Answer: Usually including:
- Dimensional inspection: Outer diameter, wall thickness, length.
- Surface inspection: Checking for cracks, folds, scars and other defects.
- Non-destructive testing: Eddy current testing or ultrasonic testing (detecting internal defects).
- Chemical composition analysis: Spectral analysis to confirm material composition.
- Mechanical performance testing: Tensile test, flattening test, flaring test.
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