C1071 - Ultrasonic Exam of Pipeline Welds

Section: C1071Title: Ultrasonic Examination of Pipeline Welds

CONSTRUCTION STANDARDS Created: 2009-11-01

Table of Contents

1. Scope.................................................................................................................................................. 12. Referenced Codes and Standards......................................................................................................13. Definitions........................................................................................................................................... 14. General............................................................................................................................................... 25. Visual Observation.............................................................................................................................. 36. Ultrasonic Inspection........................................................................................................................... 37. System Set-Up.................................................................................................................................... 68. Calibration Qualification...................................................................................................................... 89. Field Inspection................................................................................................................................... 910. System Verification............................................................................................................................. 911. Scanning Sensitivity.......................................................................................................................... 1012. Re-Inspection.................................................................................................................................... 1013. Transducer Performance.................................................................................................................. 1114. Evaluation of Indications...................................................................................................................1115. Weld Inspection Record and Reports................................................................................................1216. Additional Requirements...................................................................................................................1317. Records............................................................................................................................................. 13Appendix A - Specification for Manual Ultrasonic Inspection of Pipeline Welds........................................15

1. Scope

This specification establishes minimum requirements for ultrasonic examination of GMAW and Manual Weld procedure qualification welds, performance qualification welds, production welds, and repair welds completed for the Company. Notwithstanding the requirements set forth herein, ultrasonic examination shall conform to the requirements of the most recent approved edition of 49 CFR 192 and API 1104.

2. Referenced Codes and Standards

In addition to this specification, the most recent edition of the following documents shall apply to the work.

49 CFR 192, “Transmission of Natural And Other Gas By Pipeline” API 1104-19th Edition, “Welding of Pipelines and Related Facilities” API 1104-20th Edition, Addendum to API Standard “Welding of Pipelines and Related Facilities” –

Revision of Appendix A – Alternative Acceptance Standards for Girth Welds SNT-TC-1A, “Personnel Qualification and Certification in Nondestructive Testing” ASTM E164, “Practice for Ultrasonic Contact Examination of Welds” ASTM E317, “Practice for Evaluating Performance Characteristics of Ultrasonic Pulse-Echo

Testing Systems Without the Use of Electronic Measurement Instruments” ASTM E494, “Practice for Measuring Ultrasonic Velocity in Materials” ASTM E1316 “Standard Terminology for Non Destructive Examinations” ASME Section V, “Nondestructive Examination” BS 7706 1993 Calibration and setting up of the ultrasonic time of flight diffraction technique for

the detection, location and sizing of flaws.

3. Definitions

Definitions contained in ASME Section V, Article 5, Mandatory Appendix III apply to this specification.

Company: The term “Company” as used in this specification shall mean Kinder Morgan Incorporated (KMI) including its engineering agencies, inspectors, and other authorized representatives.

Contractor: The term “Contractor” as used in this specification shall mean the ultrasonic inspection contractor engaged by the Construction Contractor in work covered by this specification.

Highlighting indicates revisions made as of the date on this standard. Page 1 of 18



Operator(s): The term “Operator(s)” as used in this specification or in any attached specification sheet shall mean operators of ultrasonic equipment. Ultrasonic operators shall be qualified and certified in conformance with the requirements of Level II ASNT Recommended Practice SNT-TC-1A (at a minimum) and shall submit their records of certification to the Company Representative. Operator performance will be observed during welder tests. The operator must demonstrate an acceptable level of proficiency when operating the ultrasonic inspection equipment and interpret the inspection data in accordance with API 1104 requirements. The designated spread supervisor shall be responsible for the entire crew. The Company shall approve operators before the start of any work.

Pipeline: The term “pipeline” as used in this specification means a pipeline (including laterals, branch connections, extensions, compressors, pumps, and related facilities) for the transmission of natural gas.

4. General

4.1. General Conditions

4.1.1. The Company shall have the right to nondestructively examine any weld while the weld is being made and after the weld has been completed. The examination shall be used to assess conformance with 49 CFR 192, API 1104, and Section 14 - Evaluation of Indications, of this specification. The Company shall also have the right to order the removal of any weld for the purpose of destructive tests. The Company is the final authority for the acceptance of welds.

4.1.2. The Contractor shall provide ultrasonic inspection service for all automatic girth welds and any other welds designated by the Company during the construction of a pipeline or facility.

4.1.3. Pulse-echo and/or pitch-catch transmission techniques with focused probes shall be used with a minimum of A-scan and B-scan presentations and a fully automatic recording system to indicate accurately circumferential location, circumferential length, through-thickness location, and through-thickness height of defects as well as the continuity of acoustic coupling. The instrument shall be capable of both pulse-echo and pitch-catch operating modes.

4.1.4. The Contractor shall provide the Company with:

A hard-copy recording of the inspection The judgment of acceptability of each weld examined The recordings of the calibration standard scans The electronic version of welds with applicable viewing software

4.1.5. The inspection shall use an automatic ultrasonic system capable of maintaining production rates established by the Pipeline Construction Contractor. The system shall be self-contained, have an independent power supply, and be mounted on an all-terrain vehicle. Manual ultrasonic inspections may also be required for weld repairs or other welds as directed by the Company.

4.1.6. The principle mainline welding technique shall be Automatic Gas Metal Arc Welding. Manual welds and repair welds will be completed by Shielded Metal Arc Welding, MIG and/or Flux-Core Welding combinations.

4.1.7. Automatic ultrasonic testing (AUT) tie-in rigs may be used to inspect Manual field welds and repairs if the AUT Manual Weld procedure has been qualified prior to field inspection commencement and as a minimum has met the requirements of this specification and API 1104.

