Pipeline Inspection Technologies Explained
Pipeline inspection is not a one-tool-finds-everything process. Different inline inspection (ILI) technologies are designed to evaluate different pipeline conditions, from changes in geometry and deformation to corrosion and metal loss.
Understanding what each technology measures—and what it does not—is an important part of planning an inspection program. The appropriate approach depends on the pipeline, operating conditions, inspection objectives, known integrity concerns, and the type of information needed.
Use this resource to explore common pipeline inspection technologies, understand what they detect, and find more detailed Enduro resources for planning your next inspection.
GEOMETRY & DEFORMATION
What changed in the shape of the pipe?
Caliper and geometry inspection technologies measure changes in pipeline geometry and can identify conditions such as dents, ovality, wrinkles, buckles and bore restrictions.
Best suited for:
Pipeline geometry and deformation
METAL LOSS & CORROSION
Where has the pipe wall lost material?
Magnetic Flux Leakage (MFL) technology evaluates changes in the steel pipe wall caused by corrosion, pitting, erosion and other forms of metal loss.
Best suited for:
Corrosion and metal-loss assessment
LOCATION & MAPPING
Where did the inspection findings occur?
Inertial, GPS, and mapping data help operators understand where inspection findings occur along the pipeline. GIS can further integrate ILI results with pipeline location, previous inspections, repairs, and other integrity data to provide greater context for evaluation and decision-making.
Best suited for:
Position, mapping & ILI data correlation
How Do Inline Inspection Tools Work?
Inline inspection tools travel through a pipeline while collecting information about the condition or geometry of the pipe. Depending on the inspection objective, the tool may use mechanical sensing arms, magnetic sensors, inertial measurement technology, or a combination of technologies to record conditions throughout the inspection run.
The collected data is analyzed after the run to identify, locate and characterize features that may require further evaluation.
The important distinction is that different inspection technologies measure different pipeline conditions. A geometry tool may identify a change in the shape of the pipe, while an MFL tool is designed to identify metal loss. For this reason, inspection technology should be selected according to the integrity threat or condition being evaluated.
Start With the Inspection Objective
Are you concerned about...
Dents, ovality, wrinkles, or restrictions?
→ Start with
Caliper & Geometry Inspection
Corrosion, pitting, or wall loss?
→ Explore
Magnetic Flux Leakage (MFL)
Tool passage or unknown pipeline geometry?
→ Consider
Caliper Inspection
Where inspection findings are located along the pipeline?
→ Explore
Mapping & ILI Data
Multiple integrity concerns?
→
Talk with Enduro about the appropriate inspection approach.
What Is Pipeline Deformation Inspection?
Pipeline deformation inspection identifies and characterizes changes in a pipeline's shape or geometry. Deformation can include dents, ovality, wrinkles, buckles, and other dimensional changes that alter the original pipe profile.
Caliper and geometry tools measure the pipeline's internal dimensions as they travel through the line, allowing operators to identify the location and characteristics of geometric anomalies. This information can also be important before running other inline inspection tools because significant restrictions or deformation may affect tool passage.
Geometry Tool vs. Caliper Tool — What's the Difference?
The terms geometry tool and caliper tool are sometimes used interchangeably because both evaluate changes in pipeline shape and internal dimensions. The terminology may vary depending on the tool design, sensing technology, and service provider.
Rather than relying on terminology alone, operators should consider the measurements and data required for the inspection objective. Enduro's caliper inspection capabilities are designed to provide detailed geometry information, including deformation measurement, bend analysis, and mapping.
What Is Magnetic Flux Leakage Inspection
Magnetic Flux Leakage (MFL) is an inline inspection technology used primarily to identify metal loss in steel pipelines. An MFL tool magnetizes the pipe wall and uses sensors to measure changes in the magnetic field as it travels through the pipeline.
How does MFL detect corrosion?
MFL does not detect corrosion simply by identifying rust. It detects the metal loss that corrosion leaves behind. Changes in pipe-wall thickness alter the magnetic field, producing leakage signals that can be recorded and analyzed.
Where corrosion, erosion or another condition has removed steel, some of the magnetic field leaks from the pipe wall. Analysis of these signals helps determine the location and characteristics of metal-loss anomalies.
One Pipeline. Different Questions..
Has the shape changed?
CALIPER / GEOMETRY
Has steel been lost?
MFL
Where is the feature?
MAPPING / IMU
Is the pipeline ready for the tool?
CLEANING + ILI PREPARATION
What Pipeline Inspection Tool Should I Use?
