How to measure threaded flange corrosion?
The ultrasonic method is to measure the thickness of corroded pipe wall by using the principle of pulse reflection of ultrasonic wave. The basic principle of magnetic flux leakage method is based on the high permeability of ferromagnetic materials. The permeability of threaded flange corrosion defect is far less than that of flange. The threaded flange is magnetized under the action of external magnetic field. When there is no threaded flange defect, most of the magnetic lines pass through the steel pipe, and then the magnetic lines are evenly distributed. When there are defects in the threaded flange, the magnetic lines occur. Bending, and some of the magnetic lines leak out of the surface of the steel pipe. The defect can be judged by detecting the leakage flux escaped from the surface of the magnetized threaded flange.
In addition, the probe emits ultrasonic pulse vertically to the inner wall of the threaded flange. The probe first receives the reflected pulse from the inner surface of the tube wall, and then the ultrasonic probe receives the reflected pulse from the outer surface of the tube wall. The distance between the reflected pulse and the inner surface reflects the thickness of the tube wall.
The ultrasonic testing method is also suitable for thickness measurement and metal properties measurement of other metal structures.
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