4.1.8. The Contractor shall designate a Job Supervisor responsible for the conduct and performance of all ultrasonic personnel and for maintaining the reliability of all equipment and supplies. The Job Supervisor shall work closely with the Company’s




Senior Welding Inspector and Field Auditor in the documentation of completed inspections, and shall be responsible for all reports, interpretations, and evaluation. The Job Supervisor shall ensure that interpretations are consistent, informative, and in accordance with API 1104. The Job Supervisor shall be capable of technical support for automatic UT operations.

4.1.9. Unless otherwise directed by the Company, Contractor shall have all necessary equipment and personnel on site to maintain a production rate that ensures all welds completed before 4:30 PM on any working day are inspected, interpreted, and included in the Ultrasonic Inspection Report for that working day.

4.1.10. Contractor shall have all necessary spare equipment to ensure continuance of the work without interruption or delays. This will be routinely inspected by the Company Field Auditor. Nonconformance reports shall be reported to the Pipeline Contractor and NDE Contractor immediately.

5. Visual Observation

GMAW Welds shall be scribed when ever possible to ensure that the search unit array is adjusted to the same distance from the weld centerline to duplicate the examination of the reference standard. Longitudinal or helical weld seams shall be ground flush and weld spatter shall be removed prior to AUT Mainline arrival for all weld processes to a minimum distance as defined in the contractor’s AUT procedure.

Note: Tie-Ins may be excepted, but require centered root geometry readings in the AUT strip chart.

Any weld impediments such as Grease Markings within 6” of weld, mud, longseams etc observed during setup and scanning that effect the AUT scan integrity shall be reported to the Company Representative and rectified.

6. Ultrasonic Inspection

6.1. Introduction

6.1.1. Mainline girth welds made by automatic welding methods and Manual Tie-in welds (if applicable) shall be fully examined by an automatic ultrasonic inspection system for 100% of the circumference, in conformance with API 1104. The inspection system shall be capable of locating and accurately accessing the through-wall height and circumferential length of defects, in a manner that permits the use of the acceptance criteria defined by the Company in conformance with API 1104, 20th Edition – Appended Appendix A. SMAW welds shall be inspected in conformance with Company Construction Standard C1066 Weld Inspections and Testing, C1070 – Non- Destructive Examination Requirements and API 1104, 19th Edition - Section 9.6 (workmanship) criteria.

6.1.2. To ensure the consistent production of high-quality ultrasonic inspections, ultrasonic personnel shall be qualified in conformance with Subsection 6.2 - Operator Qualification (follows), and ultrasonic procedures shall be qualified in conformance with Subsection 6.3 - Procedure Qualification (below).

6.2. Operator Qualification

6.2.1. A nationally certified ASNT Level III in the ultrasonic method shall develop the application technique and prepare and approve the testing procedure. The procedure shall be submitted to the Company for review and approval before production welding.

6.2.2. Ultrasonic operators shall be qualified and certified by examination in conformance with Level II requirements of the most recent edition of ASNT Recommended Practice SNT-TC-1A, and shall submit their records of certification to the Company Representative. Additionally, operators shall have received a minimum of 40 hours of training on




automatic testing, including practical and theoretical aspects pertinent to the equipment and configurations to be examined. This training shall be documented.

6.2.3. Before the initiation of any work, the Company shall approve ultrasonic operators and the automatic ultrasonic inspection system. AUT systems shall qualify for this pipeline inspection by demonstrating its ability to detect and characterize typical weld indications and determine the acceptance in conformance with the criteria of API 1104, Appendix A and/or Section 9. The characterization shall include the ability to locate the indication within the weld and determine through-wall height. The company shall provide qualification test pieces consisting of one or more pipe samples with defects. The AUT qualification test shall be administered and witnessed by the Company during weld production welding.

6.2.4. Ultrasonic operators shall qualify for manual inspection of repaired welds using qualification test pieces containing defects in repaired welds. Operators shall demonstrate ability to detect and characterize typical indications - and determine their acceptance in conformance with API 1104, Section 9, and shall be approved by the Company.

6.2.5. Only qualified ASNT level II (or equivalent) automated ultrasonic and manual ultrasonic operators in conformance with this specification shall be permitted to inspect welds and mark out defect areas using the ultrasonic technique.

6.3. Procedure Qualification

6.3.1. Ultrasonic inspection shall be performed in conformance with a documented, detailed procedure approved by the Company. Approved procedures shall include the applicable information stated in this specification, information required by API 1104 Section 11, information stated in ASME Section V, Article 5, Paragraph T-522, and a description of the methodology used to investigate indications.

6.3.2. The Contractor shall demonstrate the effectiveness of proposed procedures before being approved for use in the performance of the Work. The Contractor shall not use a procedure in the performance of the work that has not been approved by the Company. Qualifying inspections shall be produced under site conditions and in the presence of the Company Representative for each proposed procedure and/or technique. Such procedure acceptance testing shall be performed using Contractor weld procedure or welder qualification test welds. The qualification process shall occur before the commencement of production welding.

