Ultrasonic Pipeline and Well Casing In-line Inspection Services

What is Ultrasonic Testing

Dexon’s ultrasonic in-line inspection fleet utilises pulse-echo and angle beam ultrasonic inspection for the assessment of pipeline and production well integrity. Offering state of the art inspection capabilities across all materials and diameters of 3” upwards.

Ultrasonic Testing (UT), also known as ultrasonic inspection or ultrasonic non-destructive testing, is a non-destructive testing (NDT) method that employs high-frequency sound waves (ultrasonic waves) to assess the internal structure of materials and detect flaws or defects without causing any damage to the material being tested. The technique is widely used throughout the oil and gas and energy industry due to its ability to provide highly accurate direct measurements of a material’s internal structure, and the ability to accurately detect and size a wide range of defects. Ensuring the integrity of components, structures, and materials and avoiding failure of the asset.

Pulse Echo (Conventional Ultrasonic Testing):

Basic Principle: Pulse-Echo, also known as Conventional Ultrasonic Testing (UT), is the most fundamental ultrasonic testing technique. Relying on the transmission of a single pulse of ultrasound into a material, which then reflects back from the material’s interfaces, defects, or boundaries.

Transducer Configuration: Pulse-echo testing can use either single or multiple transducers depending on the application and inspection requirements, the fixed-angle transducers both send and receive ultrasound pulse echoes.

Applications: Pulse-echo is most commonly used for the detection and sizing of internal defects, measuring material thickness, and identifying material properties such as metal loss and geometric and ovality assessment. Pulse-echo ultrasound is used throughout Dexon’s metal loss inspection fleet from upstream oil and gas exploration and well inspection through to process piping in-line inspection.

Angle Beam (Shear Wave Testing):

Basic Principle: Angle beam, often referred to as shear wave testing, uses shear waves that travel at an angle through the material. Shear wave echos are generated within the material, which are used to assess internal defects such as cracking and crack-like defects.

Transducer Configuration: Angle Beam testing involves the use of transducers designed to generate and receive waves at specific angles, typically between 45 and 70 degrees, which allows for the inspection of materials with specific geometric configurations.

Applications: Angle beam testing is commonly used for inspecting welds such as ERW welds, detecting subsurface flaws, and examining materials with complex geometries such as cracks and crack-like defects.

Dexon’s Ultrasonic In-line Inspection Fleet

Metal Loss, Ovality and Feature Identification In-Line Inspection Capabilities

UT-R (Ultrasonic Rotary) Inspection

Dexon’s Ultrasonic Rotary (UT-R) in-line inspection fleet uses a single transducer and a rotating reflector to direct the ultrasonic inspection beam around the circumference of the pipe in a helictical pattern. Allowing for higher sampling resolution control by controlling inspection speeds. Recommended for pipelines of up to 10 km with a maximum tool speed of 5 m/min. Capturing ultra-high wall thickness and ovality inspection measurements. Click here for more information and detailed specs of Dexon’s UT-R fleet.

UT-MC (Ultrasonic Multi-Channel) Ring Inspection

Dexon’s Ultrasonic Multi-Channel Ring (UT-MC Ring) in-line inspection fleet offers high-resolution, high-speed, long-length inspection capabilities. Covering a wide range of materials, including both metallic and non-metallic pipelines. Rows of sensors around the circumference of the tool body record up to 80,000 measurements per second with sampling densities of up to 1,000,000 samples per square meter. The UT-MC offers detection and sizing of internal and external metal loss, ovality deformation, lamination, and corrosion. Tools are available from 3” up to 64” with larger custom-built tool options available.  Click here for more information and detailed specs of Dexon’s UT-MC Ring fleet.

UT-MC (Ultrasonic Multi-Channel) Octopus Inspection

The UT-MC Octopus fleet offers the same detection and sizing capabilities as the UT-MC Ring, with the addition of inspection in heavy crude oil and other speciality products with increased attenuation. Inspection capabilities are achieved via the use of arms that raise the transducers close to the pipe wall decreasing the time of flight of the signal and improving the signal-to-noise ratio. Click here for more information and detailed specs of Dexon’s UT-MC Octopus fleet.

