Icota Canada October 2008 Page 1 of 6

SOME NEW METHODS OF NDE AND SOME OLD RESULTS

Roderic K. Stanley Coiled Tube Resource Management

Houston, Tx, USA

Abstract We report on recent results of tests in magnetic flux leakage (MFL) and ultrasound (UT both conventional and phased array-PAUT)) that we have recently conducted. Introduction There are many NDE methods that could be used to improve the quality and reliability of coiled tubulars. Methods reported here include the following: 1. An analysis of the magnetic method for the wall

thickness of small diameter tubulars, both from the inside and the outside.

2. The development of a clamshell MFL system for CT inspection from the OD in the size range 1.000-2.875-in.

3. The results of tests conducted on CT using the ExxonMobil1 inspection requirements as a guide.

4. Tests performed as UT prove-up on MFL signals found during final inspection of new tubes.

5. Test performed using phased array ultrasound on butt welds and electric welds.

The Methods and their Results 1. Magnetic Wall Measurement Magnetic wall measurement represents a good non-contact way of detecting wall thickness problems in CT, (such as erosion and wear). It does not, nor was ever intended to measure other imperfections (note that “defects” in used CT are not yet defined). While the method was expounded in SPE 684232 for CT wall measurement, no detailed explanation of the underlying theory had been given. Work at Rice U (Houston)3 and itRobotics (Stafford, TX) lead to systems that measure wall magnetically from both the ID and OD. Good correlation between theory and experiment was found, as shown in Fig 1. These data were taken from the ID on a 5-in. OD tube with rings of increasing wall loss machined on the OD. (0-50%). Two runs of one axial sensor are shown. The variation in gauss levels at various wall loss

increments indicates the sensitivity of this technique at about 2 Gauss per 1 mil of wall.)

Figure 1: Two runs measuring the axial field inside a pipe with OD rings removed. The method has obvious advantages over contact methods since it can cope with foreign nonmagnetic material on the tube wall, with vibration and noise present. It is not accurate to 0.001-in., but then neither is UT. 2. A Clamshell Tubing Inspection System

Fig 2: Openable “Clamshell” CT inspection unit Requests for an openable (clamshell) system using non-contact techniques resulted in the head shown in Fig. 2. Permanent magnets are used to induce MFL and double axis hall-effect sensors are used for wall and flaw readings. Data from ExxonMobil-type test

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standards are given in Fig 3. and Table 1. Longitudinal EDM notches in these standards, cut from each end of a string, were not expected to be detected, and we certainly do not expect to see common seam weld defects such as penetrators, unless the cold welds around them have a different (lower) magnetic permeability than the surrounding steel.

Figure 3: Scans of one sensor over some of the reference indicators shown in table 1. The system inspects sizes 1.00 to 2 7/8, at which size, internal robots can take over, thus reducing cycles for larger OD tubing.. The inspections currently include:

(a) Magnetic wall thickness (b) MFL for defects (c) Ovality,

Skelp-end and butt welds are obviously detected because they exhibit different magnetic permeabilities

that tube walls, and therefore exhibit MFL. The computer capability allows the data to be transmitted, e-mailed, viewed from different angles, and processed in many different ways.

Table 1: Test results Note the spreading of the MFL over several sensors in table 1. Tool Needs: There is now a need to develop methods for (a) early detection of H2S damage, and (b) to classify defects other than by MFL signal amplitude. This represents a huge challenge. 3. Conventional EMI Results on EM Test Standards Reference standards (Fig 12) were made for an EM “final inspection” of a 32,000 ft. 1.75-in OD CT90 (HS90) string destined for Hibernia. Figure 4 shows the inspection using an ancient EMI unit (IOS-PCI). All reference indicators on both ID and OD surfaces were detected when the reference tube was run with the indicators at the hands-of-the-clock positions (12, 3, 6,9 o’clock) which are standard for OCTG inspections using rotating electromagnetic poles), except for a 0.25-in. long LID notch. (This is a consistency check

Figure 4: Final inspection set up of the unit’s ability to perform). When the notch length was increased to 0.50-in., it was detected. These notch sizes are now becoming standard in the new (draft) API Std for Coiled Tubing for final NDT after hydrostatic testing, which is a customer option in this document..