6.3.3. The Contractor shall provide an automatic ultrasonic inspection procedure that allows for full volumetric examination of a weld in a single pass, from both sides of the weld. The procedure shall allow for edge misalignment and weld shrinkage, and shall provide for characterization of defect location in the weld thickness direction, through-wall defect height, and circumferential defect length and depth. Exception: AUT procedures for tie-ins welds of unequal wall thickness may be inspected with multiple AUT scans or passes when qualified. Defect location and sizing shall permit use of Company-defined acceptance criteria based on the Engineering Critical Assessment provisions of API 1104, Appendix A (GMAW only). It shall include, but is not limited to, the following requirements:

An automatic variable speed scanner mounted on automatic welding bands or other tracking devices

An encoder capable of accurately indicating any defect location within the girth weld

Independently loaded ultrasonic transducers mounted in an array that provides independent inspection of the weld from both sides

Provisions for adjustments and maintaining the alignment of the transducers Provisions for recording the continuity of the coupling Provisions for ensuring the mechanical reliability of the equipment




A technique summary sheet stating beam angles, wave types, transducer frequencies, beam size profiles, including sketches for each geometry to be examined and other relevant information

A record of analog and/or digital signals from the multiple channels to a common distance of rotation

Provisions for a permanent copy of scans in an easily-interpreted format to meet archival and audit needs

Construction and accuracy details of the calibration piece Calibration procedures to be used in the field Calibration checks that shall be established and verified on a time or weld cycle

defined by the company, with system performance between calibration checks continually monitored for degradation

6.3.4. A minimum of two welds per welding procedure prepared from production pipe containing defects and acceptable imperfections shall be examined. The welds shall be radiographed in accordance with Company Construction Standards C1066 - Weld Inspections and Testing and Construction Standard C1070 - Non-Destructive Examination Requirements. The UT procedure shall be applied within the detailed temperature ranges and the results documented and compared with the radiographs. Differences in detection results shall be noted and documented. At the discretion of the Company, destructive testing of the weld sample may be performed to confirm results.

6.3.5. The test details, including a notation of all the defects (along with a hard-copy recording of the inspection) shall be submitted to the Company for approval. The Company shall notify the Contractor of its approval of each procedure and/or technique validated. Upon approval from the Company, the procedure becomes a mandatory requirement and changes are only permitted with further approval from the Company.

6.3.6. The Contractor shall prepare a procedure for manual inspection of manually repaired welds. ASTM E164 and API 1104, Section 11.4 shall be used as guidance in developing the procedure. Appendix A of this document provides some details of the required contents of this procedure.

6.4. System Performance

The Contractor shall successfully demonstrate system performance using project pipe. The demonstration shall include integration of hardware, software, and personnel in a manner that permits reliable detection and accurate sizing weld imperfections in conformance with API 1104, Appendix A. The Contractor shall demonstrate the accuracy of the system for accessing through-wall height imperfections. The accuracy shall be verified by destructive testing results. Accuracy shall be demonstrated on the thinnest and the thickest wall thickness of project pipe. The Company shall be sole judge of system performance for the intended use.

6.5. Calibration

6.5.1. The calibration block and included reflectors shall provide the required sizing accuracy, the ability to provide defect location in the weld, and the determination of surface interaction per API 1104, Appendix A.

6.5.2. Calibration standards shall be used to qualify the inspection system and to monitor system performance on an ongoing basis. Calibration standards shall be manufactured for a section of project-specific pipe supplied by the Company, and the Company shall provide the Contractor with geometric details of weld bevels intended for the project. The Contractor shall submit a calibration standard design to the Company for approval before manufacture. No design changes shall be made without prior approval from the Company. Calibration standard reflector dimensions and locations within the standard shall be certified with instruments traceable to a national standard(e.g. NIST or equivalent). The block shall be uniquely identified and traceable. The unique number, wall thickness, diameter, steel manufacturer, shear wave acoustic velocity in the direction of testing, temperature, and velocity measurement shall be




documented. The acoustic velocity shall be measured in conformance with ASTM E494 or equivalent approved by the Company. The velocity results shall be documented.

6.5.3. Calibration reflectors shall be flat bottom holes (FBH) for fusion (planar) defects. Surface notches shall be used in line with the anticipated fusion line. These notches shall be N10 notches as defined in API 1104 Section 11. Root notches shall be of the same angle as anticipated fusion line of the root of the weld examined. Porosity reflectors shall be flat-bottomed holes; other informational reflectors may be used but must not interfere with calibration reflectors. A through-wall hole or notch should be machined in the center of the block or ends. Calibrations for primary sensitivity shall use flat bottom holes. Time of flight diffraction (TOFD) EDM notches for ID and OD shall be used. For root calibration, a root notch may be used. Reflectors for planar indications shall be located on the anticipated fusion line.

For manual ultrasonic inspection of shielded metal arc welds, N10 notches shall be milled on the outside surface and inside surface of the block.

6.5.4. Machining tolerances for all calibration parameters shall be less than or equal to the following:

6.5.4.1. Hole diameter ± 0.2 mm

6.5.4.2. Flatness of FBH ± 0.1 mm

6.5.4.3. Angles ± 1 degree

6.5.4.4. Notch Depth ± 0.1 mm

6.5.4.5. Notch Length ± 10%

6.5.4.6. Center location ± 0.1 mm

6.5.4.7. Hole Depth ± 0.2 mm

6.5.5. Project pipe will be available for procedure development and calibration block design before weld procedure qualification or AUT qualification commences.

6.6. Ultrasonic Equipment

The scanning system shall provide enough inspection channels to ensure the complete volumetric examination of the weld through thickness in one circumferential scan, including transverse scans. The instrument shall provide a linear “A” scan presentation for each channel selected. A selectable “A” scan presentation shall be available during scanning. The inspection channels shall allow assessment of the full volume of the weld scanned, and all defects present detected, located, and sized in the through-wall direction. Instrument linearity shall be determined in conformance with ASTM E317, within 3 months of the intended end use date. A Company-approved form shall be used to document instrument linearity verification. The Contractor shall retain a current copy of the calibration certificate at the worksite. Each transducer’s performance shall be documented before use on a Contractor-developed form approved by the Company.

