Subsea lasers

 

Rrising to the challenge of riser integrity management

This summer, Savante deployed their fastest and most advanced subsea laser tooling aboard a WROV to conduct a 3D SLAM scan of a dynamic production riser and confirm the location of buoyancy elements used to maintain the riser catenary.

Costs, costs, costs

As at Sep. 2016, the oil and gas industry remains laser-focused on the difficult task of cutting costs at every conceivable level; all whilst protecting, maintaining and ensuring security of infrastructure, environment and personnel. Underwater inspection, maintenance and repair (IMR) operations, conducted by diver or remotely operated vehicle (ROV) are an essential component of an asset integrity management system yet are inherently commercially risky. At the lowest level of complexity an IMR survey consists of nothing more than a general visual inspection (GVI) record of an asset using a video camera. Whilst cheap; this can largely be insufficient and ineffective in addressing subsequent questions typically raised by asset-integrity managers.

Laser scanning; quantitative - not qualitative

The applications for lasers in the subsea environment are endless and growing to match the prevalence and diversity found in the onshore construction industry. Whether used for alignment, scaling, range-finding or creating full 3D models of subsea assets; lasers are now setting the underwater standard for speed, accuracy, ease of integration, ease of measurement and precision. Savante's latest laser technology shatters the established paradigm for riser inspection; achieving scanning rates exceeding 250Hz in a simple manipulator-mounted tool and combining visual recording with precision 3D data that can deliver decision-making clarity for asset integrity managers. Critically; this can be delivered dynamically on a moving-target, moving platform basis without the need to extend the duration of survey in field. Dr. Thomson, founder of Savante Subsea explains...

"the main benefit of subsea laser scanning is that it can be integrated seamlessly into any general visual inspection (GVI) campaign at low cost but delivers an enormous increase in capability and measurable content. Laser scanning retains the advantages of a GVI noted in DNV-RP-F206 of being " fast, low cost and able to cover large areas".
he continues... "Laser scanning dramatically overcomes the traditional criticisms of aGVI; namely " measurements not accurate, subjective and labor intensive". Laser scanning delivers essential measurement data that is vital in guiding the forward actions of asset integrity management. Our capacity to deliver this at the front-end of an inspection campaign can deliver significant cost-savings to the operator, particularly when it eliminates the need for a follow-up investigation."

The resulting buoyancy element position data was used as part of a hydro-dynamic modelling study to determine the maximum applicable loading forces anticipated during extreme environmental conditions and confirm safe operation. This project was driven by the requirements of a classification society.

Benefits and savings

Savante laser remote inspection delivered substantial benefits to the operator through;

  • direct contracting; achieving substantial cost benefits compared to even rental agencies.
  • rapid mobilisation (6 hour call-up); with negligible cable splicing requirements fulfilled on site.
  • 24-hour remote survey capability using scheduled onshore support; eliminating the requirement for additional offshore technicians and saving bed-space.
  • achieving a complete scan of the asset during a general visual inspection pass without incurring additional vessel time and without reducing the operational envelope of the ROV.
  • providing the first definitive asset infrastructure scan suitable for a high quality hydro-dynamic model.
  • eliminating the labor-intensive (and often subjective) determination of buoyancy element positions using endless review of video recordings.
  • eliminating the need for fragile, bespoke mechanical measurement tooling such as a vernier caliper and reducing the risk of physical contact between asset and ROV.

What Next?

Savante IS the answer to your subsea laser scanning requirements and we guarantee better results through our advanced technology and bespoke engineering solutions. In this fast-paced industry, we understand the value of precision, speed and costs and Savante can demonstrate the wide and varied cases of subsea laser scanning accomplishments and the value these have yielded to our international client base.

 
IDAC Media PC