C-Gauge

Underwater laser based measurement system

  • Accuracy to 0.5mm

  • 2D and 3D display modes

  • 3000m depth rating

  • ROV mounted and diver held models

The field-proven C-Gauge underwater measurement system offers sub-millimetric underwater measurements. The highly compact and rugged package comprises C-Laser, laser detector and deployment frame designed to fit onto the smallest of ROV systems. Subsea measurement applications include pipeline crack, gap and ovality inspection, with precise point to point distance, diameter, radial and angular measurements. The system requires a single 24VDC input and video link to the analysis software package at the surface. A variant with a diver-friendly handle and function switch allows safer handling during diver held scanning operations.

Subsea anode depletion measurement

The laser measurement technology can inspect for signs of anode depletion, estimating the remaining life of subsea cathodic protection systems. As an integral tool for subsea structural inspection programmes, the system can quickly and accurately measure the dimensions and depletion of sacrificial anodes due to saltwater corrosion; a key concern for offshore asset management and integrity assurance operators.

FPSO mooring chain inspection

OceanTools worked closely with Inspectahire, the remote visual inspection specialists, to carry out inspections on subsea FPSO mooring chains for a client in Malaysia. The team carried out visual and laser inspections using C-Gauge to measure chain links and identify any defects, with great results delivered for the client on time and on budget.

The C-Gauge system fits to most ROV systems including inspection class ROVs, making it easy to deploy to carry out this type of inspection without the expense of a dive ship. In this case, a C-Gauge system with mounting bracket incorporating a fishtail handle was held securely by the jaw of the ROV's manipulator arm. The system can be deployed from the platform or FPSO deck and work to depths in excess of 100m.

FPSO bearing block inspection

A large E&P operator wanted to monitor wear on a bearing block on a North Sea FPSO turret as part of their major asset integrity program. OceanTools were requested to supply subsea technology capable of performing accurate remote dimensional measurements over two consecutive years, from which deterioration of the asset could be determined.

C-Gauge subsea laser measurement technology was mounted on a Video Ray ROV with a bespoke 3D printed laser rig. Multiple measurements were taken from various angles. The results from two identical procedures performed one year apart were captured and presented to the customer for analysis. The accurate results generated by the C-Gauge system allowed the customer to measure the rate of deterioration of a critical asset and design an efficient repair and maintenance program around its operational activities.