National Iranian Gas Company
IGAT V Booster Gas Compressor Stations
OTC Document Title
Document No.
UT Procedure
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NATIONAL NATIONAL IRANIAN IRANIA N GAS COMPANY COMPANY
IGA IGAT V Boos Bo oster ter Gas Gas Compr Com pressor essor Station
DOCUMENT DOCUMENT TITLE: UT PROCEDURE
SPY-3-0000-CM-PR-212
A. M.
P. K.
A. M.
AUTHOR
CHECK
QA
M. A. T. 5GCS AUTHORIZED
24 Aug '06 EP
MC
APPROVED
DATE OF ISSUE
D00 REV.
For Information Information PURPOSE OF ISSUE
National Iranian Gas Company
IGAT V Booster Gas Compressor Stations
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TABULAITON OF REVISED PAGES PAGE
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National Iranian Gas Company
IGAT V Booster Gas Compressor Stations
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National Iranian Gas Company
IGAT V Booster Gas Compressor Stations
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CONTENTS Page 1
Scope
4
2
Reference
4
3
Responsibility
4
4
Qualification of personnel
5
5
General requirement
5
6
Equipment and accessories
6
7
Calibration blocks and reference specimens
12
8
Distance calibration
16
9
Distance amplitude correction
16
10
Primary reference level and scanning sensitivity
17
11
Transfer value correction correct ion
17
12
Application UT examination
18
13
Parent metal evaluation
18
14
Inspection of welds
18
15
Discontinuity localization and size evaluation
21
16
Post cleaning
22
17
Acceptance standards
22
18
Defect marking and examination of repair
22
19
Reporting
23
20
Appendices
23
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National Iranian Gas Company
IGAT V Booster Gas Compressor Stations
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1. Scope
1.1. This procedure covers requirements for ultrasonic examination for fabrication & erection of piping and steel structure full penetration welds in ferrite materials, usually minimum thickness of 5/16 inch (8mm) to be fabricated for IGAT V Booster Gas Compressor Stations, contract No. 180502.
1.2. The purpose of ultrasonic examination is to determine and evaluate the severity of internal discontinuities in welds and base metal. This procedure describes the general requirements for ultrasonic testing of full penetration welds in ferrite materials, usually minimum thickness of 5/16 inch (8mm).
2. References
2.1. ASME Sec. V : Nondestructive Examination
2.2. ASME E164, A578, Nondestructive Examination (vol.03-03, 01-03)
2.3. ASME B31.3 : Process Piping
2.4. AWS D1.1 : Structural Welding Code
2.5. ASNT SNT-TC-1A : Recommended practice for NDT personnel qualification and certification
2.6. Project Specification : 602-000-PI-SP-010, 602-000-ST-SP-001
3. Responsibility
3.1. The QC engineer shall be responsible for cooperate with sub-contractor for NDE
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work. 3.2. The sub-contractor shall be responsible for managing of general NDE work.
3.3. The QA/QC Manager or his designee of Subcontractor shall be responsible for control of NDE sub-contractor and documents related to the NDE.
4. Qualificati on of Person nel
4.1. Personnel performing examination to this procedure shall be qualified as level II or III in accordance with ASNT SNT-TC-1A “ Recommended practice for NDT personnel qualification and certification” or equivalent in PCN / CSWIP certification systems.
4.2. Only Level II or Level III personnel shall interpret and evaluation test results to determine acceptability.
5. General requir ements
5.1. Surface preparation
5.1.1. The area adjacent to the weld to be examined shall be free of all weld spatters, loose particles, non-adhering mill scale or any other foreign matter that would interface with the free movement of search unit or with the transmission of ultrasound into the test part.
5.1.2. Preparation of welds for examination will be identified in the specific ultrasonic operating technique sheet.
5.1.3. Painted, primed or coated surfaces cannot be scanned.
5.2. Examination Coverage
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5.2.1. Welds shall be examined by moving the search unit over the examination surface so as to scan the entire volume.
