (SWSI-Panoramic)Figure-5 Single Wall Single Image (Plate)Figure-6.1&6.2 Single Wall Single Image (Pipe)

9.0 DOCUMENTS

9.1 NDT Hi-Tech’s Radiographic Examination Report Format













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Figure 1DOUBLE WALL SINGLE IMAGE (DWSI)

Alignment of Radiation Beam

The source of radiation shall be positioned so that the center of the projected beam passesthrough the centre of the section being examined. The beam shall be offset from the planethrough the weld by the minimum distance necessary to prevent the image of the front sideweld falling on the image of the other side. The film shall be placed diametrically oppositeto the source of radiation, in close contact with the weld.

Number of exposures:Unless otherwise required by contract specifications the following shall apply:

v Minimum of four exposures shall be made to radiograph schedule-160 or xxstrong material using gamma rays.

v Minimum of three exposures shall be made for other gamma radiography.

v Minimum of four exposures shall be made for X-ray radiography.

A

A

Source

IQIFILM

t

SourceSection A-A

Pipe

Film













- 12 -

Figure 2 DOUBLE WALL DOUBLE IMAGE (DWDI- Elliptical)

Offset of Radiation Beam

The source of radiation shall be offset 12° to 15° to the weld axis, so that the topsideweld shifts and forms viewable elliptical image of both pipe walls in one exposure. Thefilm shall be placed diametrically opposite to the x-ray tube or source of radiation inclose contact with the weld as a flat cassette allows.

Number of exposures:

At least two exposures shall be made at 90° to each other.

ASource

A

IQI

FILMt

Section A-A

Pipe

Film

IQI

Source

Offset













- 13 -

Figure 3DOUBLE WALL DOUBLE IMAGE (DWDI- Superimposed)

Alignment of Radiation Beam:The source of radiation shall be positioned so that the center of the projected beam passesthrough the center of the pipe in the plane of the weld, such that the images of the twosides of the weld are superimposed.

Number of exposures:

ASource

A

IQI

FILM

t

Section A-A

Pipe

Film

IQI

Source













- 14 -

At least three exposures 120° apart shall be made.

Figure 4SINGLE WALL SINGLE IMAGE (SWSI-Panoramic)

Alignment of Radiation Beam:The source of radiation shall be positioned inside the pipe so that the centre of theprojected beam passes through the center of the weld normal to the pipe surface.

Number of exposures:By careful positioning of the source at the centre of the pipe the whole circumferentialweld may be examined in one exposure.

A

AIQI

FILM

t

Section A-A

Pipe

Film

SourceSource

Film













- 15 -

Figure 5

SINGLE WALL SINGLE IMAGE (SWSI-Plate)

Alignment of Radiation Beam:The source of radiation shall be positioned so that the center of the projected beam passesthrough the center of the weld under examination, normal to the plate surface at that point.

Number of exposures:Unless otherwise required by contract specification, the length of weld examined shall notexceed the FFD/SFD, with the provision that the density at the outer edges of thediagnostic area shall not vary by more than -15% from the maximum density in soundmetal at the center of the diagnostic area.

A

A

IQI

Film

Source

Section A-A

Film

IQI

t

Source










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PENETRANTTESTING










NDT HI-TECH INSPECTION SERVICES (M) SDN.BHD.

PENETRANT TESTING PROCEDURE

DOC No. : HT-PT-01REVISION : .0DATE : 31-10-06

- 1 -




ASNT LEVEL III

TECHNICAL MANAGER

APPROVED BYRAMAN OTHAYANAN

MANAGING DIRECTOR

REVISION STATUS:S.NO REVISION No. DATE DESCRIPTION

1 00 01-07-2004 FIRST ISSUE

2

3

4

TotalPages8

LIQUID PENETRANTTESTING










HI-TECH NDT INSPECTION SERVICES (S) PTE LTD.

MAGNETIC PARTICLE TESTING PROCEDURE

DOC No. : HT-PT-01REVISION : 4.0DATE : 02-01-2004

- 2 -

CONTENTS1.0 SCOPE

2.0 REFERENCE DOCUMENT3.0 QUALIFICATIONS4.0 RESPONSIBILITY

5.0 TESTING MEDIA

6.0 INSPECTION PROCEDURE

7.0 REPORTING8.0 ACCEPTANCE CRITERIA9.0 DOCUMENTS













- 3 -

ABBREVIATION:

ASME - AMERICAN SOCIETY OF MECHANICAL ENGINEERSASTM - AMERICAN SOCIETY FOR TESTING MATERIALSPT - PENETRANT TESTING













- 4 -

1.0 SCOPE

This procedure specifies the examination of non-porous and metallic material using liquidpenetrant testing to detect the discontinuities, which are open to the surface.

2.0 REFERENCE DOCUMENT

2.1 ASME Section V – Article-1,6 & 24 (2001edition & 2003 addenda )2.2 ASME / ANSI B31.1 (1998) & B31.3 (1999 edition & 2000 addenda )2.3 ASTM E165 – Standard Recommended practice for PT2.4 AWS D1.1 (2002)2.5 API 1104 (1999)

3.0 QUALIFICATION

3.1 The person who performs PT shall be qualified to level-II as per ASNT SNT-TC-1A in PT.

3.2 Alternatively a level I qualification is acceptable provided the work is done underthe supervision of a level II.

4.0 RESPONSIBILITY

4.1 NDT Technician shall be responsible for performing Penetrant Testing accordingto this procedure.

5.0 TESTING MEDIA

5.1 Only approved penetrant testing system consisting cleaner/remover, penetrant anddeveloper shall be used.

5.2 Colour contrast method utilizing solvent removable penetrant and non-aqueouswet developer shall be used to carry out inspection.