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Since detection sensitivity to ID flaws changes with wall thickness, (see table 1 for the 0.116 and 0-.175-in wall thickness results) it is impossible to maintain a constant level of sensitivity. We do the best we can. This “final inspection” of the tubing is done to detect mainly seam weld problems that were not detected on in-line units, or opened up during hydro. Currently, only rotating pole MFL units have been developed for this, although eventually offline UT units will be built to find the smaller seam weld defects that can pop open early in the life of a string. Recall that most EMI units only detect transversely oriented flaws, and do not contain sensors that search for these smaller in-seam longitudinal flaws. Since rotating pole equipment is very large, there is a need to develop small openable clamp-on devices that can find tight longitudinal defects. 4. Conventional UT Prove Up at the Seam For prove up of seam weld indications using conventional UT, we use SinΘ = 1-(4t/3D) to compute the plastic wedge angle (See Figs. 5, 6). This formula is used to put sound through a point 2t/3 from the OD, and so only minor reflections are seen from the back corner of the flash column in well made tubing i.e. there should not be a sharp corner or loss of wall

Figure 5: Suggested geometry for seam weld flaw inspection by UT. thickness at this point). The UT unit is standardized on a 10% deep ID EDM longitudinal notch (not shown in table 1) to 80% screen height, and a standardization line drawn on the UT instrument’s screen. Here, only the bottom part of the sound beam shown in Fig. 5 is used to standardize the system, but flaws in the seam weld become good reflectors (because they are almost perpendicular to the sound beam) as the transducer is vibrated by the inspector so that the entire sound beam scans the actual weld. Figure 6 shows a 58 deg plastic shoe wedge curved for 2.000-in. tubing that was successfully use on a job.

Figure 6: Plastic 58 deg wedge for sound entry into 2.00-in CT for seam weld prove up We have had success with reflections from the corners of thin walled sections (Fig. 7) next to the ID flash that cause large rotating pole MFL indications. (In-line eddy current inspections do not respond to this condition because their signal is differentiated out). In one test of a 0.134-in. (specified) wall tube section, UT prove-up signals such as Fig. 7 were seen for a considerable axial length. Compression wave UT found

Figure 7: Signal from ?? in the seam weld. that the wall thickness in the region of this indication was 0.114-in. on one side of the flash column only, well below the customer minimum acceptable wall of 0.129-in. The purchaser then performed FE analysis of the effect of this low wall condition, accepting the string, but de-rating the section in fatigue. 5. Phased Array Prove Up Alarmed that double wall radiography, (especially when conducted with “pills” emitting Gamma radiation) is not considered sufficient for the detection of the more critical weld defects (LOF, 2D cracks), we

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investigated a phased array ultrasonic (PAUT) method. Here, the probe consists of 16 minute (1/32-in dia.) in-line elements connected via a plastic wedge to a sophisticated computerized shear wave unit. The wedge is contoured to the tube surface, and scanning through the weld is performed by hand from both sides of the weld. This method provides effectively 50 sound beams in the material from 45 to 70 deg, at 0.5 deg angle increments, with an onboard computer reconstructing the reflected signals, in a variety of ways.. Since physics dictates using higher sound frequencies finds smaller defects (minimum detected flaw size = one half the sound wavelength used =λ/2) 5-10 MHz sound was used in PAUT for butt and seam weld inspections, and found to work extremely well, as shown in the examples below. The size and power of the PAUT instrument (seen in the PPT presentation) suggest that a simple kit can readily be developed for testing welds in offshore HPHT (or other) coiled tubing, field welds in coiled line pipe etc., without having to use radiography. This is currently the trend in pipeline inspection. The PAUT systems available today also make flaw sizing easier than with conventional UT, and this could be critical in determining whether to re-use strings with small flaws, for we have seen from the work of the Coiled Tubing Mechanics Research Institute (U of Tulsa) that often, only very little cycle life is “consumed” by ignoring smaller flaws. (a) Butt Weld Inspection: Figure 8 shows PA signals from a 0.009-in (5%t) deep x 0.125-in. long transverse EDM notch in the ID of a 2.000-in. tube. Line BO is the ID on the first UT leg. Figure 8: Phased Array signal from EDM notch. The reflected sound amplitude is set at 80% FSH on the A-scan, shown on the left of the figure. This is done to represent conventional shear wave at one particular angle, and uses a convenient entry angle that avoids large reflections from the ID bead. Other angles could have been reconstructed to accentuate other problems.