5.2.2. The search unit will be moved laterally in zigzag pattern ensuring that the forward movement is perpendicular to the weld axis and overlap by at least 10%. 5.3. The rate of search unit movement for examination shall not exceed 152mm/sec1 unless calibration is verified at scanning speed.
5.4. Recording of indication level shall be made in respect to the reference level.
5.5. Information furnished to the NDE Subcontractor shall clearly identify the drawing No., materials category, thickness, weld No., welder(s), location and length of welds to be examined. A copy of the weld procedure applicable to each specific joint being examined shall be made available for the operators review, prior to commencement of the examination.
6. Equipment and accessori es The following equipment and accessories will be considered as a minimum to fulfill the requirements of this procedure and will be available to all technicians. The calibration certificate for the UT equipment, and the certificate of conformity for UT probes, calibration blocks are to be available on site for verification by certifying authority. and company.
6.1. The examination shall be conducted with a pulse-echo ultrasonic instrument, capable of generating, receiving and presenting the relevant pulses on a screen in the frequency range from 1 to 6 MHz. (e.g. Krautkramer USK6, USK7, USN 50 and
1
Refer to ASME Sec. V, Art V
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USN 52or equivalent). Instruments operating at other frequencies may be used if equal or better sensitivity can be demonstrated and documented.
6.1.1. Equipment qualification and calibration The operator shall carry out the following checks for calibration:
6.1.2. Any of the above checks found to be out of tolerance should be cause for system repair followed by full re-calibration of affected points.
Checks
Frequency
Ref. Documents
Amplitude control
At least once a
ASME Sec.V, Para
linearity
month
T533
Screen height
At least once a
ASME Sec.V, Para
linearity
month
T533
Horizontal linearity
At least once a
ASME E 164
month Internal reflection
At least once a
ASME E 164
week Resolution
At least once a
ASME E 164
week
6.1.3. The result of such calibration should be signed by contractor and certifying authority and should be maintained for reference in the NDT department and available for Company inspection as required.
6.2. Transducers
The following transducer or equivalent shall be used.
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6.2.1. Longitudinal wave search units
Type
Angle
Frequency
Crystal size
Make of Probe
Single crystal
O
4 MHz
10 mm dia
Kraut Kramer
Twin crystal
O
4 MHz
3.5 x 10 mm
Kraut Kramer
Single crystal
O
2 MHz
10 mm dia
Kraut Kramer
Twin crystal
O
2 MHz
3.5 x 10mm
Kraut Kramer
°
°
°
°
6.2.2. Shear wave search units
Type
Angle
Frequency
Crystal size
Make of Probe
Single crystal
45
2 MHz
10 mm dia
Kraut Kramer
Single crystal
60
2 MHz
10 mm dia
Kraut Kramer
Single crystal
70
2 MHz
10 mm dia
Kraut Kramer
Single crystal
45
4 MHz
10 mm dia
Kraut Kramer
Single crystal
60
4 MHz
8 x 9 mm
Kraut Kramer
Single crystal
70
4 MHz
10 mm dia
Kraut Kramer
°
°
°
°
°
°
6.3. Calib ration and reference block s 6.3.1. STB-A1, IIW Type 1 (Fig. 1) or IIW Type 2 block (Fig. 2) 6.3.2. IIW miniature block (Fig. 3) or STB-A3 (Fig. 4) 6.3.3. ASME basic calibration block (Fig. 5, 7) 6.3.4. IOW as calibration block
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Fig. 1 STB-A1, IIW Type 1 Block
Fig. 2 STB-A2, IIW Type 2 Block
Page 9 of 34
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Fig. 3 IIW Miniature Block
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Fig. 4 STB-A3 Block
6.3.5. A suitable couplant such as water based paste of cellulose gum, wall paper adhesive or coupling paste having good wetting characteristics should be used between the transducer and examination surface. The same couplant shall be used for calibration and examination.
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7. Calib ration block s and reference specimens
7.1. Material
7.1.1. Material from which respective calibration blocks and reference specimens are fabricated will be of the same product form and material specification or equivalent. The calibration block material will be completely examined with a straight beam search unit to ensure freedom from reflectors that exceed the back wall echo.
