Post on 06-Mar-2018
Steve Kenefick NDE Principal Project Manager
IAEA/EPRI International Technical Meeting on Aging Management of
Buried and Underground Piping and Tanks for Nuclear Power Plants
October 13-15, 2014
Charlotte, NC
Buried Pipe NDE Technology
2 © 2014 Electric Power Research Institute, Inc. All rights reserved.
Overview
• Buried pipe NDE technology methods
for wall loss
• Technology limitations
• NDE technologies
• NDE delivery technology
3 © 2014 Electric Power Research Institute, Inc. All rights reserved.
Buried Pipe NDE Methods
In-line In-line & Outside Pipe
Outside pipe
Remote field testing
Ultrasonics Guided wave
Magnetic flux leakage
Electromagnetic techniques
Radiography
Saturated Low Frequency Eddy
Current
Electromagnetic acoustic transducer
Remote visual
Laser profilometry
In-line Delivery Methods
- Robotic Crawlers - Flow through - Pull through
4 © 2014 Electric Power Research Institute, Inc. All rights reserved.
Buried Pipe NDE Technology Capabilities
(General)
Method Volumetric Measures
Thickness
Change in
Thickness
Ultrasonics X X X
Remote Field Testing (RFT) X X X
Guided Wave X X
Magnetic Flux Leakage (MFL) X X
Radiography X X
Saturated Low Frequency Eddy
Current
X X
Laser Profilometry / Structured
White Light
X
Visual X
5 © 2014 Electric Power Research Institute, Inc. All rights reserved.
Ultrasonics
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Ultrasonic Principals
Energy generated by transducer into the
material
Energy travels in the material until
reflected, refracted, or attenuated
Reflected energy converted to electrical
pulse that can be processed and
displayed
7 © 2014 Electric Power Research Institute, Inc. All rights reserved.
Manual Applications
• Hand held single or dual element probes
– Spot thickness readings
– Scanning and recording specified
thickness (generally minimum or
maximum)
• Encoded manual or automated
• Phased array
8 © 2014 Electric Power Research Institute, Inc. All rights reserved.
In-line Ultrasonic Technology
• Ultrasonic tool inserted into piping system
• Moved through piping by fluid flow
– Fluid circulated behind tool and removed
in front of it
– Bi-directional tool (one access point)
– Single direction tool (launcher and
retriever)
• Robotically driven
9 © 2014 Electric Power Research Institute, Inc. All rights reserved.
In-line Launch and Retrieval Stations
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Ultrasonic Electromagnetic Acoustic
Transducer (EMATS)
• EMATs – another way to generate ultrasonic energy
• Probes are in close proximity to examination surface
11 © 2014 Electric Power Research Institute, Inc. All rights reserved.
Ultrasonic Display
Corrosion damage
around pipe support and
resulting C-scan display
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Ultrasonic Phased Array C-scan
Display
Scanned a 500-mm by 635-mm area of a corroded pipe
• ~80K measurements (some drop out)
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Ultrasonic B-scan and D-scan Displays
Inner Surface
Outer Surface
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Electromagnetics
Remote Field Testing (RFT)
15 © 2014 Electric Power Research Institute, Inc. All rights reserved.
RFT Sensor and Energy Flow
Courtesy of Russell NDE Systems Inc
• Uses Two coils
– Exciter (transmitter or send)
– Detector (receiver or pick-up)
– Coils typically separated by 2 to
3 pipe diameters
• Magnetic field inside the tube is
near zero, while external field is
strong
• Calibration on like material is
important
16 © 2014 Electric Power Research Institute, Inc. All rights reserved.
RFT Analysis Software
• RFT measures
– “Time-of-flight” (phase shift)
between coils which indirectly
relates to the wall thickness
– Signal strength (amplitude)
between coils
17 © 2014 Electric Power Research Institute, Inc. All rights reserved.
RFT Deployment
• Sensors can operate ~1-inch from
the metallic pipe surface allowing
for examination through scale,
tubercles, sand, deposits, and
liners
• RFT tools can be operated in a
tethered, guide-wire, autonomous,
or free-swimming form
18 © 2014 Electric Power Research Institute, Inc. All rights reserved.
Electromagnetics – SLOFEC
19 © 2014 Electric Power Research Institute, Inc. All rights reserved.
SLOFEC
Combination of eddy current and
magnetic field
• Superimposed DC magnetism
increases eddy current depth of
penetration
• Uses eddy current sensors to
detect flux leakage
• Density of magnetic lines increase
where wall thinning is present
20 © 2014 Electric Power Research Institute, Inc. All rights reserved.
SLOFEC
• In-line pipe inspections technique
for ferromagnetic materials
– Detection and resolution of
pitting
– Differentiates between inside
and outside surface
discontinuities
– Tolerate coatings and liftoff from
pipe surface
– Measure change in wall
thickness
21 © 2014 Electric Power Research Institute, Inc. All rights reserved.
