Modern Pipeline Inspection Techniques You Need to Know

The Challenge of Pipeline Integrity

The world's pipeline network spans millions of miles, transporting oil, gas, water, and chemicals. These critical assets face constant threats from corrosion, third-party damage, and material degradation. The Pipeline Integrity Hub covers operator-side integrity-management programmes (ILI planning, assessment intervals, threat-by-threat mitigation) at depth.

Corrosion is the dominant integrity threat across cross-country pipelines and refinery piping alike. Mitigation strategy — selection of cathodic protection, coating systems, inhibitor programmes — is covered in the Corrosion Engineering Guide, and the cost-of-corrosion arithmetic that justifies inspection spend lives in our risk-based inspection guide.

In-Line Inspection (ILI) - Smart Pigging

In-line inspection tools (smart pigs) travel through the pipeline propelled by product flow, collecting data on pipe condition without interrupting operations.

Magnetic Flux Leakage (MFL)

The most common ILI technology. Strong magnets saturate the pipe wall with magnetic flux. Metal loss causes flux to "leak" and is detected by sensors.

• Detects: Internal/external metal loss, corrosion pits, gouges
• Accuracy: ±10% wall thickness, ±10mm sizing

Ultrasonic (UT) Pigs

Use ultrasonic sensors to directly measure wall thickness by timing the reflection from inner and outer surfaces.

• Detects: Metal loss, laminations, inclusions
• Accuracy: ±0.4mm wall thickness

Geometry Pigs

Measure internal diameter variations to detect dents, ovality, buckles, and wrinkles from mechanical damage or ground movement.

Emerging Technologies

For sourcing pipeline-experienced contractors, NDT Connect's services overview lists ILI, GWT and PAUT capabilities by region. Houston operators can jump straight to Houston UT or compare cost bands on the Houston UT cost guide.