7.1.2. For the examination for weldments which have been subjected to post weld heat treatment the material from which the calibration block is fabricated will have received a similar PWHT process, and also a post weld heat treatment of at least 2 hr, if the calibration block contains weld prior to machine the reflectors.
7.1.3. When calibration block have not received heat treatment, transfer method shall be used to correlate the responses from the basic calibration block and component. Transfer is accomplished by noting the difference between responses received from the same reference reflector in the basic calibration block and in the component and correcting for the difference.
7.2. The surface finish of the calibration blocks will be as representative of the surface finish of the components as far as possible with suitable surface preparation or treatment, as practical, to simulate testing conditions.
7.3. Reference specimens for testing the welds (ASME Basic Calibration Blocks)
7.3.1. For examination in materials where examination surface diameter is greater than 20 inches, a flat basic calibration block, complying with the requirements indicated on figure 5 will be used. Reflectors will have side-drilled holes and
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surface notches oriented parallel to the longitudinal axis of annuals reference specimen.
7.3.2. For examination in material where the examination surface is 20 inches or less, curved annuals basic reference specimen will be used. The size and location of the surface notches and diameter of range covered by each blocks will be as shown in fig. 6 and 7.
7.3.3. A single reference specimen may be used to calibrate for examination on component surfaces in the ranges of curvature from 0.9 to 1.5 times the basic reference specimen diameter. Basic reference specimen thickness ranges will be as stipulated in figure 5. These specimens could be a section pipe of the same nominal size as one of the components being tested i.e. as off cut pipe being used in fabrication.
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Weld Thickness
Basic Calibration Block Thickness
Hole Diameter
1 in or less
3/4in. or t
3/32in.
Over 1in. through 2in.
1 1/2in. or t
1/8in.
Width=1/8in. to 1/4in.
Over 2in. through 4in.
3in. or t
3/16in.
Depth= 2%T or 0.04in.
Over 4in. through 6in.
5in. or t
1/4in.
Whichever is greater, into
Over 6in. through 8in.
7in. or t
5/16in.
the base metal.
Over 8in. through 10in.
9in. or t
3/8in.
Length= 2in. min.
Over 10in.
t±1in.
[See note 6]
Notch Size
Notes: a) Holes shall be drilled and reamed a minimum of 1-1/2in. deep, essentially parallel to the examination surface. b) Curved surfaces: for curved surface, two curved blocks, one for each representative curvature or two sets of calibration reflectors orientated 90 deg. from each other shall be used. c) Notches may be provided as required. The tolerance for hole diameter shall be ±1/32in. The tolerance on notch depth shall be +10% and -20%. The tolerance on hole location through the thickness shall be ±1/8in. d) For each increase in thickness on 2in. or fraction thereof over 10in., the hole diameter shall increase 1/16in.
Fig. 5 ASME Basic Calibration Block
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Fig. 6 Ratio limits for curved surfaces
Fig. 7 Angel beam calibration block dimension (Pipe welds)
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8. Distance calibr ation
The CRT will be calibrated for range using the international institute of welding STB-A1, type 1, 2 and STB-A3 calibration blocks, in the relationship of time versus distance (beam path length).
9. Distance amplit ude cor rectio n (DAC curv e)
9.1. For sensitivity calibration during all weld examination (Straight or Angle beam), DAC curves will be constructed for every search unit to be utilized at each particular range. Block used for DAC construction will be selected as appropriate from those as specified in para. 7.3.
9.2. DAC curves will be constructed as follow.
9.2.1. Place the probe on the calibration block to obtain a reflection from the hole that produces the greatest response.
9.2.2. Maximize the indication by manipulation and adjust to approx. 80% screen height using the calibration gain control. Make a mark on the CRT at the peak of the indication using an indelible fine tipped felt marker.
9.2.3. Points representing 20 % and 50 % of the primary gain are also to be constructed. Repeat b) and c) using reflections from every reflector that can be obtained within the beam length of the test range to be used, including those reflections obtained from skip, if the sound path is more than probes specific near field range.
