Improvements in 500-kHz Ultrasonic Phased-Array Probe Designs for Evaluation of Thick Section Cast Austenitic Stainless Steel Piping Welds

A set of circumferentially oriented thermal fatigue cracks (TFCs) were implanted into three cast austenitic stainless steel (CASS) pressurizer (PZR) surge-line specimens (pipe-to-elbow welds) that were fabricated using vintage CASS materials formed in the 1970s, and flaw responses from these cracks were used to evaluate detection and sizing performance of the phased-array (PA) ultrasonic testing (UT) methods applied. Four different custom-made PA probes were employed in this study, operating nominally at 800 kHz, 1.0 MHz, 1.5 MHz, and 2.0 MHz center frequencies. The CASS PZR surge-line specimens were polished and chemically etched to bring out the microstructures of both pipe and elbow segments. Additional studies were conducted and documented to address baseline CASS material noise and observe possible ultrasonic beam redirection phenomena.

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Technical Letter Report Assessment of Ultrasonic Phased Array Inspection Method for Welds in Cast Austenitic Stainless Steel Pressurizer Surge Line Piping JCN N6398, Task 1B

10.2172/992378 ◽

2009 ◽

Author(s):

Aaron A. Diaz ◽

Anthony D. Cinson ◽

Susan L. Crawford ◽

Royce Mathews ◽

Traci L. Moran ◽

...

Keyword(s):

Stainless Steel ◽

Austenitic Stainless Steel ◽

Phased Array ◽

Inspection Method ◽

Ultrasonic Phased Array ◽

Surge Line

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Ultrasonic Phased Array Evaluations of Implanted and In-Situ Grown Flaws in Cast Austenitic Stainless Steel Pressurizer Surge Line Piping

ASME 2011 Pressure Vessels and Piping Conference: Volume 5 ◽

10.1115/pvp2011-57909 ◽

2011 ◽

Author(s):

Susan L. Crawford ◽

Anthony D. Cinson ◽

Traci L. Moran ◽

Matthew S. Prowant ◽

Aaron A. Diaz ◽

...

Keyword(s):

Stainless Steel ◽

Austenitic Stainless Steel ◽

Phased Array ◽

Fatigue Cracks ◽

Base Material ◽

Pacific Northwest National Laboratory ◽

Asme Code ◽

Ultrasonic Phased Array ◽

Surge Line

A set of circumferentially oriented thermal fatigue cracks (TFCs) were implanted into three cast austenitic stainless steel (CASS) pressurizer (PZR) surge-line specimen welds (pipe-to-elbow configuration) that were salvaged from a U.S. commercial nuclear power plant that had not been operated. Thus, these welds were fabricated using vintage CASS materials that were formed in the 1970s. Additionally, in-situ grown TFCs were placed in the adjacent CASS base material of one of these specimens. Ultrasonic phased-array responses from both types of flaws (implanted and in-situ grown) were analyzed for detection and characterization based on sizing and signal-to-noise determination. Multiple probes were employed covering the 0.8 to 2.0 MHz frequency range. To further validate the Pacific Northwest National Laboratory (PNNL) findings, an independent in-service inspection (ISI) supplier evaluated the flaws with their American Society of Mechanical Engineers (ASME) Code, Section XI, Appendix VIII-qualified procedure. The results obtained by PNNL personnel compared favorably to the ISI supplier results. All examined flaws were detected and sized within the ASME Code-allowable limits.

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Design Considerations for the Use of Ultrasonic Phased Array Probes in Weld Inspection

Volume 2: Integrity and Corrosion; Offshore Issues; Pipeline Automation and Measurement; Rotating Equipment ◽

10.1115/ipc2000-199 ◽

2000 ◽

Author(s):

Paul A. Meyer

Keyword(s):

Ultrasonic Testing ◽

Phased Array ◽

Design Considerations ◽

Array Probe ◽

Ultrasonic Phased Array ◽

Weld Inspection ◽

Service Inspection

Ultrasonic testing of metal welds has been in use for many years. Scanning methods using both contact and immersion methods are often used at the time of manufacture and also during periodic in-service inspection programs. But because of a variety of component configurations and potential flaw geometries it is often necessary to perform several inspections, each with a different probe configuration to assure adequate defect delegability. It is possible that a properly designed phased array probe can perform several different inspections without changing hardware thereby reducing inspection times. This presentation reviews the design and operation of ultrasonic phased array transducers and the necessary features to achieve the desired performance. Situations in which these probes have already been implemented effectively are also discussed.

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