Laser Leak Detection System - LDS1

SLD, jointly with Subsea 7, have developed an innovative technology to pinpoint minor leakage from risers in real-time. This patented technology is based on an ROV-mounted laser detection system that offers a step change in detection capability over conventional detection methods.

The laser leak detection system has proven to be capable of detecting small leaks from a long distance in murky water.

An application of this technology, in BP’s West of Shetland fields, has demonstrated impressive results in locating an area of minor damage to a riser outer sheath. Repairs have been carried out, thus securing the continued integrity of the riser.

Features

• Engineered to the highest safety standard.
• Modular Design.
• Maximum suitability for subsea environment.
• Remote leak detection, upto 20m.
• Real-time monitoring, 25 data rate per second.
• High sensitivity, minor leakages (<1 ppb).
• Daylight and intense ROV light has no effect on the detection.
• Built with alarm function to warn the ROV Pilot when Leakage is present.
• Built with various test system, for a user confidence.
• Robustly designed to absorb wave impacts to >4g.
• Suitable for any Workclass ROV.
• No expertise is required to operate the system.
• Optional Multi-detection capability for oil, injected hot water leaks and others.

Benefits

• Its guarantees to detect difficult leaks.
• Provide a high-speed riser inspection.
• Detecting leaks in murky water and buried under the sand.
• Easily detecting Leaks as the Fluorescein emits a clearly visible green light when excited with the blue laser.
• Easily showing which area is being inspected as ROV operator can observe the intense blue laser line projected on the riser.
• Capable of surveying the entire riser regardless of any difficult locations.
• The system has proven to be reliable and easy to use in actual offshore surveying environments.

Video Clips:

Underwater Demo

Under High Water Current

Pan & Tilt

Pan & Tilt Simulation

Smoke Test

Leak Detected (clips 1)

Leak Detected (clips 2)

Leak Detected (clips 3)

Leak Detected (clips 4)

Technical Specifications

Leak size resolution	>1mm in a puffing or continuous flow from a typical distance of 3m.
Detection sensitivity of fluorescein mix.	In air: 250ppm at a distance of 50m. In clear water: 25ppb at a distance of 12m. In murky seawater: 250ppm at a distance of 1.5m.
Pod dimensions	Max diameter 248mm x (L) 700mm
weight	in air: 36kg. In water: 6.5kg.
Power consumption	Wavelength 488nm. Power/Mode: 200mW/continuous wave
Projected laser line thickness/ width	At 3m distance from the source-10mm thickness by 1m widths (other beam dimension are optional).
Rotation and Tilt	Tilt: 45o above and 60o below the horizontal. Rotation: 360o.
Shock absorption	Up to a max acceleration of 4g in all directions.
Operating Temp.	0o - 40oC.
Heat sink	The internal pod operates, typically, at 10oC above ambient.
Galvanic correction	The system is anodised to withstand the normal water salinity.
Vacuum	250mbar
Depth rating	100m (other depths are optional).
Health & Safety	The system is classified as class 1 laser (eye safe) but contains class 3B laser. It is built with four safety interlocks.
Fluorescein test units	Internal unit contains 1ppb fluorescein sample.
Optical windows	The system incorparates high quality sapphire glass windows with highn scratch resistance, for both excitation and optical collection.
Other options	Crude Oil Leak Detection. Hot-water Leak Detection. Underwater 3D imaging.