Crack identification Drone Guide

Oil and gas facilities contain extensive infrastructure that is continuously exposed to demanding operating and environmental conditions. Storage tanks, pipelines, processing equipment, flare structures, offshore platforms, pipe racks, chimneys, concrete structures and supporting steelwork can experience ageing, corrosion, thermal cycling, vibration, weather exposure and mechanical stresses.

Cracks can be one visible indication that an asset requires closer professional investigation.

Identifying these conditions can be challenging because many critical assets are elevated, difficult to access or located in hazardous environments. Traditional inspection may require scaffolding, rope access, elevated platforms or shutdowns simply to allow inspectors to reach an area.

Drones provide another method of collecting detailed visual information.

High-resolution cameras, optical zoom, thermal sensors, LiDAR and specialised imaging payloads can allow suitably equipped drones to inspect accessible external surfaces from appropriate stand-off distances.

Artificial intelligence can also assist inspectors by screening large image datasets for visual patterns that may warrant human review.

Drones do not determine the structural significance of a crack. Instead, they can help inspection teams find, document, locate and monitor visible indications so that qualified professionals can determine what further investigation is required.

Where Can Cracks Occur?

Oil and gas infrastructure contains many different materials and structures.

Visible cracking or crack-like indications may occur around:

• Storage tanks
• Concrete foundations
• Pipe supports
• Offshore structures
• Chimneys and stacks
• Flare-support structures
• Buildings
• Retaining structures
• Jetties
• Loading infrastructure
• Protective coatings
• Structural steel
• Process-support structures

Different materials require different inspection and diagnostic techniques.

Drone imagery should therefore form part of a broader asset-integrity programme.

High-Resolution Visual Inspection

High-resolution RGB photography is the primary drone technology for visible crack identification.

A suitable camera can collect detailed images of an asset from multiple angles.

Inspectors can subsequently zoom into photographs and examine areas requiring attention.

Unlike a ground observer looking at an elevated structure through binoculars, drone imagery creates a permanent digital record.

The same location can then be compared during future inspections.

Optical Zoom Cameras

Optical zoom is particularly valuable in oil and gas environments.

Rather than positioning the aircraft unnecessarily close to infrastructure, zoom cameras can collect detailed imagery from greater stand-off distances where conditions permit.

This is useful for tall structures, elevated pipe racks, tanks and other difficult-to-access areas.

Image quality, distance, lighting and viewing angle all influence whether small surface features can be reliably observed.

Storage Tank Crack Inspections

Large storage tanks require regular integrity-management programmes.

Drones can inspect accessible external tank walls, roofs, supporting structures and surrounding infrastructure.

High-resolution imagery can document visible surface conditions requiring further investigation.

Images can be associated with particular locations on the tank.

Future surveys can then return to the same areas to document visible changes.

However, drone photography cannot establish the depth of a crack or determine the remaining strength of the material.

Tank Roof Inspections

Tank roofs can be difficult to inspect because they may require personnel to work at height.

Drones provide an aerial perspective of suitable external roof surfaces.

Detailed photographs can document visible deterioration, corrosion, coating damage, deformation or potential cracking.

Areas of concern can then be prioritised for appropriate hands-on inspection.

Pipeline Crack Identification

External pipeline surfaces may contain visible deterioration or damage.

Where the pipe is above ground and visually accessible, drones can collect detailed imagery.

Pipeline supports, crossings and surrounding structures can also be inspected.

However, many important pipeline cracks are microscopic, internal, subsurface or otherwise impossible to detect using conventional aerial photography.

Specialist pipeline inspection technologies remain essential.

Pipe Rack Inspections

Refineries and processing plants can contain kilometres of elevated pipe racks.

These structures can be difficult to inspect comprehensively from ground level.

Drone cameras can document accessible supporting steelwork, structures and visible external pipe surfaces.

Images can be organised according to asset location.

This helps integrity teams determine where closer access may be justified.

Offshore Platform Inspections

Offshore platforms contain complex steel structures exposed to saltwater, wind, waves, vibration and industrial operating conditions.

Drones can support visual inspection of suitable external areas including elevated structures, decks, flare-support structures and other difficult-to-access components.

The ability to position a camera near elevated infrastructure can reduce some requirements for rope-access visual surveys.

Marine weather and confined operating areas create additional challenges requiring experienced operators.

Splash Zone Assessment

The splash zone of offshore structures experiences repeated wetting and drying and can be a demanding environment for materials.

Drones may document accessible above-water or near-surface external conditions where flight operations are appropriate.