Selecting a pipeline inspection technology starts with defining what you need to learn about the pipeline. No single ILI technology is designed to identify every integrity threat.
Inspection planning may consider the suspected threat, pipeline diameter and geometry, product and operating conditions, previous inspection results, known restrictions, inspection history and the type of data required.
In some applications, multiple inspection technologies may provide complementary information about pipeline condition.
Questions to consider before selecting an inspection technology
- What condition or integrity threat are we trying to evaluate?
- Are there known dents, restrictions or geometry concerns?
- Is corrosion or metal loss the primary concern?
- Has the pipeline been inspected previously?
- Can the pipeline accommodate the proposed inspection tool?
- Is additional mapping or positional information required?
- Has the pipeline been properly prepared for ILI?
Inspection Starts Before the Tool Is Launched
Successful inline inspection begins with understanding whether the pipeline is ready for the inspection tool. Debris, black powder, mill scale, paraffin, liquids and other contaminants can affect tool passage and inspection performance.
Pipeline geometry should also be considered when restrictions or deformation could affect the safe passage of an ILI tool. Cleaning, geometry evaluation and inspection planning should therefore be considered together rather than as unrelated activities.
Preparing for Inline Inspection
Learn how cleaning, pipeline conditions and inspection objectives influence ILI readiness.
Pipeline Cleaning for ILI
Explore how cleaning programs help prepare pipelines for inspection.
Explore Enduro Pipeline Inspection Resources
Caliper & Geometry Inspection
Understand Enduro's pipeline geometry inspection capabilities.
What Does a Caliper Inspection Detect?
Learn about dents, ovality, wrinkles, restrictions and deformation.
MFL Inspection
Explore Enduro's metal-loss inspection technology.
What Does an MFL Inspection Detect?
Learn how MFL identifies corrosion, pitting and other forms of metal loss.
Preparing for Inline Inspection
Understand the factors that contribute to inspection readiness.
Pipeline Inline Inspection Services
Explore Enduro's broader ILI capabilities and support.
FREQUENTLY ASKED QUESTIONS
What are the main types of pipeline inspection technology?
Pipeline inspection technologies are selected based on the condition or integrity threat an operator needs to evaluate. Caliper and geometry tools are used to identify changes in pipeline shape, such as dents, ovality, wrinkles, and restrictions. Magnetic Flux Leakage (MFL) technology is primarily used to identify corrosion and metal loss in steel pipelines. Inertial, GPS, and mapping technologies can provide location and positional information that helps operators understand where inspection findings occur along the pipeline.
How do inline inspection tools work?
Inline inspection (ILI) tools travel through a pipeline while collecting data about the condition or geometry of the pipe. Depending on the inspection objective, a tool may use mechanical sensing arms, magnetic sensors, inertial measurement technology, or a combination of technologies. After the run, the collected data is analyzed to identify, locate, and characterize features that may require further evaluation.
What is pipeline deformation inspection?
Pipeline deformation inspection evaluates changes in the shape or geometry of a pipeline. Caliper or geometry tools can identify conditions such as dents, ovality, wrinkles, buckles, and bore restrictions. Understanding pipeline geometry can also help determine whether restrictions or deformation could affect the passage of other inline inspection tools.
Is a geometry tool the same as a caliper tool?
The terms geometry tool and caliper tool are often used to describe technologies that measure the internal geometry of a pipeline. Terminology can vary depending on the tool design and service provider. Rather than relying on terminology alone, operators should consider the measurements, inspection capabilities, and data required for their specific application.
What pipeline inspection technology is used to detect corrosion?
Magnetic Flux Leakage (MFL) is commonly used to detect and characterize metal loss associated with corrosion in steel pipelines. MFL tools magnetize the pipe wall and use sensors to identify changes in the magnetic field caused by areas where steel has been lost.
How do MFL tools detect pipeline corrosion?
MFL tools detect the metal loss caused by corrosion rather than simply detecting the presence of rust. When an MFL tool magnetizes the pipe wall, areas of reduced wall thickness cause changes in the magnetic field. Sensors record these magnetic leakage signals, which are analyzed to help identify and characterize metal-loss anomalies.
How do I choose the right pipeline inspection tool?
The appropriate inspection technology depends on what you need to learn about the pipeline. Operators should consider the suspected integrity threat, pipeline diameter and geometry, operating conditions, known restrictions, previous inspection results, inspection history, and required data. In some applications, multiple inspection technologies may be used to provide complementary information about pipeline condition.