The right side of the figure is a Sector scan (S-scan) showing all sound entry angles from 45-70 deg, as are conventionally used for standard butt weld inspection, reconstructed by the computer using a colour scheme. ID and OD tube surface lines (BO, T1, B2) are drawn by the instrument. The small reference defect at the ID stands out. [At the 10 MHz used here, with a sound speed of 3200 m/s in steel, λ = 0.32 mm, so λ/2= 0.16 mm = 0.006-in. and the flaw is easily detected].

Using this method, 2 butt welds in tubing were inspected in the field from both sides by scanning axially through the weld, and then slowly rotating the transducer around the tube. This form of UT was selected since we felt that no amount of radiography would have detected 2-dimensional Lack of Fusion (FoF) in these welds. A standard for this inspection was written, with a reject criterion set at 20% FSH. As fig. 9 shows, no imperfections were found in the samples inspected, although there are deeper blue regions that are seen on the first leg just below half way through the tube wall.

Figure 9: Phased Array Signal from Butt weld We attribute these slightly larger reflections to larger grains within the weld material that in the body wall of the tubing that scatter the sound more and more as their average diameter approaches the wavelength of the incident ultrasound.

Production by the API Resource Group for Coiled Tubulars of a universal minimum standard butt weld document (manufacture and inspection) for CT is obviously needed because the current RT does not appear to address the detection of 2-dimensional LoF.

(b) Seam Weld Prove Up: Several samples of electric seam welds were scanned with PAUT. The transducer wedges were also curved to the pipe surface (rather like Fig. 6) to permit circumferential scans. The results are spectacular, as shown in figs 10 and 11. One advantage of this PAUT system is that the reflected sound signals can be reconfigured so as to best present the stored data. Thus here we have presented scans (known as C-scans) at one sound entry angle for several inches along to tube in the vicinity of

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the seam weld. This angle is arranged so that there is no interference (i.e false indications) from the internal flash. The C-scan is what one “sees” looking down onto the ultrasonic reflections. Figure 10 shows a large imperfection or defect at 51° on the 2nd ultrasonic leg (A and S-scans), and a lot of activity on the S-scan at high angles, e.g. 70°. The Level II inspector (not this author) indicated lack of fusion in several areas along the seam weld for about 18 inches (C-scan). The horizontal scale at the very bottom of the C-scan indicates the approximate lengths of these regions of LoF.

Figure 10: Elongated seam weld imperfections and defects. Figure 11 shows two indications on the A- and S-scans at 54° in otherwise very clean material. There are also nearby UT reflectors at 65-70° (S-scan) indicating that the causes are very close to the tube OD.

Figure 11: As fig 10. The C-scan is particularly revealing, with plenty of dark blue, and many red regions over a 19-in. length of

seam weld. It can be seen that some of these are very small, regularly spaced UT reflections at either end of this area. The total length of these inconsistencies, as evidenced by reflection of ultrasound, is indicative of an electric weld process that is out of control over these distances. 6. Origin of Seam Weld Defects Hydrostatic testing of CT is conducted for one reason – to see if the seam weld will leak before the tubing leaves the mill. The tubing is not held (Barlow formula, for 10 seconds) as in conventional OCTG7, but rather under additional forces throughout the tube wall that are caused by the bending, and changes with the diameter of the storage reel. Here, considerable hoop stress from bending must be added to the hoop stress from the hydrostatic pressure. Further, it is not a field test. Some seal welds leak, others do not. This depends upon what the hydrostatic pressure does to them, so that 3 situations can occur: (a) Burst, sweat, leak, (b) A flaw grows under pressure (c) Nothing. An interesting point emerges from such ultrasonic studies of seam welds, and is well known in electric weld circles. This is that hydrostatic test bursts are often not isolated events in the seam, but the culmination of electromagnetic and mechanical events occurring in and very close to the seam as the material passes through the “V” of the welder, and are often elongated on either side of the actual through-hole. Investigation of the content and cause of these reflectors provides fertile ground for interested scientists. The origin of seam weld problems (cold welds, penetrators) had been given in earlier papers4,5,6. They can be traced to any of the following: (a) lack of strip width control between certain

parameters, (b) damage on strip edges, such as dings and burrs. (c) defects in strip edges due to centerline

segregations, etc., in the hot-rolled strip, (d) lack of control of the electromagnetics of the seam

forging process. These lead to a variety of conditions such as cold welds, oxides of the metal constituents of the steel (CrO2, MnO, FeO, SiO2), and sections that just will not properly forge. Cold welds and very low densities of oxides may pass ultrasound, but at some point these sheets of oxides in the seam become mirrors to the ultrasound, and they are detected. The longer and deeper they are, the more chance they have of detection by UT, as here, but we see that some very short ones are detected here that were not detected in in-line electromagnetic inspection systems. The C-scan shows