UT-MC (Ultrasonic Multi-Channel) Well-Casing Inspection

Dexon’s specially built UT-MC well-casing inspection fleet offers rapid inspection of downhole well-casing strings and the accurate detection and sizing of metal loss and geometric defects. Accompanied by 24-72 hour comprehensive final reporting based on asset condition. Advanced ultrasonic sensors provide direct wall thickness data for the precise measurement of geometric and metal loss anomalies to ± 0.3 mm of actual wall thickness with axial and circumferential sampling distance of 1 mm. Click here for more information and detailed specs of Dexon’s UT-MC Well-Casing fleet.

Advanced Crack Detection and Sizing and Metal Loss In-Line Inspection Capabilities

UT-CS (Crack detection and Sizing) Inspection

Dexon’s UT-CS (Ultrasonic Crack Sizing) Hawk ILI System provides ultrasonic shear wave angle-beam tip diffraction crack inspection with variable sampling densities. Critical crack sizing is accomplished by combining extreme sampling resolution with proven data analysis algorithms and highly trained analysts. Providing accurate reliable crack detection and sizing down to 1mm of through wall height at 90% confidence. Click here for more information and detailed specs for Dexon’s UT-CS Hawk fleet.

The Advantages of Ultrasonic In-line Inspection

Direct Measurement:

Ultrasonic inspection techniques allow for the collection of up to over 1,000,000 individual wall thickness measurements per m² of material surface.  Returning precise metal loss, geometry and feature identification capabilities.  

Probability of Detection (POD):

UT testing allows for increased POD via customizable axial and circumferential sampling densities to meet individual inspection and assessment requirements. Dexon’s UT ILI fleet offers ultrasonic inspection resolution down to 1mm x 1mm, resulting in 1mm POD at 90% certainty.

International Engineering Assessment Standards and Reporting Criteria:

Increased wall thickness measurement accuracy obtained via higher sampling resolutions achieved with UT over other inspection methods allow for more precise engineering assessment calculations. API, ASME, and ASNT international assessment standards such as API 579, ASME B31G, FFS, RLA, and RSTRENG; return more accurate assessment results due to the increased accuracy of input data. Returning more accurate pressure calculations and reliable maintenance and repair recommendations. Inspection criteria and reporting conform with POF 100 2021 recommendations as a baseline. With more advanced inspection criteria and reporting standards available on request based on client assessment criteria.

Range of Inspection Materials:

Ultrasonic NDT techniques allow for the inspection of both ferrous and non-ferrous materials. Including carbon steel, high-density polyethylene (HDPE) and other plastics, and stainless steels. Seeing vast applications and benefits throughout the oil and gas industry from petrochemical plants and refineries to highly corrosive product transfer lines.

Detection Capabilities:

UT testing combines accurate detection and sizing of a range of metal loss and geometric anomalies in addition to pipeline feature detection and identification.

1. Metal loss POD is available to 1 mm @ 90% certainty with 0.3 mm depth sizing accuracy.

2. Internal radius measurements allow for accurate ovality and geometric anomaly assessment capabilities. Pipeline ovality can drastically affect a pipeline’s ability to efficiently transport product, decreasing profitability. UT inspection data can be used to accurately identify geometric anomalies.

3. Pipeline feature detection and identification and 3D mapping services provide a detailed assessment of a pipeline’s physical characteristics. Many older pipelines either have missing or inaccurate construction records. Ultrasonic inline inspection services allow for the complete restoration of as-built plans with location mapping for underground and subsea pipelines.

In-house Inspection Verification and Testing Facilities

Dexon’s head office features an extensive 7-acre pipeline inspection test yard.  The facility offers extensive in-line inspection testing and data verification, in addition to client pipeline configuration replication and testing.  Pull-through, pump-through and infinity loop test lines are available in various sizes ranging from 6” up to 44” in diameter.