Austenitic weld inspection within the oil and gas industry is one of the most important assets for professionals in this field. But the inspection process can be daunting without the right equipment. Austenitic alloys and stainless steel resist corrosion more than other materials but are not impervious to corrosive degradation. Therefore, NDT inspectors must implement the same rigorous NDT standards on austenitic alloys and stainless steel as any other item.
The best way to test stainless steel and austenitic alloys is via PAUT using 2D matrix array probes. Stainless steel materials carry anisotropic coarse-grain content, with each grain causing reflections and high noise levels. The high noise levels result in greater feedback issues during conventional testing processes versus PAUT. Also, NDT specialists must deal with unintended variations within the structure of the pipeline, making testing difficult.
When inspecting an austenitic weld, for example, NDT operators can use the 2D matrix probes in the following ways:
Lowering frequencies between 1.5 MHz to 3.5 MHz for thicker components，Multiple channel configuration of focal laws to obtain wider coverage of the weld，Use steering in the passive plane to capture additional flaws.
The 2D capacity of the array allows users to angle wave beams throughout the testing stage, providing comprehensive beam coverage that canvases additional areas. A 2D matrix device can also find axial and circumferential flaws, especially awkwardly-positioned defects that could escape detection. A 2D probe yields added convenience and flexibility, but users can get the same resilience through NDT scanning equipment that can probe different welding types.