advancements in phased array scan planning
TRANSCRIPT
![Page 1: Advancements in Phased Array Scan Planning](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a62d151a28ab6f6d8b4569/html5/thumbnails/1.jpg)
Phased Array Scan PlanningConsiderations for Weld Inspection
University of Ultrasonics
Olympus Scientific Solutions Americas Webinar
February 4th, 2014
![Page 2: Advancements in Phased Array Scan Planning](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a62d151a28ab6f6d8b4569/html5/thumbnails/2.jpg)
• Scan Planning Introduction
• Basic Scan Plan Requirements
• Basic Methodology
• Hands-on Demonstration
Short Course Outline
![Page 3: Advancements in Phased Array Scan Planning](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a62d151a28ab6f6d8b4569/html5/thumbnails/3.jpg)
Scan Plan History• Scan planning is deeply rooted in day-to-day conventional
UT routines:
– Evaluating Transducer Characteristics
– Determining proper “pullback”/skip distance for Angle Beam
– Beam overlap for C-Scan coverage
– Focal Spot Size Calculations
![Page 4: Advancements in Phased Array Scan Planning](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a62d151a28ab6f6d8b4569/html5/thumbnails/4.jpg)
Scan Plans???• Before ANY Phased Array Inspection is
performed a SCAN PLAN should be in place.– Scan Plans – A documented inspection strategy (plan
of attack) to provide repeatability for inspections. These will aide in evaluating the material and provide insight to individuals reviewing data.
![Page 5: Advancements in Phased Array Scan Planning](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a62d151a28ab6f6d8b4569/html5/thumbnails/5.jpg)
Scan Plan Importance• Variability of Phased Array inspections can create issues in
consistency, repeatability, and personnel training
• The above scan plan includes several scan plan variables, can you find them???
![Page 6: Advancements in Phased Array Scan Planning](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a62d151a28ab6f6d8b4569/html5/thumbnails/6.jpg)
Phased Array Variability• Sectorial Scanning
• E-Scanning
• Encoded vs. Manual
• Aperture Determination
• Multi-Channel/Grouping
• Focusing effects
• Transducer Selection– Frequency & Beam
Spread Considerations
• Angle Selection
![Page 7: Advancements in Phased Array Scan Planning](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a62d151a28ab6f6d8b4569/html5/thumbnails/7.jpg)
Scan Planning
Code Perspective
![Page 8: Advancements in Phased Array Scan Planning](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a62d151a28ab6f6d8b4569/html5/thumbnails/8.jpg)
Scan Plan Variables
• Phased Array Scan plans should provide at minimum:– Part Details (Weld Design,
Curvatures, Connections)
– Probe and Wedge to be Used
– Focal Law Configuration to be Used (Including initial instrument settings)
– Index Offset Info
– Number of Scans
– Direction of Scans
![Page 9: Advancements in Phased Array Scan Planning](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a62d151a28ab6f6d8b4569/html5/thumbnails/9.jpg)
ASME Example Requirements
• Section V
Article 4
• Requirements
of Scan
Planning in
Appendix V
![Page 10: Advancements in Phased Array Scan Planning](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a62d151a28ab6f6d8b4569/html5/thumbnails/10.jpg)
AWS Example Requirements
D1.1
Info Related to Scan Planning under Part G
Testing Procedure under Annex S
![Page 11: Advancements in Phased Array Scan Planning](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a62d151a28ab6f6d8b4569/html5/thumbnails/11.jpg)
API Example Requirements
1104
Info Related to Scan Planning
Procedure specific
Specialized Calibration Requirements
![Page 12: Advancements in Phased Array Scan Planning](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a62d151a28ab6f6d8b4569/html5/thumbnails/12.jpg)
Phased Array
Scan Plan Equipment
![Page 13: Advancements in Phased Array Scan Planning](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a62d151a28ab6f6d8b4569/html5/thumbnails/13.jpg)
• Forming a scan plan involves 3 essential variables:
– Part Configuration
– Probe & Wedge Selection
– Focal Law Selection
• Information may be hand-drawn or plotted via software
Scan Plan Essentials
![Page 14: Advancements in Phased Array Scan Planning](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a62d151a28ab6f6d8b4569/html5/thumbnails/14.jpg)
• Pros:
– Accounts for errors in Equipment
– Plots actual beam index point
– Focal Law adjustments visualized
• Cons:
– Time Consuming
– Visual Measurements
– Requires Equipment
– Actual Inspection piece may vary
Hand-Drawn
![Page 15: Advancements in Phased Array Scan Planning](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a62d151a28ab6f6d8b4569/html5/thumbnails/15.jpg)
• Pros:– Fast and efficient
– Easier Part Drawing/Dimensioning
– Traceable & Transferable
– Flexibility on Custom Parts
• Cons:– Equipment Variations
– Part Variations
– Estimation of Focal Laws
– Manual Prove up required
Software
![Page 16: Advancements in Phased Array Scan Planning](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a62d151a28ab6f6d8b4569/html5/thumbnails/16.jpg)
• Choosing the proper equipment is as much scan
planning as choosing the proper angles or focal laws.
