| Method |
Magnetize the tube under test and locate magnetic flux 'leakage' from the surface as a result of a defect. |
| Application | Weld (not DSA) testing on-line, and full body testing off-line. Full body testing only possible on annealed product. |
| Product | All magnetic products, almost no size limits.
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| Advantages | High speed testing. Good sensitivity to both ID and OD defects. Sensitive to continuous defects. Non-contact or minimal contact with product. InspecTech has refined the technique to test small diameter ERW welds on line. |
| Disadvantages | In lager, heavy wall products huge magnetizing forces are created resulting in very large machines for full body testing. Interfering signals for ERW welds can limit full body capability. |
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