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reflections for areas as short at 1/8-in. long. Such areas may not run entirely through the wall, just a short distance into it. Larger ones, or ones that run entirely through the wall, may blow on the hydrostatic test 7. Concluding Statements As CT is being placed in more critical environments, better assessment of the state of the tubing along its life is needed. The methods outlined above represent where we could stand at the present. Phased array inspection for the seam weld appears to be critical for detection of smaller seam weld imperfections. Nomenclature λ Sound wave length (= V/f) Θ Shear wave wedge sound entry angle D Tube outside diameter FSH Full screen height LID Longitudinal Test Flaw on Inside Diameter LOD Longitudinal Test Flaw on Outside Diameter LoF Lack of Fusion OCTG Oil Country Tubular Goods PAUT Phased-Array Ultrasonic Testing

TID Transverse Test Flaw on Inside Diameter TOD Transverse Test Flaw on Outside Diameter t Tube specified wall thickness References 1. ExxonMobil Standards for Coiled Tubing. 2. “Methods and Results of Inspecting Coiled Tubing

and Line Pipe,” R. K. Stanley, SPE 68423, April 2001.

3. “Simulation and Analysis of 3 Dimensional Magnetic Flux Leakage,” S. Dutta, F. Ghorbel, R. K. Stanley, IEEE Magnetics Transactions, 2008.

4. “Welding Phenomena and Welding Mechanisms in High Frequency Electric Resistance Welding–1st report,” Haga, H., Aoki, K. and Sato, T.: Welding Journal 59(7), pp. 208s-212s, 1980.

5. “The Mechanisms of Formation of Weld Defects in High Frequency Electric Resistance Welding,” Haga, H., Aoki, K. and Sato, T.: Welding Journal 59(7), pp. 103s-109s, 1980.

6. Thermatool website articles. 7. API 5CT, Specification for Casing and Tubing.

Figure 12: Reference Indicators used on a CT90 (HS90) “final inspection” of a string for Hibernia. Many of these reference indicators represent sizes that will appear in API 5ST – the standard for coiled tubing.

SOME NEW METHODS OF SOME NEW METHODS OF NDE AND SOME OLD NDE AND SOME OLD

RESULTSRESULTS

Roderic K. StanleyCoiled Tube Resource Management

Houston, Tx, USA

Icota, Canada, October 2008

Methods EvaluatedMethods Evaluated• Analysis of Magnetic wall measurement method• A clamshell 4-function EMI CT unit• EMI sensitivity tests using E-M as a guideline • Conventional UT prove-up of in-line indications• Phased array UT tests on butt welds• Phased array UT tests on seam welds• Acoustic Emission tests on CT were conducted

but are not reported here

Magnetic Wall Measurement 1Magnetic Wall Measurement 1

• First, build the robot to measure the wall.

• Then make it go around corners

• Put some permanent magnets in to magnetize axially

Measure the axial field on a test pipe surface.

And get a grad student to explain it.

Furnace robot tool

Internal CT tool

Magnetic Wall Measurement 2Magnetic Wall Measurement 2• Developed and explained mathematically at Rice U, Houston.• Methods works from the ID and OD of a tube. (Data are from ID)

• Detects as low as 5% wall loss on either surface.• Being patented

Sensor 7 data (2 runs). Rings of metal were removed from the tube OD; the robot travels up the inside. Note the large signal change are regions of wall loss- 2G/mil.

10%15%

20%

We can suppress this kick

Clamshell CT Inspection SystemClamshell CT Inspection System

• Openable• Uses Permanent

Magnets & multi-directional hall elements

• Measures wall• Detects transverse

defects• Measures ovality• Numerous forms of

viewing and analysing data

Design Criterion – meet draft API 5C8 4-function inspection requirements

To be added: Zone 1 capability, H2S damage detection

System has no high voltages

MFL Data MFL Data -- BBrr • Wall thick-nesses 116/ 175 represent the ends of a long Hibernia string.

• These reference defects are in the EM standard.