6.6.1. The transducer array design shall be specific to the project where the inspection is to be performed.

6.6.2. All search units shall be contoured to match the curvature of the pipe surface.

7. System Set-Up

7.1. Transducer Positioning and Primary Reference Sensitivity

7.1.1. Primary Reference Level

The system shall be optimized for field inspection using the calibration standard established in Subsection 6.5 – Calibration, in this specification. Each transducer shall




be positioned at its operating distance away for the simulated weld centerline on the calibrated standard and adjusted to provide a peak signal from its target reference reflector in the transducer’s inspection zone. The peak signal response shall be adjusted to ideally 80% of the full screen height for each channel. This gain level shall be the primary reference for that transducer. The primary reference level shall be recorded in the procedure (see Subsection 6.3 - Procedure Qualification (above)). Variation and corrective actions to maintain calibration shall be recorded on a Company pre-approved form. Whereas for intitial standardization, the channels shall be adusted to ideally 80% full screen height, a satisfactory standardization during inspection may indicate 70 to 99% full screen height. The noise shall be at least 20dB weaker than the signal at the target path, and electronic noise shall be 40 dB weaker. The transducer operating distance relative to a marked index point shall also be recorded on the form.

7.1.2. Gate Settings

Using the calibrated standard, each detection gate shall be set to cover a sound path which starts at least 1 mm before the weld heat-affected zone or 3 mm before the weld preparation, whichever is greater, and ends at least 1 mm past the weld centerline. The gate start position and gate length (with respect to the weld preparation for each detection channel) shall be recorded in the procedure.

7.1.3. Gate Recording Threshold

The recording threshold of each detection channel shall be equivalent to the requirements of API 1104 Specific targets for porosity detection should be determined by a NDT level III in the ultrasonic method and shall be validated at AUT qualification.

7.1.3.1. AUT system qualification, defect assessment, and verification trials shall be performed during and after Weld Procedure Qualifications.

7.1.3.2. AUT operators/scanner technicians shall notify Visual Company Inspectors of any suspect visual calls noted on the outer surface or inner surface. The area will be noted on the NDE Daily Sheet as a visual inspection request (VIR) with applicable area and the visual inspector will measure and confirm the area with mechanical measurement. The visual inspector shall accept or reject the visual indication in the applicable weld area and sign the report.

7.1.4. Chart Recorder Set-Up

Channel output signals shall be arranged on the AUT strip chart record in an approved order. In addition, time delays shall be applied to the signals to compensate for different transducers circumferential positions relative to the circumferential zero point and subsequent distance markers. Details of the delays applied and the chart arrangement shall be recorded in the procedure. Variations and corrective actions to maintain calibration shall be recorded on a Company pre-approved form.

7.1.5. Circumferential Scanning Velocity

Where Wc is the narrowest -6dB beam width at the applicable operating distance(s) of all transducers in conformance with the design requirements, and PRF is the pulse repetition frequency per transducer, the circumferential scanning velocity, Vc shall be limited by the equation:

7.1.6. Circumferential Scanning Direction


Vc < Wc PRF 3



The circumferential scanning direction shall be clockwise when viewed from the upstream side of the pipe in the direction of construction. Drag sections and other instances when the pipe is scanned in reverse shall be documented “REVERSE SCAN” on the weld chart and NDE Weld Form.

7.2. Transfer Value

A comparison of transfer value shall be made between the calibration block and the pipe weld to be tested. The value shall be taken through the weld and the result shall be added or subtracted, as applicable to or from the reference level. This task shall be performed at the weld procedure qualification and or prior to any field work. The result of the transfer value shall be documented with the weld identification (Weld ID) and probes used.

7.3. Operating Log

A log shall be kept of adjustments, changes to measurements, dB changes, or other changes from those stated in the weld specific technique (instruction) setup. Major changes shall be documented (e.g. wedge change outs, transducer changes, dB calibration settings). Essential variables include: temperature, probe angles, probe frequency, probe offsets and channels per weld.

8. Calibration Qualification

8.1. Detection Channels

8.1.1. With the system optimized, the calibration standard shall be scanned in the multiplexed mode. The recording medium should indicate 70-99% (within specified tolerance) of full screen height signals from each calibration reflector recorded in their correct position assigned on the recorder chart. The actual calibration block reflector spacing shall be compared to the AUT recorded reflectors and should have a circumferential positional accuracy within +/-2mm (relative to each other), when approved by the Company, shall be used as the inspection quality standard to which subsequently-produced calibration charts shall be judged for acceptability. Due care shall be taken with respect to the start / finish distance, the circumferential reading shall be within ± 1 cm of actual measured pipe circumference. Also the start position shall be clearly marked on the pipe at approximately 12:00 with a permanent marker and the probe array lead transducer shall be started at that location.

8.1.2. Calibrations shall be performed at the same scanning speed as the weld examination. As this is a dynamic scan, no stop/starting or rocking is allowed.

8.1.3. Calibrations will provide sufficient but not saturated overtrace weld coverage to adjacent zonal areas. The adjacent inspection zone coverage from primary target location to adjacent reflector target separation should provide a response no less than 14dB but greater than 6dB.

8.2. Coupling Monitor Channels

8.2.1. When using separate coupling monitors, amplifier gain shall be adjusted (when on the calibration standard) to produce a maximum echo height of 80% from the full “vee” path. When in through transmission mode, amplifier gain shall be adjusted to produce a maximum echo height of 80% FSH and up to a maximum of +12dB transmitted signal. The recording gate threshold level shall be a minimum of 20% of full screen height to a maximum 80% of full screen height.

8.2.2. The re-inspection of the calibration standard (with its surface wiped dry) shall produce a record showing a lack of coupling (i.e., absence of recording signal).