• Transducers should be proper for material properties
• Wedges should allow for good contact and transmission
• Instruments should be capable of handling both
Equipment Selection
![Page 17: Advancements in Phased Array Scan Planning](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a62d151a28ab6f6d8b4569/html5/thumbnails/17.jpg)
• Differences in array patterns will provide unique beam
characteristics
• 4 Primary Variables:
– Element Qty. - A
– Element Size - E
– Pitch - P
– Elevation - H
Element Configuration
p g
e
H
A
![Page 18: Advancements in Phased Array Scan Planning](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a62d151a28ab6f6d8b4569/html5/thumbnails/18.jpg)
• Focusing in Phased Array is
dependent upon the Aperture used
and Pitch of those elements
• Larger Pitch Transducers and Higher
Aperture sizes will provide better
focusing
• Sometime necessary when Height
Sizing is important
“VPA” Considerations - Focusing
16 element aperture
32 element aperture
![Page 19: Advancements in Phased Array Scan Planning](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a62d151a28ab6f6d8b4569/html5/thumbnails/19.jpg)
• Steering in Phased Array is dependent upon the amount of beam spread from individual elements
• Over steering a transducer can lead to grating lobes, resolution losses, and increased errors in refracted angle
• Smaller Element Sizes and Reduced Pitches aid in steering
“VPA” Considerations - Steering
![Page 20: Advancements in Phased Array Scan Planning](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a62d151a28ab6f6d8b4569/html5/thumbnails/20.jpg)
• Caution should be taken in using Phased Array in Axial
or Long Seam weld inspections
• Smaller equipment is easier to use as the compensation
through focal laws may not be necessary
• Larger wedges create non-linear focal law calculations
that sometimes require the addition of special software
Curvature Considerations
![Page 21: Advancements in Phased Array Scan Planning](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a62d151a28ab6f6d8b4569/html5/thumbnails/21.jpg)
Phased Array
Scan Plan Creation
![Page 22: Advancements in Phased Array Scan Planning](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a62d151a28ab6f6d8b4569/html5/thumbnails/22.jpg)
• From the perspective of the technician, a scan plan provides instruction for probe placement and focal law creation
• With no direct code instruction and high variance on Phased Array use, this leaves more room for interpretation and how to provide these instructions
• 2 Extremes of Scan Plan Creation– Minimalistic
– Flood Method
Scan Plan Thoughts
![Page 23: Advancements in Phased Array Scan Planning](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a62d151a28ab6f6d8b4569/html5/thumbnails/23.jpg)
• From a Code standpoint, coverage is the only requirement and the minimalist approach fulfills only that basic necessity
• Pros: High-Speed, minimal setup time, ease of analysis
• Cons: May require manual follow up, risk of undercalling, difficulties in flaw characterization
Minimalist Scan Plans
![Page 24: Advancements in Phased Array Scan Planning](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a62d151a28ab6f6d8b4569/html5/thumbnails/24.jpg)
• From a Detection standpoint, flaw orientation is always variable and is best detected by multiple beam positions
• Pros: High Resolution, Increased Probability of detection, Improved Sizing
• Cons: Slow Scan speeds, Longer Analysis/Setup times
Flood Scan Plans
![Page 25: Advancements in Phased Array Scan Planning](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a62d151a28ab6f6d8b4569/html5/thumbnails/25.jpg)
• First need a plan of attack….– How am I to approach the inspection? (Single side
access…duel side access..etc.)