• Note the large gauss levels, and spread of MFL round the tube.

• Note that sensitivity to the same defect changes with wall thickness.

•Sensitivity to a 0.010-in deep OD pit was also achieved.

•Recent data on ambient wall thickness is also reasonably accurate.

•These reference indicators are now in API draft documents

MFL MFL Data 2Data 2

• Data from 0.175-in. and 0.116-in. walls on 2.000-in CT

• Vertical scales are different.

• Noise can be reduced much more than this with special digital filters.

• Digitization occurs at 0.7 mm axial intervals

SmallSmall DiaDia. Internal Coiled . Internal Coiled Tubing RobotTubing Robot• We Down-

sized the original robot and you can now put them in series.

• Can inspect 2.875-in. tubing

• Possibly reach to 2.375-in. OD tubing.

BINDT-2007

Internal NDE Pig dataInternal NDE Pig data

2.5 2.55 2.6 2.65 2.7 2.75 2.8 2.85 2.9 2.95 3

x 104

-80

-60

-40

-20

0

20

40

60

80

dis tance [inch]

magnetic flux density [Gauss]

Magne tic Flux De ns ity vs . Dis tance for S e ns or #10

radialaxial

416 ft

2.67 2.675 2.68 2.685 2.69 2.695 2.7

x 104

-60

-40

-20

0

20

40

60

dis tance [inch]

magnetic flux density [Gauss]

Magne tic Flux De ns ity vs . Dis tance for S e ns or #10

radialaxial

25"

20 Gaus sma in pit

sma lle r pits

Storage corrosion, depth unknown

ModellingModelling

• We have been doing some mathematical modelling of MFL signals at Rice University.

• It tells us when to switch over from one technique to another (external to internal).

• We have also performed tests to look at ultrasound entry into OD-corroded pipe.

3D MFL Math Modeling & 3D MFL Math Modeling & SimulationSimulation

We are attempting to solve the inverse problem of reconstructing defects via their MFL signals- More than one component is needed for classification

Final EMI Final EMI –– Hibernia StringHibernia String• These jobs are

always in August!• 32 k-ft string 2.00-

in. (0.175-0.116)• Magnetize axially

& scan for trans-verse defects

• Magnetize cir-cumferentially & scan for long-itudinal defects

• Prove up with conventionalconventional UT at the present

This is still the only wayonly way to get a full inspection in both directions (longitudinal and transverse)!

Reference Indicators Reference Indicators -- HiberniaHibernia

And now for something And now for something completely different………..completely different………..

• …John Cleese

Ultrasonic Methods for WeldsUltrasonic Methods for Welds• Seam Weld 1. Conventional2. Phased Array

• Butt Weld 1. Conventional2. Phased Array

Conventional Shear Wave for Conventional Shear Wave for Seam Welds.Seam Welds.

• Transducer is in plastic shoe curved to the pipe surface.

• Seam weld imperfections reflect sound back to transducer

• This guy is inspecting a spiral weld using 2.25 to 5 MHz sound, and has found something.

• System costs abt $7k • Such systems are

indispensible for many tool applications, not just CT & CLP

• Simple trigonometry [Sin Θ = 1 – 4t/3D]reveals distance to flaw and wedge angle. We have calculated wedge angles for all coiled tubing tables so as to avoid reflections from internal flash.

• This is faster than film faster than film RTRT and sees planar planar stuffstuff in seam welds that RT would tend to miss.

Shear Wave Shear Wave ––Seam WeldSeam Weld

MFL (but not in-line Eddy Current) may reveal low wall at points shown at bases of flash column, which can be measured with shear and compression wave UT

UT of Butt WeldsUT of Butt Welds• Ideal situation for

sound is the path ABCBA.

• Entry angle of 53°catches LoF on 37°faces that would be missed by RT.

•• Only Only one wallone wall to to contend withcontend with

• Major problem for RT & UT is the confusion caused by metal, or the lack of it, E and D Recall that X Rays have to go through 2

walls, & this reduces sensitivity.

Ellipse beam

Strait through beam

Advanced UT of Butt WeldsAdvanced UT of Butt Welds•• RT Not acceptableRT Not acceptable for planar defects

(which have high stress concentrations at the ends of the defects under bending loads, and fail quickly)

• Planar defects (e.g. sidewall lack-of-fusion, cracks) are better detected by ultrasound, since they reflectreflect

• There is much evidence for this from current pipeline weld inspection.

