unlocking new applications w/ paut transducers · paut –tfm/fmc & htha high temperature...
TRANSCRIPT
8/26/19 1
Unlocking New Applications w/ PAUT Transducers
Steve Strachan – Sensor Networks, Inc.8/21/2019
AgendaPhased Array vs. Conventional UT Overview
Types of Phased Array UT Transducers
Phased Array UT Transducer Manufacturing• Development• Design• Prototype• Manufacture
Applications for Phased Array UT Transducers
Conclusion
Phased Array vs. Conventional UTQue es?: Using multiple channels of ultrasound (instead of a single channel) to be able to detect, measure, and image anomalies in a specimen under evaluation
Como funciona?: Using high end portable or stationary equipment capable of firing multiple channels of ultrasound
Por que?: • Increased POD (Probability of Detection)• Image and measurement capability• Speed at which one can inspect• Larger area inspection ability• Ability to more easily inspect complex
geometries & materials
Phased Array vs. Conventional UT
Conventional UT Equipment & Data Phased Array UT Equipment & Data
Phased Array vs. Conventional UT PROBES
Conventional UT Probes ($150-$3,000) Phased Array Probes ($3,000-$80,000)
How does Phased Array UT Work?
How does Phased Array UT Work?
Different Phased Array Types
Phased Array Nomenclature
Key Points• Big Aperture to
focus deep• Small elements
to steer far
How to BUILD a Phased Array UT Transducer?
https://www.youtube.com/watch?v=jkVTafD-e98
Transducer Story … in real life!
Incident: April 18, 2018 a critical failure of a Boeing 737 engine on Southwest Airlines flight number 1380 forced an emergency landing, in New York LaGuardia airport where multiple people were injured and a woman was killed.
https://abcnews.go.com/US/plane-makes-emergency-landing-philadelphia/story?id=54530003
Problem Statement
Root Cause: Stage 1 fan blade developed a fatigue crack which resulted in loss of containment (ejected blade)
Solution Requirements: Need inspection method to test existing fleet of engine blades in the field as accurately as possible as QUICKLY AS POSSIBLE
The Solution …
Fracture Mechanics Analysis: Engine manufacturer able to duplicate incident
Samples Manufactured: Had EDM notches put into new specimen to mimic fatigue crack, sent to SNI to have modeled, designed, and prototyped
The Solution …
UT Beam Modeling Computer Aided Design for Transducer
The Solution …
PAUT – TFM/FMC ... Great Technology …
Total Focusing Method or Total Electronic Focusing (TFM): electronic focusing which consists of adapting the receiving delay laws to focus at many points which form a grid, after a single pulse which generates a large and/or divergent ultrasonic beam
Full Matrix Capture (FMC): FMC specific data-acquisition process using ultrasonic array probes where each element in an array is successively used as the transmitter, while all elements are used as receivers for each transmitted pulse
PAUT – TFM/FMC ... But it’s all about the Probe!
Advantages of TFM/FMC:• Optimal focusing and spatial
resolution everywhere• Direct imaging of a large area
for one probe position• All reachable angles with the
array simultaneously• Defect characterization• Comprehensive imaging of
defect• 3D imaging
Element Steering
Depth/Focusing
Element Spacing
Frequency
PAUT – TFM/FMC & HTHA
High Temperature Hydrogen Attack (HTHA):• Petrochemical industry inspection
application• Characterization of stress or
corroded areas in hydrogen service above 200C in carbon steel assets
• Until now, probability of detection was <1%
• Today utilizing TFM/FMC & high end PAUT transducers, POD has increased to >10% DLA 10 MHz Probe: Pitch & Catch PA
64E w/ small pitch used in LW mode for improved TFM imaging
AL-TFM 5 MHz Probe: Pulse Echo PA 64E with small pitch used in SW mode for improved TFM imaging in HAZ under weld cap
Phased Array Nuclear Bolt Inspection
Overview:• Segmented-Annual Array• 360 degree electronic scanning• Displaced manual & motorized
scanning
Custom Phased Array Transducers
Custom Phased Arrays:• Nasa• Composite Backscatter• 253 discrete .125” transducers• 4.5” Radius• 10 MHz Alpha Transducers• Complex 5-Axis CNC Milling• Compound-radius Wedges• $80K selling price
Designing the New … Improving the Old …
Strain Relief: The most common failure of Phased Array transducers is undoubtedly the strain relief • Lasts @ 550K vs. 50K
cycles• Improve lifespan of
transducers by 10x
Designing the New … Improving the Old …
Low-Noise Wedges: Investing R&D into new noise-dampening material w/ similar acoustic impedance as the wedge itself• Increased Signal-to-Noise • Highly attenuative• Radiused for OD, ID, or other
complex radii exams
Conclusion
Understanding when to use conventional UT vs. Phased Array
Phased Array UT Transducers come in all different shapes, sizes, and configurations …
Select the RIGHT PROBE for the job
Custom solutions are being built all the time … test the boundaries!
Thank You!
Sources:• https://www.olympus-ims.com/en/• https://www.aos-ndt.com/product/fmc-tfm/• https://www.m2m-ndt.com/en/technology/pa-
techniques/total-focusing-method-tfm/• https://www.slideshare.net/ZetecNDT/principles-of-full-
matrix-capture-fmc-and-total-focusing-method-tfm-in-ultrasonic-inspections