8.3. Measurement to Assess Transducer Wear

8.3.1. Transducers shall be certified as meeting the performance requirements of British Electrical Supply Industry Standard ESI 98-2.




8.3.2. The Contractor shall provide baseline height measurement for the transducer case before the start of field weld examinations. An accurate (± 0.1 mm) measurement shall be made of the case height at each of the corners of each transducer. These measurements shall be recorded on a Company-approved form for a comparison of periodic measurements taken throughout the project (to assess transducer wear). The frequency of checks shall be defined in the AUT procedure.

9. Field Inspection

9.1. Weld Marking

9.1.1. The Contractor shall permanently identify each weld with a unique weld identification (Weld ID) following the Weld ID system provided by the Company.

9.1.2. The Weld ID shall be positioned on the pipe surface on the work side of the pipe and on the downstream side of the weld in a manner approved by the Company Representative.

9.1.3. Applied using a white or black permanent marker, Weld IDs shall be large enough to be clearly identified from work-side of the Right-of-Way (ROW) (e.g. a distance of 3 meters). The Weld ID shall be located at a distance from the weld that ensures that the ID shall not be covered or obscured by other operations and on the pipe such that the Weld ID is visible while viewing the pipe when laid in the ditch.

9.2. Coating Cutback

Transducers shall not be allowed to run on coating (partially or fully, in any way) during production weld inspection. Coating cutback distances must be defined in the AUT procedure for Manual and GMAW inspections.

9.3. Surface Condition

The scanning surface shall be free of weld spatter and other irregularities that could interfere with the movement of the transducers, the coupling, or the transmission of acoustic energy into the material. Refer to Section 5.0 – Visual Observation.

9.4. Reference Line

9.4.1. Before welding, the Contractor wherever possible shall scribe a reference line on the pipe surface on the intended band side of pipe - at a known distance from the weld centerline - with an accuracy of ± 0.5 mm from the centerline of the weld preparation.

9.4.2. The reference line shall be used to ensure that the band is adjusted to the same distance from the centerline as to replicate the calibration standard. The tolerance to ideal positioning shall not exceed ± 0.5 mm. The 12 o’clock position (not 1 o’clock or 2 o’clock) shall also be clearly marked on the pipe to indicate the start position (0 cm) position of the scan.

10.System Verification

10.1. Sensitivity

10.1.1. The calibration standard shall be used daily:

Before beginning pipe weld inspections After repairs Thereafter at intervals not exceeding 1 hour or 10 welds, whichever comes first At the conclusion of the shift

10.1.2. The percent of screen reflections from the calibration standard shall be recorded on a Company-approved Sensitivity Record Form. Any gain changes required to maintain required sensitivity during the shift as per Section 7.0 - System Set-Up (in this specification) shall be recorded on the same Company-approved form. The hard-copy




record of the calibration standard scan shall be included sequentially with the weld inspection charts. The last weld inspected - and the time when it was performed, shall appear on each calibration chart. These charts shall be made available to the Company when requested.

10.2. Circumferential Position Accuracy

The position accuracy of chart distance markers shall be validated twice during each working shift. The scanner shall travel from the zero position with the scanning frame coincident with the pipe. At all o’clock positions, the index marks on the scanning frame and the pipe must be aligned. The chart shall then be compared to circumferential distance measured with a diameter tape. Chart accuracy shall be within ±1 cm or better. Results shall be recorded on a Company-approved form.

10.3. Transducer Surface Position Accuracy

Shifts in the refracted angle - resulting from the change in velocity within the wedge line materials or pipe due to temperature, strain, or compositional variances - shall be corrected for by adjustment of the transducer surface position. Care shall be taken to ensure that the gate start, length, and height positions are still set following any such adjustment with each calibration performed.

10.4. Temperature Control

10.4.1. It shall be the NDE Contractor’s responsibility to maintain the AUT system temperature differential. The temperature differences between the probes on the welds (to be inspected) and on the calibration block shall be monitored using a thermocouple mounted in a probe housing of the probe array. The temperature shall be monitored using a thermocouple and recording device. The temperature shall be recorded on all the hard-copy printouts. These steps are mandatory unless an alternative procedure can be validated before field inspection to ensure inspection overlap coverage is not compromised.

10.4.2. For testing at temperature extremes in hot or cold conditions, the calibration block may require heating or cooling to keep the array within a 18°F (10° Celsius) variance when completing ‘calibration in’, weld scan, and ‘calibration out’ cycles. This shall be documented on all hard-copy calibration and weld printouts.

11. Scanning Sensitivity

The calibration standard shall be used to verify scanning sensitivity:

At the start of each shift Thereafter at intervals not exceeding 1 hour or 10 welds, whichever comes first Weld Repair calls At the conclusion of each shift Change out of AUT essential variables – Section 7.3 – Operating Log At any other intervals defined by the Company

At a minimum, the first 50 production welds shall have calibrations both before and after welding to ‘wear in’ the system (unless Contractor procedure is more stringent). Records for each calibration standard scan shall be included, sequentially, with the weld inspection data. During production weld inspection, at the Company’s discretion, the system may be operated at a higher gain to ensure detection of defects and to compensate for differences in coupling efficiencies between the calibration standard and the production pipe (this will be established at the welder qualifications and then implemented into the AUT procedure). An acceptable calibration during production indicates values between 70-99% FSH(unless otherwise approved). Calibration outside of this range shall require re-calibration of the system unless qualified or compensated for during AUT qualifications.

12.Re-Inspection




12.1. Sensitivity

Welds examined at a sensitivity varying more than the scanning sensitivity as defined in Section 11 - Scanning Sensitivity , shall be re-inspected or reevaluated at acceptable procedure defined settings from last acceptable calibration point.

