Non-destructive testing method for seamless steel pipe

Posted by chase Liu on November 18th, 2022

Seamless steel pipes have a hollow cross-section and are widely used as pipes for transporting fluids, such as pipes for transporting oil, natural gas, gas, water, and certain solid materials. Compared with welded steel pipe, seamless steel pipe has stronger bending and torsion resistance, and is an economical section steel

Non-destructive testing is a detection method that uses the physical properties of materials that change with defects to detect the existence of defects and the shape, size, location and development trend of defects on the premise that materials, equipment, structures, etc. are not damaged.

The definition and types of seamless steel pipe defects, defects refer to the lack of continuity and uniformity of material properties, or collectively referred to as discontinuity. In a narrow sense, a wound refers to a geometric discontinuity, which is a kind of defect. Generally, a wound and a defect are mixed together.

Several Commonly Used Seamless Steel Tube Defect Detection Methods

1. Ultrasonic flaw detection
It is a non-destructive testing method for testing internal defects of materials by using the influence of the difference in acoustic properties of materials and their internal defects on the propagation of ultrasonic waves, represented by the symbol UT.

2. Eddy current testing
A flaw detection method that uses the principle of electromagnetic induction to detect surface and near-surface defects of steel pipes, represented by the symbol ET.

3. Magnetic flux leakage detection
Magnetize the surface of the steel pipe, pick up the leakage magnetic field of the defect, form the defect electrical signal, and achieve the non-destructive inspection method for finding the defect, which is represented by the symbol LT.

4. Magnetic particle inspection
A kind of magnetic flux leakage inspection, which is a non-destructive inspection method that uses the phenomenon that the leakage magnetic field absorbs magnetic powder due to the generation of defects on the surface of ferromagnetic materials in a strong magnetic field, and is represented by the symbol MT.

5. Radiographic flaw detection
The flaw detection method that uses rays to penetrate the object to find the internal defects of the object is represented by the symbol RT.

6. Coloring flaw detection
Penetrant flaw detection (pt) is an inspection method in which a penetrating agent containing colored dyes (such as red dyes) is inserted into tiny cracks on the surface of the workpiece, and after cleaning, an adsorbent is applied to make the colored oil in the defect seep to the surface. A method of finding and judging defects based on colored spots and streaks.