– What types of flaw mechanisms are potentially present?
– What incident angles will best reveal the potential flaw mechanisms?
– FLAWS ARE ANGULAR DEPENDANT
• Most codes simply state full volumetric coverage including the Heat Affected Zone is required….. This is too vague.
• Breaking that required coverage into specific areas and specific angles will provide consistency and reliability.
Scan Plan Focal Law Methodology
![Page 26: Advancements in Phased Array Scan Planning](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a62d151a28ab6f6d8b4569/html5/thumbnails/26.jpg)
• More than just coverage!!!!
• Must interrogate specific parts of the joint with specific angles which will provide optimum responses to suspected flaw mechanisms.
• General coverage principles for Weld Inspection– Root Coverage
– Fusion Zone Coverage
– Heat affected zone coverage
– Volumetric
• This does NOT indicate that 4 scans on each side must be configured.…The number of scans is determined by your proof of coverage.
Scan Plan Methodology Welds
![Page 27: Advancements in Phased Array Scan Planning](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a62d151a28ab6f6d8b4569/html5/thumbnails/27.jpg)
• 1. Weld Root Interrogation – First objective is to index close to the weld toe with the intent of weld root interrogation– Primary Flaw Types: Lack of penetration, Root or ID Cracks,
Centerline Cracking in Double Vee Weld
– This is the most critical part of a weld joint and the first objective to cover in scan planning.
– First have to consider the joint type and the potential flaws.
– This also assures maximum 1st leg inspection coverage.
Scan Plan Methodology continued
![Page 28: Advancements in Phased Array Scan Planning](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a62d151a28ab6f6d8b4569/html5/thumbnails/28.jpg)
• 2. Fusion Zone Coverage – second objective is to ensure the fusion zone is covered WITH SPECIFIC ANGLES.
• Primary Flaw Types: Lack of side wall fusion, Sidewall Cracking
• With conventional ultrasonics, the optimum bevel incident angle (BIA) is considered between 5 and 7 degrees of normal incidence with some dependency on the frequency of the sound wave.
• Studies have found that with Phased Array, the optimum BIA with • Sectorial Scans = +/-10 degrees of normal incidence
• E-Scans = +/-5 degrees of normal incidence.
Scan Plan Methodology continued
![Page 29: Advancements in Phased Array Scan Planning](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a62d151a28ab6f6d8b4569/html5/thumbnails/29.jpg)
• Example:– With a 30 degree bevel – perfect bevel incidence would result
from a 60 degree refracted shear wave.
– Fusion Zone to be covered with refracted waves between 50 and 70 degrees (+/- 10 of 60 degrees.)
50
70
Scan Plan Methodology continued
![Page 30: Advancements in Phased Array Scan Planning](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a62d151a28ab6f6d8b4569/html5/thumbnails/30.jpg)
• 3. Heat Affected Zone (HAZ) Coverage – The total code specified area of interest must be covered. ASME specifies the weld zone plus 1” or “t” whichever is less for materials less than 3” thick.
– Primary Flaw Types: CRACKING
– Studies have identified that optimum responses from a notch corner result from shear waves between approximately 35 and 58 degrees.
– Plan for these angles to interrogate the HAZ zone.
– Occasionally, HAZ coverage may be specified as being achieved on the probe side for a given index position.
Scan Plan Methodology continued
![Page 31: Advancements in Phased Array Scan Planning](https://reader031.vdocuments.us/reader031/viewer/2022020123/55a62d151a28ab6f6d8b4569/html5/thumbnails/31.jpg)
• 4. Volumetric Coverage – If the previous three steps
are complete, this will be sufficiently covered without
addition considerations.
– This is for slag and porosity detection which are typically omni-
directional type reflectors (similar to a Side-drilled hole, omni-
directional reflectors tend to reflect sound regardless of the angle
of attack).
Scan Plan Methodology continued