9.2.4. Connect all points marked (minimum 3 points) with a smooth curving line, this line will be referenced to as the DAC curve the respective probe used and will apply for that particular material and configuration (or part geometry) only.
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9.2.5. DAC curves will be directly marked as the CRT time base screen cover with an indelible ink marker or superimposed using clear plastic, polyester or Perspex overlap. The DAC curve fail to search a level of at least 23 % of full screen height at the limit of its range, as represented on the time base, sufficient supplementary gain should be added to attain this level and the DAC adjusted accordingly.
10. Primary r eference level and scanni ng sensi tiv ity
10.1. The primary reference level will be that gain setting whereby reflectors in the applicable basic calibration block or reference specimen as described in para. 7.3 above, coincide with DAC curve constructed as described in para. 9.0 above. The primary reference level will be corrected for differences in surface character and attenuation between the basic reference block and the actual item under examination by method, as described in para. 11 herein. 10.2. Sensitivity settings for parent material examination with 0 compression wave will °
be that dB value where by the first back wall echo of the material reaches 80 % of full screen height, DAC curves will not apply for evaluation during this application. Scanning will be carried out at the same setting according to ASTM A578.
11. Transfer value c orr ection
11.1. Transfer value will be determined and used for all shear wave examination to compensate for differences in surface contour, finish, coating, and acoustical attenuation characteristics. This exercise will be performed for each nominal angle of refraction to be utilized for examination. To ensure that accurate transfer value correction factors are obtained, signal comparison will only be made in the “far field” area of the ultrasonic beam. 11.2. Transfer correction will be measured with the following way;
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11.2.1. Construct the DAC as per para. 9.0. 11.2.2. Using the primary search unit as the transmitter and a similar search unit as a receiver, position both on the basic calibration block facing each other, in a pitch and catches arrangement with the instrument in the dual transducer mode. 11.2.3. Maximize the indication and adjust the gain to allow the indication to peak at the DAC curve. Note the gain value. 11.2.4. Repeat steps a), b) and c) above on the component to be examined. The difference in gain values is the transfer value. This value may be positive or negative and adjustments will be made to the sensitivity settings accordingly and should be recorded in all the reports.
12. Appl icatio n o f UT Examination
12.1. The applicable specification are 602-000-PI-SP-010 and 602-000-ST-SP-001 12.2. When RT is required and is not practicable UT plus MT may be considered as an alternative subject to COMPANY approval. 12.3. UT may be substituted for RT where it is impractical to obtain an interpretable radiograph, subject to COMPANY review and approval.
13. Parent metal evaluati on
13.1. Thickness measurement
13.1.1. Any member from which scanning is to be conducted shall first be scanned with a 0 compression probe to establish the thickness. These results will be °
recorded. 13.1.2. Any areas of significant thickness variation, which could possibly affect calculation, will be highlighted, recorded and reported.
13.2. Parent metal examination
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13.2.1. The scanning of the adjacent base metal shall be performed to detect reflectors that might affect interpretation of angle beam results, and is not to be used as an acceptance-rejection examination. Locations and areas of such reflectors shall be recorded.
13.2.2. Ultrasonic examination within pipe end and shall be carried out according to ASTM A578. Any discontinuity (e.g. lamination) causing a reflection echo exceeding 50 % and accompanied by a 50 % loss of back reflection shall be considered as reject when the discontinuity area exceeds 100 mm.
14. Inspectio n o f welds
14.1. General
14.1.1. A minimum of two different probe angles should always be applied (see table 2) this is in addition to the straight beam probe required as per para. 12.
14.1.2. For butt joint welds, the examination shall be made from both sides of the weld axis from the accessible surface, wherever possible.
14.1.3. Upon discovering suspect indications both orbital and rotational scan will be carried out to evaluate the characteristics of the reflector.
14.1.4. Time base ranges as specified may be suitably readjusted by the operator in localized areas to highlight suspect deflections and subsequently assist in echo evaluation.
