PR652-203801-R01 Large Standoff Magnetometry (LSM) Technology Literature Review

With improving accuracy and sensitivity of magnetic sensors, an attractive branch of the magnetic memory method (MMM) technique has been developed. Large Standoff Magnetometry (LSM) is an emerging non-destructive, remote, passive, non-contact and magnetic test method based on Villari effect, which could be applied to detect anomalies related to elevated stresses. The robust technology searches for Stress Concentration Zones (SCZs) in steel pipelines and ferromagnetic structures. These hot spots are mainly associated with corrosion, crack and mechanical damages such as dent and bucket, or landslide, which could be as a result of geohazards or external loadings. The technique has become very attractive because of its operational simplicity and economic advantages especially in hard-to-pig pipelines.

The LSM Technology has potential to be deployed as a screening tool to identify areas that require further examination, to improve target inspections, and prioritize excavations. At its current state of development, the technique could be considered as a complementary technique in integrity assessment technology. The applications of LSM technology include ground movement (geohazard), stress corrosion cracking, winkle bends, weld mismatch, buried casing, and depth of coverage prediction. Because it is a remote inspection technique, there are no limitations due to the pipeline manufacturing and installation conditions, such as curvature, weld type, thickness and diameter.