Detection of weld surface defects on offshore oil platform - Application of ACFM technology in Marine industry

1 Inspection background:

Due to environmental loads such as ice, wind and sea waves, offshore oil facilities are prone to corrosion, fracture, fatigue and other defects, so it is urgent to effectively detect the defects of metal structures in the Marine environment. However, due to its special working environment, complex detection objects and high detection, the detection of offshore oil equipment is difficult, the detection cost is high, and the detection efficiency is not high.

2 Inspection status:

At present, visual inspection is the main method for detecting defects in underwater parts of offshore oil platforms, but the underwater operating environment is inconvenient and the detection is difficult. Underwater magnetic powder and ultrasound have also been applied, but both of them are not easy to construct underwater, and the detection sensitivity is seriously reduced, so they are not used much.

3 Test method:

Ac electromagnetic field detection (ACFM) is a non-contact nondestructive detection method for surface or near-surface defects based on the principle of electromagnetic induction. The electromagnetic properties of the material in the underwater environment are not affected, and the design of the probe and the sealing performance of the inspection chamber and the pressure resistance can realize the defect detection up to 500 meters underwater.

4 Technical advantages:

1, compared with visual detection, digital detection results, easy to save data, traceability detection technology;

2, compared with underwater magnetic powder and ultrasonic detection, the principle of electromagnetic induction has little impact on underwater environment, and the detection sensitivity is consistent with the normal environment;

3, only need to clean the surface of the sea life, no need to polish to remove the paint layer, avoid the underwater magnetic powder required polishing work, improve the detection efficiency;

4, no coupling agent or consumables, cost saving, no pollution to the environment.

5 Typical applications:

Inspection of jacket welds on offshore oil platforms.