14.1.5. The normal scanning is carried out with at least 6 dB increased gain level, and that all defects sizes will be evaluated at a non-increased level.
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14.2. Longitudinal scanning
14.2.1. Scanning for longitudinal discontinuities in the weld body will be carried out with the angle beam at approximately right angles to the weld axis, from two directions whenever possible. Nominal angles of reflection to achieve this are stated in table 2.
14.3. Transverse scanning
14.3.1. Scanning for discontinuities oriented transverse to the weld will be carried out with the angle beam directed essentially parallel to the weld. For scanning of transverse defects, it should be considered to scan on the weld cap itself, which if necessary, must be ground flat. The search unit will be manipulated so that the angle beam energy passes through the required volumes of weld and adjacent base metal.
14.3.2. A transverse scan will be carried out on all welds scheduled for ultrasonic examination.
14.3.3. Nominal angles of reflection to achieve this are stated in table 2. The exception of the above will be when the search unit is scanning essentially as tangent over curved surfaces of 20” diameter or less.
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Table 2
45
60
70
0
8 - 25.4 mm
25.4 - 50.8 mm
50.8 - 65 mm
HSD
N/A
A(36 – 72)
A(72 – 92)
FSD
N/A
A(72 – 144)
A(144 – 184)
HSD
N/A
A(51 – 102)
A(102 – 130)
FSD
A(32 – 102)
A(102 – 203)
N/A
HSD
N/A
A(74 – 148)
A(148 – 190)
FSD
A(47 – 148)
N/A
N/A
HSD
N/A
N/A
A
FSD
A
A
A
Note) HSD: Half sonic distance / FSD: Full sonic distance, A: Applicable / N/A: Not applicable
15. Discont inui ty l ocalization and s ize evaluation
15.1. Discontinuities will be confirmed and located within the weld cross section by means of a probe manipulation to maximize the response obtained and to measure beam path lengths and distance from established reference points. Location reflectors may be aided by the use of trigonometry, electronic calculators and ultrasonic plotting slides. The use of these additional tools will not be mandatory.
15.2. Evaluation
15.2.1. The corrected primary gain (primary reference level + transfer correction) is to be increased by 6 dB for defect detection.
15.2.2. All discontinuities that produce reflectors at or grater than 20 % of DAC when searching at the increased gain level as above, are to be subject to defect size evaluation at non-increased gain level (i.e. with 6dB decrease). These imperfections shall be investigated to determine the shape, identity, and location.
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15.2.3. Dimensional evaluation of indication is made using either the 20 dB drop method or the half value drop method.
15.2.4. Also each indication producing an echo, which exceeds 50 % of the reference curve, is to be reported and its evaluated size as above checked for acceptability.
16. Post cleaning upon the completion of the examination, the surfaces shall be thoroughly cleaned by wiping with a suitable one as required to remove all traces of couplant.
17. Acceptance standards Acceptance criteria for piping welding shall be as per ASME B31.1 para. 344.6.2 and for steel structure welding shall be as per AWS D1.1 section 6 part C.
18. Defect m arking and examinatio n o f r epair
18.1. All areas deemed to be rejectable that require repairing, will be clearly and unambiguously marked up on the surface of the weld and the adjacent parent material with indelible metal markers.
18.2. The extent of examination will guarantee the satisfactory inspection of the entire cross sectional volume of weld and HAZ regardless of the extent of repair. The whole length of repair will be examined plus 50 mm from the repair weld deposit at the both ends where possible.
18.3. During repair examination, taking into consideration the nature, position and extent of the original defect and the position of new fusion faces created by the repair.