High-resolution imagery can help integrity teams identify visible areas requiring specialist assessment.

Submerged structures normally require other technologies such as remotely operated vehicles.

Flare Structure Inspections

Flare-support structures can be extremely tall.

Drones can provide detailed imagery of accessible structural components without requiring personnel to climb the entire structure for every preliminary inspection.

Optical zoom can provide observations from appropriate distances.

Operating around active flare systems requires specialised risk assessment because of heat, turbulence, gases and other hazards.

Chimneys and Stacks

Industrial stacks can contain concrete, masonry, steel and other materials.

Cracking, surface deterioration and corrosion may develop over time.

Drones can capture detailed imagery across the external structure.

Photogrammetry can also create a three-dimensional model that allows observations to be associated with specific locations.

Concrete Crack Identification

Oil and gas facilities contain extensive concrete infrastructure.

Foundations, bunds, retaining walls, buildings and structural supports can develop visible cracking.

Drone photography can document these areas, particularly where they are elevated or extensive.

The imagery can help inspectors map crack locations.

Structural engineers must determine whether the observed cracking is superficial or potentially significant.

Corrosion and Cracking

Corrosion and cracking can sometimes occur in the same general areas.

Drone imagery can therefore be used to document multiple visible surface conditions during a single inspection.

High-resolution photographs can identify corrosion staining, coating deterioration and visible cracking.

This provides asset-integrity teams with a broader picture of external surface condition.

Coating Inspections

Protective coatings help shield oil and gas infrastructure from environmental exposure.

Coating deterioration can leave underlying materials more exposed.

Drone imagery can document peeling, blistering, discolouration and other visible coating conditions.

Areas requiring closer inspection can then be identified before maintenance teams are deployed.

Thermal Imaging

Thermal cameras provide information about surface-temperature patterns.

In certain specialised inspection scenarios, temperature differences can provide supplementary information about an asset.

However, thermal cameras should not generally be considered direct crack detectors.

Small cracks may produce no meaningful thermal signature.

Thermal data is therefore best used alongside high-resolution visual inspection and other appropriate techniques.

LiDAR

LiDAR creates detailed three-dimensional measurements of structures.

Although conventional drone LiDAR is not normally used to detect very fine cracks directly, it can provide valuable information about overall geometry.

Repeated surveys may support investigations of larger structural movement, deformation or changes.

Point clouds can also provide the geometric framework for managing visual inspection findings.

Photogrammetry

Photogrammetry can transform overlapping photographs into a three-dimensional representation of an asset.

This provides an effective method of organising inspection information.

Instead of storing thousands of photographs separately, inspectors can associate observations with their locations on a 3D model.

A user could select a section of a tank or structure and review imagery from previous inspections.

Artificial Intelligence for Crack Detection

Artificial intelligence and computer vision are increasingly being developed to assist visual inspections.

An AI system can analyse large numbers of drone photographs and highlight image regions containing patterns that resemble cracks or other deterioration.

This can significantly reduce the amount of imagery requiring initial manual screening.

However, AI can produce both false positives and missed detections.

Shadows, welds, stains, cables, coating marks and surface textures can sometimes resemble cracking.

Human verification remains essential.

Measuring Visible Cracks

Measuring cracks from imagery requires considerably more care than simply identifying them.

Scale, camera calibration, viewing angle, image resolution and distance from the structure all affect measurement accuracy.

Where reliable dimensions are required, the inspection system must use an appropriate measurement methodology.

A standard photograph without scale or calibration should not be assumed to provide an accurate crack width.

Repeat Crack Monitoring

One of the strongest advantages of drone inspection is repeatability.

Once an area of interest has been documented, future inspections can capture imagery from similar positions.

Inspection teams can compare observations between dates.

This creates a visual history of the asset.

Where accurate change measurements are required, consistent survey methodology and suitable measurement controls are essential.

Creating a Digital Defect Map

Drone findings can be geographically or structurally referenced.

Each identified observation can receive an asset reference, location, inspection date and associated imagery.

A digital defect map could contain information such as:

• Asset identification
• Location
• Photograph
• Inspection date
• Observation category
• Previous imagery
• Engineering assessment status
• Maintenance status

This transforms drone imagery into structured asset-integrity information.

Digital Twins

Digital twins can take this concept further.

A virtual representation of a refinery, offshore platform or storage terminal can contain individual assets and inspection histories.

Drone imagery, LiDAR and photogrammetry can update the external model.

An engineer could select a particular structure and review previous inspection observations.

This provides continuity between inspection campaigns.

