Non-destructive Testing Methods For Seamless Steel Pipe

The non-destructive testing method of seamless steel pipes is a technology used to detect defects or problems inside and outside the pipe without damaging the pipe surface. In this article, we will explore three common non-destructive testing methods for seamless steel pipes.

Magnetic Flux Leakage Detection Method

The magnetic flux leakage detection method employs the magnetic flux leakage principle to assess seamless steel pipes. In this inspection process, the seamless steel pipe under examination is initially magnetized. The surface of the seamless steel pipe only manifests a magnetic leakage field after magnetization. Utilizing sensors, this method captures information about the leakage magnetic field. Consequently, it is well-suited for automated flaw detection, enabling the rapid inspection of a substantial quantity of seamless steel pipes within a short timeframe.

Ultrasonic Detection Method

The ultrasonic detection method involves scrutinizing seamless steel pipes using electromagnetic induction principles. During this detection process, a beam of ultrasonic waves is first excited within the seamless steel pipe. This ultrasonic beam propagates inside the pipe, and if reflected, it indicates the presence of a surface defect. Throughout the inspection, ultrasonic waves induce a series of changes within the seamless steel pipe. Processing this information with a flaw detector allows for the comprehensive display of quantitative data related to the seamless steel pipe's defects. This method is capable of detecting various steel pipe defects simultaneously, offering high sensitivity. It's important to note that its relatively slow detection speed makes it suitable primarily for detailed inspections of high-quality seamless steel pipes rather than fast production lines.

Eddy Current Flaw Detection Method

The eddy current flaw detection method exhibits certain limitations during use, notably a detection blind zone that emerges at the end of the seamless steel pipe. The length of this blind zone is approximately 200mm. The testing equipment is primarily available in two forms: point probes and through probes. The point probe moves in a spiral pattern during detection, exhibiting lower efficiency and longer inspection times. On the other hand, the through probe, characterized by simple inspection equipment, rapid inspection speed, and high sensitivity, is the more widely employed option. Therefore, the eddy current testing method stands out as the most commonly used approach.