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19. Report ing
19.1. The report attached here after shall be reviewed and signed by TPA. 19.2. QC engineer shall maintain UT reports
20. Appendi ces
20.1. Appendix 1: Specific UT technique sheets 20.2. Appendix 2: Calibration report of Ultrasonic instrument 20.3. Appendix 3: Examination report 20.4. Appendix 4 Detail of Ultrasonic Examination Report
Page 23 of 34
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Ap pen di x 1: Specif ic UT t echni qu e sh eets Techni que 1 1. Joint Type: Butt Joint 2. Thickness (T): T 8~25.4mm similar thickness, plate and pipe (dia. > 20inch) 3. Probe a. 0°
4MHz
b. 60°
4MHz
c. 70°
4MHz
4. Range a. 0~50mm b. 0~100mm scanning with 0-1 skip c. 0~100mm scanning with 0-1/2 skip
5. Scanning Sensitivity a. Echo off first back reflection adjusted to 80% full screen height b. , c Echo off 2.4mm dia. Side drilled hole set to DAC + additional 6db + additional 2db transfer correction Note) Additional 6db to be removed for evaluation purpose
6. Sizing Method: Length #6db amplitude drop, depth and height (width) #20db drop 7. Scanning Patterns
National Iranian Gas Company
IGAT V Booster Gas Compressor Stations
OTC Document Title
Document No.
UT Procedure
PHASE
AREA
TRAIN/UNIT
DIS
DOC
SEQ
REV
SPY
3
0000
CM
PR
212
00
Page 25 of 34
Technique 2 1
Joint Type: Butt Joint
2
Thickness (T): T 25.4~50.8mm similar thickness, plate and pipe (dia. > 20inch)
3 Probe a. 0°
4MHz
b. 45°
4MHz
c. 60°
4MHz
d. 70°
2MHz
4 Range a. 0~50mm b. 0~150mm scanning with 0-1 skip c. 0~100mm scanning with 0-1 skip d. 0~150mm scanning with 0-1/2 skip
5 Scanning Sensitivity a. Echo off first back reflection adjusted to 80% full screen height b. , c, d Echo off 3.2mm dia. Side drilled hole set to DAC + additional 6db + additional transfer correction Note) Additional 6db to be removed for evaluation purpose
6 Sizing Method: Length #6db amplitude drop, depth and height (width) #20db drop 7
Scanning Patterns
National Iranian Gas Company
IGAT V Booster Gas Compressor Stations
OTC Document Title
Document No.
UT Procedure
PHASE
AREA
TRAIN/UNIT
DIS
DOC
SEQ
REV
SPY
3
0000
CM
PR
212
00
Page 26 of 34
Techni que 3 1
Joint Type: Butt Joint
2
Thickness (T): 50.8mm ~ 65mm
3 Probe a. 0°
2MHz
b. 45°
2MHz
c. 60°
2MHz
d. 70°
2MHz
4 Range a. 0~50mm b. 0~200mm scanning with 0-1 skip c. 0~150mm scanning with 0-1 skip d. 0~200mm scanning with 0-1/2 skip
5 Scanning Sensitivity a. Echo off first back reflection adjusted to 80% full screen height b. , c, d Echo off 4.8mm dia. Side drilled hole set to DAC + additional 6db + additional transfer correction Note) Additional 6db to be removed for evaluation purpose
6 Sizing Method: Length #6db amplitude drop, depth and height (width) #20db drop 7
Scanning Patterns
National Iranian Gas Company
IGAT V Booster Gas Compressor Stations
OTC Document Title
Document No.
UT Procedure
PHASE
AREA
TRAIN/UNIT
DIS
DOC
SEQ
REV
SPY
3
0000
CM
PR
212
00
Page 27 of 34
Techni que 4 1
Joint Type: Tee or Branch Joint
2
Thickness (T): T 8~25.4mm similar thickness, plate and pipe (dia. > 20inch)
3 Probe a. 0°
4MHz
b. 60°
4MHz
c. 70°
4MHz
4 Range a. 0~50mm b. 0~100mm scanning with 0-1 skip c. 0~100mm scanning with 0-1/2 skip
5 Scanning Sensitivity a. Echo off first back reflection adjusted to 80% full screen height b. , c Echo off 2.4mm dia. Side drilled hole set to DAC + additional 6db + additional 2db transfer correction Note) Additional 6db to be removed for evaluation purpose
6 Sizing Method: Length #6db amplitude drop, depth and height (width) #20db drop 7 Scanning Patterns
National Iranian Gas Company
IGAT V Booster Gas Compressor Stations
OTC Document Title
Document No.
