Zynq SoC FPGA-based water-immersible ultrasonic instrumentation for pipe inspection and gauging

Abstract A re-programmable Zynq system-on-chip (SoC) FPGA-based water-immersible 2-channel ultrasonic instrumentation has been designed and developed and it is mounted inside the IP67-grade enclosures, which is suitable for ultrasonic pipe inspection and gauging applications. The novel, compact Zynq SoC FPGA-based ultrasonic instrumentation system, powered by lithium-ion batteries for its operation over five hours, exhibits its adaptability for challenging environments, including its ability to travel through pipes carrying oil or water. One of the salient features of the 2-channel system is the capability to acquire echo signals using 12-bit/100 MSPS digitizer to provide highly accurate values of the inner diameter (ID) and wall thickness (WT) of the pipe under test. The system has been utilised to acquire and store 256 MB of A-Scan data in the DDR3 memory module of FPGA. Subsequent to five hours of acquisition, data was transferred to the computer to reconstruct B-Scan cross-sectional images for 300 mm nominal bore (NB) Stainless Steel (SS), and Carbon Steel (CS) pipes machined with volumetric and planar standard flaws. The B-Scan images could reveal both types of defects along with the location and size of these flaws. Such ultrasonic instrumentation has become an advanced tool to acquire a large volume of gauging data for pipes operating in harsh conditions, making it a vital asset for the inspection of pipes containing crude oil or processed water for petrochemical and nuclear industries. This paper provides brief details about the ultrasonic PIG instrument, with few inspection results obtained for SS and CS pipes.