To perform ultrasonic testing of golden joints of the main gas pipeline, a procedure for mechanized ultrasonic testing was developed. The procedure complied with the requirements of EN ISO 13588:2019 inspection level C and EN ISO 10863:2020 inspection level C. Testing for transverse defects was carried out using conventional piezoelectric transducers using the echo-mirror method and frontal SAFT processing. The use of the AUGUR-ART flaw detector, the SPIDER scanner and the ECHO-scan and AUGUR-Analysis software demonstrated stable detection of defect simulators in the reference block. All this made it possible to analyze the shortcomings of welding at training joints and successfully perform golden joints of the main gas pipeline.