12.2. Coupling Losses

If not covered by TOFD, welds examined with coupling losses in more than 1 adjacent channel shall be manually scanned with MUT to verify that no defects in the couplant loss area exist, and/or to identify why the couplant loss condition exists (e.g. mud on the pipe, excessive hi-lo, or an actual defect). Individual losses of couplant shall not exceed 12mm.

12.3. Scanner Slippage

Scans shall not be acceptable where any slippage occurs. Where slippage is noted, the scanner shall be adjusted to correct the problem and the scan shall be repeated, with no additional compensation to the Contractor.

12.4. Defect

A weld originally called for repair by automatic ultrasonic inspection shall be re-tested by manual ultrasonic testing per Appendix A (of C1071) after the repair has been completed.

12.5. Temperature Variance

Welds examined with wedge temperature difference greater than ±18°F (+10° Celsius) from the temperature used for calibration shall be re-tested, unless qualified before field work.

12.6. Other Conditions

When conditions exist where data collection is impaired or data is lost, the weld shall be re-tested. In addition, 100% of all welds shall be inspected.

13.Transducer Performance

Transducers shall be examined for wear as per Subsection 8.3 - Measurement to Assess Transducer Wear (in this specification), whenever wear is apparent, but not greater than at an interval of 500 welds. The signal-to-noise value for each transducer shall also be compared to the value obtained in conformance with Section 7 - System Set-Up - at the start of the project. Case heights and the signal-to-noise value for each transducer shall be recorded on Company-approved forms.

13.1. Transducer Re-surfacing/Replacement

The transducer contact face shall be re-surfaced, or the transducers replaced to correct any of the following:

13.1.1. Beam angle changes of ±1.5 degrees for angles less than 45 degrees or ± 2 degrees for angles greater than 45 degrees.

13.1.2. Squint angles exceeding 1.5 degrees for single crystal transducers and 2 degrees for twin crystal transducers.

13.1.3. A signal-to-noise reading 6 dB less than the value obtained at the start of the project.

13.1.4. Scores in the transducer wear face, which exceed 0.5 mm in depth.

13.1.5. Balance from corresponding upstream and downstream channels shall not differ by more than 6dB.

14.Evaluation of Indications

14.1. GMAW Welds

All identical wall GMAW welds will be inspected to API 1104 Appendix A “Alternative Acceptance Criteria”. Indications from GMAW weld imperfections shall be evaluated according




to defect acceptance criteria defined by the Company using an Engineering Critical Assessment carried out according to API 1104, Appendix A. Evaluations shall be completed immediately after inspection of the weld. Failure to meet the API 1104 – Appendix A “Alternative Acceptance Criteria” requires Manual UT.

14.2. Manual UT Inspection on Repairs

14.2.1. To verify that the initial GMAW defect has been completely removed.

14.2.2. To verify that the Manual repair conforms to API 1104 19th Edition Section 9.6. See Appendix A - Specification for Manual Ultrasonic Inspection of Pipeline Welds of this document for more details.

14.2.3. All welds evaluated to API 1104 19th Edition Section 9.6 with individual indications with a vertical height (through-wall) dimension determined to be greater than one quarter of the wall thickness and multiple indications at the same circumferential location with a summed vertical height (through-wall) dimension exceeding one half the wall thickness shall be considered defects.

15.Weld Inspection Record and Reports

15.1. Weld Inspection Record

The Weld Inspection Record shall consist of a complete strip chart type record showing the reference point, the direction of scanning, the Weld ID, date and time of inspection, and the Operator signature. The search unit number in each channel shall also be recorded. The Company may approve alternate record formats.

15.2. Interpretation of Weld Inspection Record

Areas on the AUT chart with a corresponding pulse echo response (exceeding evaluation threshold) will be evaluated and given a disposition by the operator as to relevant or non-relevant indication. For example: This area can be highlighted on the strip chart and have an associated comment in the ‘comments’ section of the AUT chart or have any other code compliant technique for dispositioning these pulse echo responses such as go/no go bars.

15.3. Weld Acceptance from the Inspection Record

15.3.1. A weld shall be considered acceptable when the weld inspection shows discontinuities that do not exceed the tolerable values as given by the Company.

15.3.2. The Contractor shall submit ultrasonic reports to the Company daily, as directed by the Company, using forms approved by the Company. Contractor shall ensure that chainage is shown on the documents at maximum of 10 joint spacing (~800 foot 250 meter) intervals. Contractor shall ensure that all electronic data files and hard-copy graphs are further identified with the following:

Spread Identification Project Name Work Order Number Date Inspector’s Name Inspection Unit Number Weld Number

15.3.3. All completed hard-copy graphs shall be catalogued and packaged in corrugated cardboard boxes supplied by the Contractor. Boxes of mainline hard-copy graphs shall be number sequentially in folders of 100 with corresponding Calibrations.

15.3.4. Clear and legible interpretation NDE sheets shall be included inside the boxes for those 100 graphs catalogued in the corresponding folder. Each corrugated box shall hold approximately 2500 welds, including associated NDE sheet judging acceptance.




15.3.5. Contractor shall supply labels for the recorder chart boxes. The following information is required on the labels:

Project Name Work Order Number Weld IDs of contained Inspection Reports Box Number Name of Ultrasonic Technician responsible for Weld Interpretations

15.4. Data Management

Backups of all digital data shall be made on a daily basis with a minimum of two backups of each file on separate mass storage media. The working computer system disk shall not be considered as a backup.

15.5. Archives

At a recurring frequency approved by the Company (bi-weekly at a maximum), all electronic data files shall be archived on CD-ROM and presented to the Company. For these files, the Contractor shall supply MS-DOS or MS WINDOWS® viewing software and instructions for its use.

