Automated Ultrasonic Testing Systems for Bars and Tubes, Examples with Mono-Element and Phased Array Probes

This paper presents several examples for ultrasonic testing systems. Solid cross sections (bars and billets) and tubes (seamless and welded) are typical test tasks. The use of mono-element probes and phased array probes is compared.Systems for bars and billets with linear transportation and with rotational testing concepts (rotating bar/billet and linear probe movement) are presented. Large-scale immersion tanks for aerospace billets (aluminum, titanium, nickel-based alloys) provide the highest possible test sensitivity. The test tanks with high-precision mechanics sometimes use specially focused probes for multi-zone inspection (in accordance with SAE AMS 2628, SAE AMS-STD -2154, SNECMA DMC or MTU MTV 1033). A very large testing system was designed for forged bars with a diameters up to 1 m, lengths up to 10 m and weights up to 35 tons.The second part of the paper discusses testing systems for welded tubes. The tube welds can be electric resistance welds (ERW) or submerged-arc welds (SAW, longitudinal and helical) . Large wall thicknesses and the wide welds (SAW -pipes) lead to large testing volumes, especially if off-bead defects shall be detected. In addition, SHELL and some other test specifications ask for many test angles and probe positions. These requirements lead to a very large number of mono-element probes or suggest the use of phased array probes. Phased array probes with properly adjusted time-corrected-gain (TCG) and angle-corrected-gain (ACG) produce a uniform test sensitivity within the testing volume. This requires a proper design of probes, probe holders and test mechanics, e.g. by means of the CIVA software.

کلیدواژه ها:

ultrasonic testing (UT) ، phased arrays ، steel plant ، CIVA ، forged steel bars ، aerospace bars (titanium or nickel alloys) ، welded tubes