API steel pipe is a low-carbon steel pipe widely used in structural and fluid pipes due to its ease of processing. However, the common problem with API steel pipes is the presence of pits and pockmarks on the surface, or easy cracking during later bending, flattening, and other processing, which affects the quality of customers' products. These problems cannot be solved by many seamless steel pipe manufacturers at present, but steel pipes can solve them mainly due to the following reasons: non API steel pipes contain only carbon elements and a certain amount of silicon and manganese for deoxidation, and do not contain other alloy elements (except residual elements), so it is particularly easy to cause surface pits during perforation.

API steel pipe is a pipeline pipe that belongs to the American petroleum standard. Pipeline pipes transport oil, gas, and water extracted from the ground to oil and gas industry enterprises through pipeline pipes. Pipeline pipes include seamless pipes and welded steel pipes, with flat ends, threaded ends, and socket ends; The connection methods include end welding, clamp connection, socket connection, etc.

The quality inspection of API steel pipes is particularly important. Generally, ultrasonic testing of API steel pipes is divided into online and manual methods. The online API steel pipe ultrasonic flaw detection wave is installed in the production line to perform online testing on continuously produced steel pipes. Once a defect occurs, an alarm will be triggered because the online ultrasonic testing equipment is automatic. Therefore, manual ultrasonic testing is also required for each batch of API steel pipes after they are taken offline.

Due to its special production process, API steel pipes use high-frequency welding, so the welding defect that generally occurs is lack of fusion. Also, because its current and voltage are controlled by machines, the phenomenon of lack of fusion in a quantity of API steel pipes is usually a long line. Therefore, ultrasonic testing of API steel pipes is relatively easy to judge. But it is necessary to require the testing personnel to have a fast testing speed. If the speed is slow, it will affect the efficiency of production and easily increase the amount of steel pipe waste