The eddy current detection method detects a length of about 200mm from the pipe end, which is due to the limitation of the essential characteristics of the detection method. There are generally two types of eddy current testing equipment: point probes and through probes. During the detection process, the point probe moves forward in a spiral shape, making face detection time-consuming and inefficient. The penetrating probe has simple equipment, fast flaw detection, and high detection sensitivity when detecting cracks, concave surfaces, scars and external wrinkles on the surface of seamless pipes. It is one of the main methods to detect the quality of steel pipes.
Ultrasonic sensing method is a sensing technology based on the principle of electromagnetic effect. When the ultrasonic wave excited in the tube encounters defects on the surface of the tube during the propagation process, the beam is reflected and attenuated, thereby transmitting beam change information. After processing through the defect detector, the instrument provides a quantitative defect indication. This detection method can detect volume defects such as cracks, linear defects, and non-metallic inclusions in steel pipes. Although the detection sensitivity is high, it is almost impossible to use slow and fast online detection in steel pipe production. Therefore, this detection method is suitable for offline detection of high-quality steel pipes.