SLOFEC
Loss-of-material on the far surface alters the magnetic flux, which in turn alters the eddy currents
• Loss-of-material on the
near surface directly
interrupt the flow of eddy
currents.
• These two responses alter
the phase angle of the
eddy current
22 © 2014 Electric Power Research Institute, Inc. All rights reserved.
Magnetic Flux Leakage (MFL)
23 © 2014 Electric Power Research Institute, Inc. All rights reserved.
Magnetic Flux Leakage (MFL)
In-line pipe inspections of ferromagnetic materials
• Detection and resolution of pitting
• Measures changes in wall thickness
• Cannot differentiate between ID and OD flaws
• Fast scan speeds
Photo curtsey of Microline Technology Corp
24 © 2014 Electric Power Research Institute, Inc. All rights reserved.
Magnetic Flux Leakage (MFL)
• Magnetic lines of flux flow between the magnetic poles
– Areas of corrosion or cracking interrupt this flow
• Flux lines are monitored with various sensor types placed
between the magnet poles
• Data is recorded and subsequently analyzed to identify and
characterize damage
Courtesy of Inline Devices – A Mears Group Company
25 © 2014 Electric Power Research Institute, Inc. All rights reserved.
MFL Field Application
Courtesy of Inline Devices – A Mears Group Company
Extensively used to
examine transmission
pipelines
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Other
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Pulsed Eddy Current
• Probe generates multiple frequencies in the material
– Measurements are made in the time domain
– Features near the inspection coils will be seen first
and more distant features will be seen later in time
Wall LossSignal
WallLoss
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Radiography
RT Techniques
• Double wall
– Qualitative assessment
– Detects localized pitting
– Can exam piping of larger
diameter
• Tangential
– Provides quantitative
thickness measurement
– Limited to small diameter
piping (< ~8” diameter)
29 © 2014 Electric Power Research Institute, Inc. All rights reserved.
3D Optical Scanner Technology
• Technology developed in conjunction with
pipeline industry
• Offers rapid characterization of accessible
corrosion
• Technology now commercially available
30 © 2014 Electric Power Research Institute, Inc. All rights reserved.
EPRI Buried Pipe NDE Guidance Report
EPRI Report 1025220: Buried Pipe
Nondestructive Evaluation Reference
Guide—Revision 2*
– Basic theory
– Technology selection guidance and
limitations
– Overview of techniques, equipment, and
applications
– Summary of remote delivery technology
* Revision 3 scheduled to published end of the year
31 © 2014 Electric Power Research Institute, Inc. All rights reserved.
EPRI Buried and Underground Pipe NDE
Reports
Nondestructive Evaluation: Buried Pipe Nondestructive
Evaluation Reference Guide—Revision 2 (1025220)
Nondestructive Evaluation: Buried Pipe NDE Reference
Guide—Revision 2, Addendum 1 (3002000447)
Nondestructive Evaluation: Assessment and
Development of Buried Pipe NDE Technology
(3002000463)
Buried Pipe Direct Examinations Through Coatings
(1025228)
Nondestructive Evaluation: Buried Pipe In-Line NDE
Depth Sizing Procedure (1025231)
32 © 2014 Electric Power Research Institute, Inc. All rights reserved.
EPRI Buried and Underground Pipe NDE
Reports
Intermediate Diameter Buried Piping Instrumented Vehicle-
-Evaluation (1022926)
Remote Field Technology Assessment for Piping
Inspection Including Buried and Limited Access
Components (1021153)
Catawba Field Trial of EPRI’s Large Diameter Buried Pipe
Instrumented Vehicle (1016676)
Buried Pipe Guided Wave Examination Reference
Document (1019115)
Guided Wave Analysis Tools for Buried Pipe (3002000466)
Guidelines for Obtaining Credit for Buried Pipe Guided
Wave Examinations (3002000468)
33 © 2014 Electric Power Research Institute, Inc. All rights reserved.
EPRI Buried and Underground Pipe NDE
Reports
Nondestructive Evaluation: Guided Wave Analysis Tools
(1025212)
Nondestructive Evaluation: Guided Wave Status Report
(1022929)
Nondestructive Evaluation: Further Developments of
Guided Wave Examination Application 2009 Status
Report (1019116)
Nondestructive Evaluation: Further Developments of
Guided Wave Examination Application (1016675)
Nondestructive Evaluation: Buried Pipe Structural Health
Monitoring (1025213)
34 © 2014 Electric Power Research Institute, Inc. All rights reserved.
EPRI Tank Reports
Nondestructive Evaluation: NDE for Tanks and
Containment Liners (3002000462)
Inspection Methods for Tanks and Containment Liners
(1025215)
Inspection Methodologies for Buried Pipes and Tanks
(1021561)
35 © 2014 Electric Power Research Institute, Inc. All rights reserved.
Together…Shaping the Future of
Electricity