1. Phased Array and 2 nd
leg inspection of DSS grade 2205 piping
Terry Chauvin, API QUPA #55359, AWS CWI #14061541
Abstract: A study was conducted to assess the ability of phased array ultrasonic techniques to detect
and accurately determine the size and location of 2nd
leg volumetric indications in duplex stainless
steel material. in purpose to prove a safer and more cost efficient method in lieu of computerized
radiography as well as compare inspection sensitivity. Achievement of alleviating the added cost of
weld reinforcement removal, 100% volumetric coverage, and code specific sensitivity were the
targeted results. For this study a 2” thk plate weldment was embedded with a 5% ID notch to capture
root resolution. Additionally, an 8.625" OD x 1.875" w.t. V-groove weldment was implanted with
planar defects and a l/8th
" SDH (side drilled hole) was added to determine if 2nd
leg sensitivity can be
achieved. Both samples were fabricated with isotropic duplex stainless steel grade 2205
Introduction: Long columnar grains from the austenite phase forms from the weld bead size and the
direction of maximum heat loss during solidification and cooling. The physical properties of the
structure of these grains can inhibit the ultrasonic response from scattered energy during propagation.
This in theory can obscure the detection of indications. This paper is to present the test results from
application of the Ist and 2nd
leg interrogation of an isotropic austenitic weldment.
Results: Lab trials for piping welds using multi-element 2.25 mhz. (2.25L16) single sectorial arrays,
including transmit-receive longitudinal (TRL) wave and transmit-receive shear (TRS) wave modes
configured to produce beam angles of 400
- 700
:
2” plate weldment w/ ID notch. (root resolution test)- In relation to shear wave, TRL results show
increased near field from ~.250" to ~.750". However optimal root resolution is achieved as compared
to TRS wave as seen illustrated in figure 1 & 2.
Figure 1 (SHEAR WAVE) Figure 2 (LOGITUDINAL WAVE)

2. 2” OD x 1.875” w.t. w/ implanted defects (2nd
leg sensitivity test)-
TRS results show a reduced near field but decreased root resolution.
2nd
leg SDH detection could only be achieved using TRS wave mode as seen in figure 3
UPPER VOLUME INDICATION
1/8" SIDE DRILL HOLE
ROOT INDICATION
1/8" SIDE DRILL HOLE (2nd LEG)
Conclusion: Results conclude that utilizing TRL and TRS in conjunction, PAUT is capable of accurately
detecting and sizing defects in the 2nd
leg of isotropic DSS grade 2205 without removing reinforcement.