GIS Integration

For geographically distributed infrastructure such as pipelines, drone observations can be incorporated into Geographic Information Systems.

Each observation can be associated with its physical location.

GIS can combine drone information with pipeline routes, maintenance records, environmental information and other asset data.

This supports broader integrity-management programmes.

Combining Drones with Non-Destructive Testing

Drone imagery is most effective when used to determine where specialist inspection should be concentrated.

If a possible crack is identified, engineers may use appropriate non-destructive testing techniques to investigate further.

Depending on the material and application, these can include ultrasonic testing, magnetic particle inspection, dye penetrant testing, eddy-current testing or other specialist methods.

These techniques provide information that conventional aerial imagery cannot.

The drone therefore acts as a screening and documentation platform, while NDT provides detailed material assessment.

Reducing Work at Height

A major benefit of drone inspection is reducing unnecessary initial access to elevated structures.

Instead of constructing scaffolding across an entire structure before knowing where potential problems exist, a drone can conduct a preliminary visual survey.

Inspectors can then determine which areas require physical access.

This can make inspection programmes more targeted.

Inspection After Severe Weather

Oil and gas facilities can be affected by hurricanes, storms, lightning, flooding and other environmental events.

Drones can rapidly document external infrastructure following suitable site clearance.

High-resolution imagery can help identify visible damage requiring further investigation.

This allows integrity teams to prioritise detailed inspections.

Construction and Commissioning Inspections

Crack identification is also relevant during construction.

Drones can document concrete structures, tanks, buildings and other infrastructure as projects develop.

Creating detailed visual records during construction provides a baseline.

Future operational inspections can then be compared with this original condition.

Automated Drone Inspections

Drone-in-a-box systems could make repeat inspections increasingly automated.

Permanent drone stations at large industrial facilities could conduct scheduled external surveys.

The aircraft could follow predefined routes and collect imagery from consistent locations.

AI could compare new imagery with previous surveys and highlight visible changes for professional review.

This could significantly increase inspection frequency.

Benefits of Drone Crack Identification

Using drones for crack-related inspection can provide several advantages:

• High-resolution visual documentation
• Access to elevated structures
• Optical zoom inspection
• Reduced requirement for some preliminary work at height
• Rapid inspection of large assets
• Offshore inspection support
• Repeatable imagery
• AI-assisted screening
• 3D asset modelling
• Digital defect mapping
• Historical condition comparison
• GIS integration
• Digital-twin integration
• Better targeting of specialist NDT
• Faster post-event assessment

The greatest value is often not simply detecting a crack, but creating a structured process for finding, documenting and monitoring visible changes.

Challenges and Limitations

Drone crack inspection has important limitations.

Very small cracks may be below the resolution of the camera.

Lighting, shadows, reflections, coatings and surface contamination can hide defects.

Many cracks occur internally or below the surface.

Image-based measurements can be inaccurate without suitable calibration.

Oil and gas facilities can also contain hazardous atmospheres, electrical equipment, heat sources and complex structures.

Not every drone is suitable for every industrial environment.

Professional asset-integrity assessment therefore remains essential.

The Future of Drone Crack Identification

Future inspection systems will increasingly combine drones, robotics, artificial intelligence, digital twins and automated NDT.

Autonomous drones could repeatedly inspect large external structures.

AI could compare imagery pixel-by-pixel with historical inspections and highlight areas showing potential changes.

Digital twins could maintain a complete visual history for individual assets.

Ground or climbing robots could then be deployed to areas identified by aerial surveys to perform specialist NDT measurements.

Rather than replacing inspectors, automation could allow engineers to concentrate their attention on the assets and observations most likely to require professional assessment.

Conclusion

Crack identification is an important application for drones within oil and gas asset-integrity programmes.

High-resolution cameras and optical zoom can provide detailed imagery of storage tanks, offshore structures, flare supports, pipe racks, concrete infrastructure, stacks and other difficult-to-access assets.

Photogrammetry and LiDAR can provide three-dimensional context, while artificial intelligence can assist with screening large image datasets and highlighting areas requiring human review.

The greatest value comes from combining these technologies with established non-destructive testing and engineering expertise.

A drone can help identify and document a visible indication, but it cannot determine by imagery alone how deep a crack extends, what caused it, or whether the asset remains structurally safe.

For oil and gas operators, refineries, offshore companies, pipeline operators, engineering firms and specialist inspection providers, drone-based crack identification can provide a faster and more data-driven method of targeting professional inspections and maintaining long-term digital records of critical infrastructure.