16.Additional Requirements

16.1. Weld Repair List

16.1.1. Weld repair lists shall be provided to the Company in electronic and hard-copy format each working day by 6:00 A.M.

16.1.2. Repair lists should report the weld quality, including outstanding weld repairs and/or weld cutouts, of all welds completed by the prime Contractor’s mainline welding crew, by 4:30 P.M. each day or an agreed upon time.

16.1.3. The Contractor shall have all necessary equipment and personnel on site to maintain a production rate that ensures any weld completed before 5:30 P.M. on any working day shall be inspected, interpreted, and included in the Ultrasonic Report for that working day.

16.2. Destructive Testing Equipment

‘Cut out’ Pieces shall be tracked and verified by a Company Representative. Samples shall be sent to an approved Materials Testing Vendor for sample verification when deemed necessary.

16.3. Training

Contractor shall provide training (one-day minimum) for Company Inspectors on the techniques of ultrasonic inspection. This training shall be at a date and location determined by the Company and shall occur before production welding starting on the project.

17.Records

17.1. Record Retention

The following records shall be kept:

17.1.1. Scanning Calibration, including:

Material and manufacture

17.1.2. Standard Records, including:

Date of manufacture of the standard Actual dimensions and angles of reference reflectors Actual surface roughness and outer profile

17.1.3. Search Unit Records, including:Highlighting indicates revisions made as of the date on this standard. Page 13 of 18



Make, date of manufacturing, and serial number Nominal dimensions Nominal frequency Height and wear

17.1.4. Ultrasonic System Records, including:

System description Make and model number of units operating procedure technique detail operator log

17.2. Report Format

Equipment performance logbooks, daily reports, and repair lists shall be presented to the Company in both hard-copy and electronic format. The format shall be comma-delimited ASCII, Excel, Word etc and be capable of displaying and printing the Electronic Report, Daily Repair Summary, and Repair List.

Evaluation of the acceptability of every weld inspection shall be reported on the "NDE Daily Report". The NDE Daily Report form shall be the only form used for NDE (UT, VT, RT, MT, and PT) for weld accepted/reject status. The Contractor shall ensure that station number or GPS coordinates are recorded with all applicable weld information on NDE Daily Report for all Tie-ins, all repair welds, start of new mainline and minigang pipe sections and every 800 foot (250m) interval thereafter (where applicable).

All completed ultrasonographs shall be catalogued and packaged on a daily basis. The Repair List shall consist of the following fields:

Date Weld ID Imperfection type Length in mm Position in mm from zero Upstream or down stream Depth in mm to the bottom of the imperfection Station number or GPS.

The Repair List shall retain all non-status welds and/or weld repairs until repairs are cleared or status is determined.

17.2.1. Reporting Production Statistics

Upon daily work completion, field personnel responsible for GENERAL NDE Reports shall turn in completed forms to the Coordinator. The Coordinator will subsequently distribute repair lists, production rates, and outstanding (non-status and un-repaired) welds.

Database statistics from previous day’s performance will also be provided in a hard- copy form. At a minimum, the report shall include (but is not be limited to) the daily repair % and ‘to-date’ repair %. The Contractor shall e-mail repair information to a list of Company personnel each day (to update the production history), in a graphical form accepted by the Company.

These reports shall be delivered to the Senior Weld Inspector or a designated representative by 6:00 AM unless another specific time can be mutually agreed upon.

17.2.2. Other Reporting Requirements

The Contractor shall report arc burns and other pipe imperfections observed visually, or where the weld does not meet the cap width or reinforcement criteria of the welding procedure. Indications not specified by ultrasonic acceptance criteria shall be noted as




V.I.R. (Visual Inspection Required). The Contractor is not responsible for specifying the accept/reject disposition of visual indications. The Company Representative/ Inspector shall be responsible for the disposition and sign-off of any visually-noted imperfections determined by the Contractor.




Appendix A - Specification for Manual Ultrasonic Inspection of Pipeline Welds

1. Scope

This specification establishes the requirements for manual ultrasonic examination of pipeline GMAW weld verifications and manual repair girth welds. When directed by the Company and/or qualified, this inspection technique can be used to verify other radiographed welds, longseam welds, loss of couplant indications on tieins and assist AUT tie-in inspection when repair areas are outside of covered scope. Referenced paragraphs in the main Ultrasonic Specification are indicated.

2. Requirements

2.1. Personnel

2.1.1. Personnel performing manual ultrasonic inspection shall be certified to a minimum of SNT-TC-1A Level II, in ultrasonic testing of butt welds in steel. Personnel shall have an additional 16 hours of contractor in-house training on manual inspection of girth welds. Additionally, a further 16 hours of training is required on the manual examination of pipeline girth welds using procedure-approved probes in a manual zonal inspection approach. Personnel shall demonstrate proficiency in calibrating portable A-scan instruments on the sensitivity calibration blocks with the selection of probes to be used to inspect different zones. Personnel must demonstrate proficiency in setting and interpreting both the amplitude scale and the time gates to determine location of received indications within the weld. Personnel must demonstrate proficiency in:

Defining probe standoffs Defining the location(s) of magnetic tape(s) to be used to keep the probe a set

distance from the weld centerline Ability to recognize linear versus volumetric echodynamic patterns Differentiate between geometry and actual weld anomalies

This operator training shall be documented and accompanied by a contractor in-house certifying exam.

2.1.2. The Company shall approve operators as described in Subsection 6.2.3. Manual ultrasonic operators shall be required to take the manual qualification test only.

