Stainless steel seamless pipe quality defect inspection

The use of stainless steel seamless pipes is still relatively important for many buildings now. We also need to do a good job of checking the quality defects of stainless steel seamless pipes. Let’s talk about how to check the quality defects of stainless steel seamless pipes. Woolen cloth?

1. Eddy current flaw detection

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.

2. Magnetic flux leakage detection

The magnetic flux leakage detection method is to detect the defects of stainless steel pipes by magnetic leakage detection. By magnetizing the inspected pipe, a magnetic leakage field is generated on the defect part of the pipe surface. There are generally two types of magnetic flux leakage testing: magnetic field testing and magnetic particle testing. The magnetic field measurement method obtains the leakage magnetic field information through the sensor, which can realize the automatic detection of faults, and is suitable for the automatic detection of a large number of steel pipes. Magnetic particle inspection is easy to detect the outer surface of the steel pipe, and it has high sensitivity to detect defects such as cracks, wrinkles, thick skin, hair lines, and pinholes on the surface of the steel pipe.

3. Ultrasonic flaw detection

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.