5.3 The Penetrant system shall be of a manufacturers standard type from recognizedmanufacturers include Magnaflux, Ardrox Brent Chemicals etc.

5.4 Control Of Contamination:Certification of contaminant content for all liquid penetrant materials used onnickel base alloys, austenitic stainless steels, and titanium shall obtain frommanufacturers with manufacturers name, batch numbers and test results inaccordance with (a) and (b) below.(a) When examining nickel base alloys, all materials shall be analyzedindividually for sulfur content. The sulphur content shall not exceed 1% of theresidue by weight.(b) When examining austenitic stainless steel or titanium, all materials shallbe analyzed individually for chlorine and fluorine content. The total chlorine plusfluorine content shall not exceed 1% by weight.













- 5 -

6.0 INSPECTION PROCEDURE

6.1 SURFACE PREPARATION6.1.1 The surface to be examined shall be free from rust, scale weld spatter, dirt,

scale, paint, oil, grease or any other impurity, which might mask thediscontinuities.

6.1.2 Power grinding, shot and grit blasting shall not be used for cleaning thesurface.

6.1.3 Welded surface after removing oxides and flux shall be consideredsuitable for liquid penetrant testing provided the surface condition doesnot create difficulties in the examination or interpretation of the results.

6.1.4 Where machining or heat treatment is involved, Penetrant Testing shall beperformed after final machining and heat treatment, unless otherwisespecified by design or specification.

6.1.5 The test surface and adjacent area within one inch of the area beingexamined shall be cleaned using cleaner/remover and thoroughly wipedusing clean cloth. After wiping any residual solvent shall be allowed toevaporate.

6.1.6 The surface temperature of the material to be examined and the penetrantshall be in the range of 16º to 52º Celsius.

6.2 PENETRANT APPLICATION6.2.1 Penetrant shall be applied by brushing, spraying or flooding. The surface

to be examined should be thoroughly and uniformly coated with thepenetrant and shall be kept for the time period of 10 to 15 minutes. Anyexcess penetrant shall be allowed to drain from the part being examinedwhilst still allowing for proper penetrant dwell time.

6.3 REMOVAL OF EXCESS PENETRANT6.3.1 Excess penetrant shall be removed by first wiping the surface thoroughly

with a clean lint-free cloth after completion of dwell time. Whilst wipingcare should be taken to avoid back and forth movement. Because wipingback and forth will cause reapplication of some penetrant removed by theearlier movement.

6.3.2 Remaining traces of penetrant shall be removed by wiping the surfacewith a clean, lint-free cloth lightly dampened with cleaner/remover.

6.3.3 Drying of the test area surface shall be done by normal evaporation anddrying time shall not be more than 5 minutes.

6.4 APPLICATION OF DEVELOPER6.4.1 Prior to application, the developer suspension shall be thoroughly shaken

to ensure adequate dispersion of suspended particles.6.4.2 The developer shall be uniformly applied in a thin coating to the test

surface by spraying.













- 6 -

6.4.3 The test surface shall be kept dry during the development process.6.4.4 The development time shall not be less than seven (7) minutes, and no

longer than thirty (30) minutes after developer has been applied.6.4.5 If the surface area to be examined is large, then a stage-by-stage

examination shall be carried out.

6.5 INTERPRETATION AND EVALUATION6.5.1 Adequate illumination is required, either natural daylight or artificial white

light for the proper evaluation of penetrant indications.6.5.2 Observation of the test surface whilst applying the developer will assist as

an aid to the evaluation of the test item.6.5.3 Bleeding out of the dye penetrant will indicate mechanical discontinuities

on the surface.6.5.4 Machining marks or surface conditions may also produce similar

indications, which may not be relevant. Any indications that are believedto be non-relevant shall be re-examined after surface conditioning toverify the presence of discontinuities.

6.5.5 Relevant indications are those that result from mechanical discontinuities.Linear indications are those in which the length is more than three timesthe width. Rounded indications are circular or elliptical with length lessthan three times the width.

6.6 POST CLEANING6.6.1 Post cleaning is necessary in cases where residual penetrant or developer

could interfere with subsequent processing or with service requirements.6.6.2 Penetrant and developing materials shall be removed by wiping the

surface with a dry cloth. A cleaning agent /solvent may be used to assist incleaning surface.

7.0 REPORTING

7.1 All test results shall be recorded and reported in the Liquid Penetrant Test Report.


8.1 The acceptance criteria will be dependent upon the client’s requirements.However, unless otherwise specified the minimum acceptance criteria shall be inaccordance with latest edition of the following:8.1.1 ASME Section-VIII Div.1 & 2 ( 2001edition & 2002 addenda)

for pressure vessels8.1.2 ASME / ANSI B31.1 (1998) for power piping8.1.3 ASME / ANSI B31.3 (1999 edition & 2000 addenda ) for process piping.8.1.4 AWS D1.1 (2002)8.1.5 API 1104 (1999)










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