UT Procedure
PHASE
AREA
TRAIN/UNIT
DIS
DOC
SEQ
REV
SPY
3
0000
CM
PR
212
00
Page 28 of 34
Techni que 5 1
Joint Type: Tee or Branch Joint
2 Thickness (T): 25.4mm ~ 50.8mm 3 Probe a. 0°
4MHz
b. 45°
4MHz
c. 60°
4MHz
d. 70°
2MHz
4 Range a. 0~50mm b. 0~150mm scanning with 0-1 skip c. 0~100mm scanning with 0-1 skip d. 0~150mm scanning with 0-1/2 skip
5 Scanning Sensitivity a. Echo off first back reflection adjusted to 80% full screen height b. , c, d Echo off 3.2mm dia. Side drilled hole set to DAC + additional 6db + additional transfer correction Note) Additional 6db to be removed for evaluation purpose
6 Sizing Method: Length #6db amplitude drop, depth and height (width) #20db drop 7
Scanning Patterns
National Iranian Gas Company
IGAT V Booster Gas Compressor Stations
OTC Document Title
Document No.
UT Procedure
PHASE
AREA
TRAIN/UNIT
DIS
DOC
SEQ
REV
SPY
3
0000
CM
PR
212
00
Page 29 of 34
Techni que 6 1
Joint Type: Tee or Branch Joint
2
Thickness (T): 50.8mm ~ 65mm
3 Probe a. 0°
2MHz
b. 45°
2MHz
c. 60°
2MHz
d. 70°
2MHz
4 Range a. 0~50mm b. 0~200mm scanning with 0-1 skip c. 0~150mm scanning with 0-1 skip d. 0~200mm scanning with 0-1/2 skip
5 Scanning Sensitivity a. Echo off first back reflection adjusted to 80% full screen height b. , c, d Echo off 4.8mm dia. Side drilled hole set to DAC + additional 6db + additional transfer correction Note) Additional 6db to be removed for evaluation purpose
6 Sizing Method: Length #6db amplitude drop, depth and height (width) #20db drop 7
Scanning Patterns
National Iranian Gas Company
IGAT V Booster Gas Compressor Stations
OTC Document Title
Document No.
UT Procedure
PHASE
AREA
TRAIN/UNIT
DIS
DOC
SEQ
REV
SPY
3
0000
CM
PR
212
00
Page 30 of 34
Techni que 8 1
Joint Type: Butt Joint
2
Thickness (T): T 8~25.4mm similar thickness, plate and pipe (dia. ≤ 20inch)
3 Probe a. 0°
4MHz
b. 60°
4MHz
c. 70°
4MHz
4 Range a. 0~50mm b. 0~100mm scanning with 0-1 skip c. 0~100mm scanning with 0-1/2 skip
5 Scanning Sensitivity a. Echo off first back reflection adjusted to 80% full screen height b. , c Echo off 2.4mm dia. Side drilled hole set to DAC + additional 6db + additional 2db transfer correction Note) Additional 6db to be removed for evaluation purpose
6 Sizing Method: Length #6db amplitude drop, depth and height (width) #20db drop 7
Scanning Patterns
National Iranian Gas Company
IGAT V Booster Gas Compressor Stations
OTC Document Title
Document No.
UT Procedure
PHASE
AREA
TRAIN/UNIT
DIS
DOC
SEQ
REV
SPY
3
0000
CM
PR
212
00
Page 31 of 34
Technique 8 1
Joint Type: Butt Joint
2
Thickness (T): T 44.45mm similar thickness, plate and pipe (dia. = 20inch)
3 Probe a. 0°
4MHz
b. 45°
4MHz
c. 60°
4MHz
d. 70°
2MHz
4 Range a. 0~50mm b. 0~150mm scanning with 0-1 skip c. 0~100mm scanning with 0-1 skip d. 0~150mm scanning with 0-1/2 skip
5 Scanning Sensitivity a. Echo off first back reflection adjusted to 80% full screen height b. , c, d Echo off 3.2mm dia. Side drilled hole set to DAC + additional 6db + additional transfer correction Note) Additional 6db to be removed for evaluation purpose
6 Sizing Method: Length #6db amplitude drop, depth and height (width) #20db drop 7
Scanning Patterns
National Iranian Gas Company
IGAT V Booster Gas Compressor Stations
OTC Document Title
Document No.