• UT is easier, cheaper, and faster than RT, and doesn’t need a radiation safety programme.

• UT is now very sophisticated, using more than one beam in the transducer

16 element phased-array weld probe

This crack might be wide enough to be seen by RT, but most tight ones are not

Advanced UT of Butt Welds 2Advanced UT of Butt Welds 2--Phased ArrayPhased Array

• 16 transducer system instead of 1

• 5-10 MHz Phased ArrayPhased Array

• Small reference indicator needed. Data can be stored in memory.

•Rapid scans are now possible from both sides of weld. It takes just a couple of minutes on CT.

• OD Surface prep is important to elim-inate spurious reflections, i.e. crown smoothing or complete removal.

• Method can be performed as acceptance of weld after mill RT has passed a weld.

•Performed very easily in the field to monitor welds, esp. offshore.

Unit and calibration notch weighs Unit and calibration notch weighs about 8 lb. Easy to transport offshore.about 8 lb. Easy to transport offshore.

What is Phased Array?…What is Phased Array?…• Multi-element pulses of sound,

controlled (phased) by a computer.

• Sound comes together right where you want it to.

• Beam angles from 40-70 and ½ degree intervals. (60 beams!)

•Can vary defect sensitivity by changing the frequency.•Many presentation modes are possible, to suit the inspection

•• Invented in CanadaInvented in Canada

A-scan

C-scan

S-scan

PA Equipment For CT Butt PA Equipment For CT Butt WeldsWelds

• RD/Tech “Omniscan” at 5 MHz

• Computer does everything, including storing the standardization from one job to the next.

• Highly portable and no radiation!

• 16 element UT probe looking 40° deg to 70° from either side of weld.

• Detects both 2D and 3Dboth 2D and 3Dimperfections in and close to butt-weld, or anywhere else……

Courtesy RD-Tech Smooth weld surface makes inspection easy

Phased Array Display for Shear Wave Phased Array Display for Shear Wave Butt Weld Inspection Butt Weld Inspection –– Ref Ind.Ref Ind.

These data taken at Q-Pro and stored in memory before we left for the field. Then checked in the field.

••Reflection from Reflection from EDM notch from EDM notch from 5050--6060°°, max at , max at 5656°°. .

••80% FSH set at 80% FSH set at ““redred””. .

•• EDM Notch EDM Notch depth 0.009depth 0.009--in., in., length 0.125length 0.125--in.in.

••Note rulers and Note rulers and use of use of colourcolour

ID

OD

ID

A-scan

S-scan

Weld Signal Weld Signal –– Tube Butt WeldTube Butt Weld• Field

inspection of butt weld

• Some noise from weld metal on 1st

leg.• Darker

blue-Possibly enlarged grains in weld which scatter sound

A-scan at 40 deg

Weld metalWeld metal

Tube wallTube wall

Tube wallTube wall

IDID

ODOD

ID2

Data were collected by Q-Pro in the field

S-scan from 40-70deg shows regions that can be sized –they reflect just a little more

A-scan looks just like noise, but the S-scan is more revealing

Data from a Data from a Fatigue MachineFatigue Machine

These PAUT signals were taken on samples that had been fatigued to death.

Lower one shows one through-wall FC and a lot of smaller (2ndry) cracks close to the main crack.

Seam Weld Phased Array 1Seam Weld Phased Array 1• Large through-

wall indication at one location(on all scans)

• Smaller indic-ations at 70 deg. on 1st leg.

• Light blue is very little scattering.

• Darker blue –more scattering.

• These indic-ations cover 18 inches of pipe length.

Data taken by Q-Pro, Houston

Phased Array on Seam Weld 2Phased Array on Seam Weld 2• About 19

inches of indications in this seam weld.

• Indicates edges not coming together in the weld “V” for complete fusion.

Data taken by Q-Pro, Houston

Closing CommentsClosing Comments• A ‘clamshell’ 4-function MFL inspection device is available.• The theory of the magnetic methods in CT inspection devices

had been studied and understood.• Final EMI has proved useful in testing Hibernia strings• UT methods continue to be investigated• A simple UT prove up for the seam weld has been put to use.• Phased array has been used on butt welds as a 2nd inspection• Phased array has been used on seam welds after hydro.• Phased array will make flaw sizing relatively easy.

CTRM remains ready to assist with your CT and CLP needs

Questions?