Long Range Ultrasonic Testing (LRUT) brings significant power and rapid results to piping and pipeline inspection.
Long Range Ultrasonic Testing (LRUT) is an advanced non-destructive testing technique. LRUT uses low frequency ultrasonic modules and works by creating an ultrasonic wave form that travels both longitudinally and circumferentially, allowing long lengths of piping to be scanned. The technique is used to detect and analyse ultrasonic signals received as a result of metal loss such as corrosion and erosion.
LRUT, also known as Guided Wave Ultrasonic Testing (GWUT), gives pipeline operators a comprehensive look at their pipeline’s condition. Screening for localised thickness loss, ALS’s experts are able to detect for corrosion, erosion and mechanical damage by scanning from a single inspection location with signals transmitted in both directions along the pipe or piping.
LRUT applications include:
- Pipework, including examining for Corrosion Under Insulation (CUI) covering many metres from one scan location.
- Long steel cylindrical elements such as steel piles and structural cylindrical columns.
- Corrosion Under Pipe supports (CUPS).
- Buried piping, such as piping running under roads.
- Piping going through bund walls and other concrete structures.
LRUT is primarily applied on in-service pipelines.
Advantages of LRUT
LRUT is an excellent screening tool in long components, such as pipework, for evidence of localised thickness loss, including external and internal corrosion pits. Additional advantages include:
- The ability to measure significant pipe lengths from a single point.
- There is no need for scaffolding installation, coating removal or excavation.
- The ability to inspect pipes at temperatures up to 100°C.
- The inspection can be conducted whilst the asset is in service, removing possible production losses and downtime.
- Rapid inspection time and rapid results.
Limitations of LRUT
Limitations to LRUT inspection include:
- May have difficulty detecting very small isolated pits or pin holes.
- Unable to measure minimum wall thickness loss in mm, but provides loss measured as a percentage of the nominal thickness.
- Can be affected by some coatings, as well as some soils and moisture.
The ALS Approach
ALS continuously looks ahead and regularly invests in the latest technologies available to our industry. With continual advancement and superior customer value a priority, ALS is able to continually deliver the most advanced, efficient and effective inspection methods available in the asset care field.
Technologies such as LRUT, which supplement our existing inspection expertise, are embraced by ALS only after successful method validation, technician training and certification. This ensures a solid understanding of exactly where and how these technologies should be applied, and ensures all ALS inspectors are confident they will produce accurate results.