UT Procedure
PHASE
AREA
TRAIN/UNIT
DIS
DOC
SEQ
REV
SPY
3
0000
CM
PR
212
00
Page 32 of 34
Ap pen di x 2 Cal ib rat io n r epo rt of ULTRASONIC ins tr um ent INSTRUMENT TYPE:
CALIBRATION RECORD UNIT
I. D. No.
:
Sr. No.
:
Type
Marker
Frequency
Size
TRANSDUCER Sr. No.
2. SCREEN HEIGHT LINEARITY 100%FSH ---------------%FSH 90%FSH ---------------%FSH 80%FSH ---------------%FSH 70%FSH ---------------%FSH 60%FSH ---------------%FSH
Screen Height Linearity
50%FSH 40%FSH 30%FSH 20%FSH
---------------%FSH ---------------%FSH ---------------%FSH ---------------%FSH
3. AMPLITUDE CONTROL LINEARITY 80%FSH-6dB ----------------------%FSH (32-48) 80%FSH-12dB ----------------------%FSH (16-24) 40%FSH-6dB ----------------------%FSH (64-96) 20%FSH-12dB ----------------------%FSH (64-95)
Amplitude Control Linearity 4. HORIZONTAL LINERARITY 1) Range-100mm Liner scale
(a)25
(b)50
(c)75
(d)100
Echo position
(a)
(b)
(c)
(d)
(a)25 (a)
(b)50 (b)
(c)75 (c)
(d)100 (d)
2) Range-200mm Liner scale Echo position
Examined by
Level
Date
Approved by
(e)125 (e)
(f)150 (f)
Level
(g)175 (g)
(h)200 (h)
Date
FORM CM-PR-212-01 Rev. 00
National Iranian Gas Company
IGAT V Booster Gas Compressor Stations
OTC Document Title
UT Procedure
Document No. PHASE
AREA
TRAIN/UNIT
DIS
DOC
SEQ
REV
SPY
3
0000
CM
PR
212
00
Page 33 of 34
Ap pen di x 3 Ul tr aso ni c Ex ami nat io n Rep or t ITP NO.
FIELD INSPECTION REPORT
:
REPORT NO. : DATE
INSPECTION TYPE:
:
WORK NO.: ITEM NO.
ULTRASONIC EXAMINATION
:
LOCATION : SIGNATURE
INSPECTION NOTICE NO.
:
COMPANY'S INSPECTOR
:
CONTRACTOR INSPECTOR
COMPANY /
1
CONTRACTOR
/
/
SUBCONTR.
/
/
/
:
SUBCONTRACTOR'S INSPECTOR : PROCEDURE METHOD ACCEPTANCE CRITERIA
: :
MATERIAL
:
THICKNESS:
METHOD
:
PROBE SIZE:
MEDIUM ANGLE:
:
FREQUENCY:
MAKER & TYPE OF MACHINE: DWG N0.
JOINT NO.
WELDER NO.
RESULT
ACC
REP
C-O
ABBREVIATIONS ACC
: ACCEPT
EP
: EXCESS PENETRATION
REP
: REPAIR
IP
: INCOMPLETED PENETRATION
C-O
: CUT-OUT
LF
: LACK OF FUSION
C
: CRACK
S
P
: POROSITY
ND
: SLAG INCLUSION : NO DEFECT
* SEE ATTACHED SHEET (DETAILED ULTRASONIC EXAMINATION RECORD) 1- To be signed if Accepted by all parties LEGEND: ACC.: ACCEPT REJ.: REJECT
N/A: Not Applicable
FORM:QA-QA-51-06
1/2
Rev. 01