2.2. Procedures

A procedure, specific techniques, and instructions for each thickness and variation shall be prepared (see paragraphs 6.3.2, 6.3.3, 6.3.4, and 6.3.5 of this specification). The procedure shall meet the requirements of API 1104, Section 11.4 .

2.3. Equipment

2.3.1. Ultrasonic equipment shall conform to the requirements of ASME Section V, Article 5.

2.3.2. Instrument “A” scan presentation shall conform to the requirements of ASME Section V, Article 5.

2.3.3. Instrument linearity shall meet requirements of Subsection 6.6 - Ultrasonic Equipment, of this specification.

2.3.4. Ultrasonic probes shall conform to the requirements of Subsection 6.6 - Ultrasonic Equipment, of this specification.

2.3.5. Sensitivity calibration blocks (sensitivity) shall meet the requirements of Paragraph 6.5 – Calibration, of this specification. The calibration blocks shall also conform to the requirements of the proposed API Sensitivity Reference Standard.

2.3.6. Reference blocks for angle beam distance calibration shall conform to the requirements of ASTM E164 Appendix 1.




2.3.7. Coupling shall be a water-based product. Water or gel (for which an MSDS sheet must be provided) may be used - but shall be completely removed upon completion of the test.

2.4. Calibration

2.4.1. MUT – AUT defect verification - zonal calibration shall conform to the requirements of Section 7 - System Set-Up, of this specification, except that individual probes shall be set up according to the parameters used by the automatic ultrasonic unit. The “standoff distances” shall be noted if different from the technique detail. Transfer value will be checked and documented for each weld procedure.

2.4.2. MUT – Weld Repair assessment shall conform to API 1104, 19th Edition – Section 11.4.5 – API Sensitivity Reference Standard. Manual ultrasonic testing shall be based on a two or three point reference level Distance Amplitude Correction(DAC). Transfer value will be checked and documented for each weld procedure.

2.5. Scanning

2.5.1. The repaired area shall be scanned ± 50mm either side of the repaired area. Tested acceptable areas shall be marked to indicate acceptance or rejection status and noted as such on the AUT report. If defects are present then specific MUT reports shall be required to describe the unrepaired defect. This form shall be approved by the company.

2.5.2. GMAW AUT transducer setups used shall mimic sensitivities from AUT calibration block when verifying GMAW indications and ensuring all GMAW defects have been removed in designated repair areas.

2.5.3. MUT fixed scans (i.e., the standoff distance for the probe and zone shall be determined and the probe shall then be set at this distance) with AUT transducer arrays can be used to assist the operator in GMAW defect verifications and removal confirmation. A magnetic strip can be used to keep the probe at the set distance for the length of repair. The adjacent zones may be examined in the same way for GMAW confirmation or removal.

2.5.4. The probes used shall be the same probe specification as the original mechanized test (i.e., probe beam angle shall be ±1.5 degrees for angles less than 45 degrees, or ± 2.0 degrees for angles greater than 45 degrees, and probe frequency, focus, crystal size and configuration shall match.).

2.5.5. The manual repair weld manual UT setup sensitivities shall be set off of N10 ID/OD notches with DAC curves. All interpreted indications shall be recorded on the report sheet.

2.5.6. The scans for manual repair welds shall be in accordance with ASME V article V and acceptable to the Company. A minimum of three angles shall be used to confirm the weld volume of the repair area. Ie. 45, 60 and 70 Degree.

2.5.7. When manual ultrasonic inspection of a repair weld is required, naturally focus probes are to be used. Root inspection focused transducers may be permitted for bead inspection. The test shall be conducted with a minimum of three different angles to a procedure based on ASME V article 5 and acceptable to the Company.

2.6. Recording

2.6.1. The “AUT” zonal defect verification setup – established with AUT sensitivies from the AUT procedure will be used for defect verification removal. Threshold gates when exceeded shall be recorded. Ensure all GMAW defects have been removed in their entirety.

2.6.2. All indications shall be noted above 50% of DAC with 6dB added (scanning and evaluation sensitivity) inspected with the 45, 60, and 70 degree volumetric inspection.




2.6.3. The acceptance criteria for GMAW/SMAW/FCAW repair areas performed by MUT shall be defined by API 1104, 19th Edition - Section 9.6.

2.6.4. In addition, all welds evaluated to API 1104 19th Edition Section 9.6 - Individual indications with a vertical height (through-wall) dimension determined to be greater than one quarter of the wall thickness and multiple indications at the same circumferential location with a summed vertical height (through-wall) dimension exceeding one half the wall thickness shall be considered defective.

2.6.5. Discontinuities and defects shall be noted numerically and diagrammatically on the report. Reports shall be pre-approved before fieldwork.

2.7. Reporting

2.7.1. At a minimum, reports shall include:

Operator Name and Date of Test Technique number or unique ID Zone(s) examined Thickness Gate start and length Repair or verification or other detail Position(s) and length(s) Coupling used (and removed) Probe(s) used (type, size, frequency) and standoff and gain setting Unique number of calibration (sensitivity) block used Defect/Discontinuity description, depth, location, size length, zone, and amplitude UT instrument serial number

2.7.2. All welds tested shall be reported on a separate report sheet(s) approved by the Company. The reports shall be handed to the Senior Weld Inspector on a daily basis to meet the requirements of Section 15 - Weld Inspection Record and Reports. The designated Job Supervisor shall verify the areas scanned against the interpretations made by both automatic ultrasonic inspection and manual ultrasonic inspection. The Job Supervisor shall record and store said data for review and transmittal to the Company. Reports shall be kept current and up-to-date with weld repair production.


Documents

C1071 - Ultrasonic Exam of Pipeline Welds