Steel Surface Quality Inspection

① Artificial visual inspection: lighting conditions, standards, experience, logos, pipe rotation.
② NDT inspection.
a. ultrasonic testing UT
More sensitive to a variety of materials uniform surface cracks and internal defects in materials.

b. electromagnetic induction eddy current testing ET
Mainly point (hole shape) defect sensitive.

c. Magnetic MT and magnetic flux leakage inspection
Magnetic detection for detecting surface and near surface defects in ferromagnetic material.

d. electromagnetic ultrasonic testing
Does not require a coupling medium, it can be applied to high temperature and high speed, rough dry pipe surface inspection.

e. penetrant inspection
A fluorescent, colored, testing of steel surface defects.