Dangers of the splash-zone for offshore structures

Providing the energy sector industries with the most advanced high-pressure cleaning, ultrasonic testing, and remote visual inspection technology, AISUS offers a suite of internal and external remote inspection solutions, for the increasingly complex challenges faced by customers operating in the harshest of environments.

Multi-skilled teams ensure the integrity of structures, inspected in the splash-zone or onshore, and are continually supporting ongoing global operations, field development or life extension projects.

In-house experience and the ability to provide quality data repeatedly helps clients to meet the required guidelines and mitigate expensive replacement programmes through early intervention strategies.

Company Details

Website: www.aisus.co.uk

Email: info@aisus.co.uk

Tel: + 44 (0)1224 222070

Address: Unit 21 Denmore Rd Bridge of Don Aberdeen AB23 8JW

DANGERS OF THE SPLASH-ZONE For Offshore Structures

The Splash-zone area is defined as a section of the structure that is periodically in and out of water due to the action of waves or tides. This area is difficult to inspect by the topside team and ROV surveys that typically struggle to clean and inspect in the -15m to LAT region.

These however are areas of high degradation due to the changing conditions, wave impact and the first subsea guide location.

Over the past decade, AISUS has found multiple defects and seen multiple cases where severed caissons have acted as dropped objects, closely missing critical subsea infrastructure that could lead to major incidents.

Not only do the structures face issues in the Splash-zone, but over time internal equipment such as pumps can lead to further internal damage.

Ultimately, these challenges can lead to unplanned shutdowns if there are no redundancy or mitigations put in place.

This is where the specialist technology and expertise of AISUS come into the equation like no other, accessing difficult areas to provide valuable data and solutions, that in many cases can be overseen or left as the unknown.

Internal Inspection

Remotely deployed and controlled internal solutions are ideal for use where access restrictions mean manual techniques offer limited or no inspection coverage or results. The full suite of technology including corrosion mapping, cleaning, visual, sampling and retrieval tools, provides solutions for pipework and structures above and below the waterline. AISUS has developed unique inspection systems for inspection in Caissons, J-tubes, Risers and Conductors.

External Inspection

Bespoke magnetic crawler using high-tech robotics that can be deployed on the topside down to the first subsea guide or through the support from a ROV for below the guide and provide quality Ultrasonic Inspection results. Other inspection capabilities like Pulsed Eddy Current (PEC) or visual can be deployed where required.

Visual

Utilising state-of-the-art visual inspection systems, solutions are provided for a variety of applications, from remote visual inspection of pipelines, caissons, tanks, and small-bore vessels to large platform leg inspections. Using 4K subsea camera systems, capturing images in 360 degrees, the Engineers can generate 3D models for assisting clients with further analysis of defects.

Cleaning

Offering a range of specialist high pressure (HP) cleaning solutions, AISUS has an extensive understanding of cleaning caissons, J-tubes, Risers, Conductors and Drilling riser joints internally and externally. The HP cleaning technology provides a clean surface free from loose debris, marine growth, corrosion, and coatings as required. The service can either be utilised for general pipe cleaning or when required to allow close visual inspection or successful collection of ultrasonic data.

Inspection

Utilising the latest in NDE software, live C-Scan maps provide a visual representation of wall thickness to allow the rapid screening. The full ultrasonic waveform is captured, allowing further analysis to be carried out using additional processing techniques, including surface profiling and cluster analysis. The inspections also provide the ability to confirm if degradation is internal or external and verify the current structural integrity of the component and identify any requirement for maintenance, repair, or replacement.

Data Management

AISUS’ data management system streamlines the maintenance and inspection activities of clients’ splashzone related components. Using a decade’s worth of inspection data and applying machine learning computer algorithms, AISUS can offer predictive modelling of splash-zone corrosion rates. The system also includes inspection images and ultrasonic thickness measurements that have been gathered from many component types.

Drilling Riser

The marine drilling riser inspection technology allows for the accurate measurement of wall thickness, weld integrity, riser bolts, riser inserts and main flanges without the need to remove buoyancy or the stripping down of equipment. Deploying the class inspections can either be onboard or on-site utilising advanced inspection techniques to provide an unparalleled riser inspection service.