Ultrasonic Thickness Measurement for Ships and Offshore Vessels in Abu Dhabi

Inspection services for ships at Abu Dhabi

Each service has its own page with the method, the class requirements and what the report contains.

Where we gauge in Abu Dhabi: yards, berths and offshore bases

Most offshore-vessel thickness measurement at Mussafah takes place at the repair yards and marine bases along the Mussafah channel, which is lined with fabrication shops, workboat yards and slipways. Many of these vessels are docked on slipways or shiplifts rather than in a graving dock, so access to the bottom shell is good but the time out of the water is short. We work alongside the repair contractor so that readings on bottom plating, sea chests, the stern frame area and thruster tunnels are taken before blasting and painting crews move in.

Deep-sea ships are gauged at berths in Khalifa Port and Zayed Port, or at the anchorages off Abu Dhabi, when the scope is limited to piping, decks or a sample of tanks. Full renewal-survey programmes on large tankers and gas carriers need a dock, and when a ship owned or managed from Abu Dhabi docks elsewhere in the Gulf, we follow it to that yard. For offshore units between charters, idle time alongside is often the most practical gauging window of all, because the crew is available and the deck is clear of cargo.

• Mussafah marine and offshore yards — renewal-survey gauging of supply vessels, crew boats, landing craft and liftboats on slipways, shiplifts and repair berths
• Khalifa Port — hull gauging at Khalifa Port berths on boxships, vehicle carriers and multipurpose vessels during longer stays, with ISPS access arranged through the agent
• Zayed Port — piping and deck gauging on ro-ro, general cargo and cruise ships alongside the city berths, fitted around cargo and passenger operations
• Ruwais and the western terminals — gauging on product tankers and gas carriers at anchorage or lay-by, within the terminal operator's safety and permit rules
• Stood-down offshore units — gauging of accommodation barges, liftboats and jack-up hulls during idle periods between charters, when tanks can be emptied and ventilated
• Abu Dhabi anchorages — pre-purchase and on-hire condition checks of tankers and dry bulk ships, boarded from a launch the agent arranges

Regulation, ownership and the offshore market in Abu Dhabi

Port state control at Abu Dhabi follows the Riyadh MoU, the regime shared by the GCC states. Offshore support vessels are classed and surveyed like any other ship, with annual, intermediate and renewal surveys under the class society's rules, but their charterers add inspection regimes of their own, and offshore vetting through OCIMF's OVID scheme puts hull and deck condition under scrutiny before a vessel is accepted. No emission control area covers the Gulf, so MARPOL Annex VI's global 0.50% sulphur limit applies; the OSV fleet typically burns marine gas oil, so its corrosion problems sit in the hull, tanks and seawater systems rather than in scrubber piping.

Abu Dhabi is home to a large state-linked shipping and offshore logistics sector serving the national oil company, alongside private owners and managers running tankers, bulk carriers and workboats. The physical environment favours corrosion. Shallow coastal waters around the offshore fields are warm and saline, sediment and marine growth build up in sea chests and seawater cooling lines, and the cargo decks of supply vessels take constant abrasion and impact from pipe and container handling. Drill-water, brine, mud and fuel tanks on these ships corrode at very different rates, which is why a sound gauging plan samples each tank type separately rather than averaging across them.

Wherever a ship is outside a sulphur emission control area, the global 0.50% sulphur cap applies, and many of the ships calling at Abu Dhabi meet it with an exhaust gas cleaning system rather than compliant fuel. Scrubber wash-water piping, the overboard discharge and the hull penetration around it corrode quickly in service, especially on open-loop systems, and are worth adding to the gauging scope.

How a thickness measurement job runs at Abu Dhabi

A gauging job at Abu Dhabi runs the same way whatever the ship type. The sequence below is what the superintendent, the attending surveyor and the yard can expect from us.

The team flies into Zayed International Airport (AUH), Abu Dhabi's main airport, with direct services from a number of Indian cities; Dubai's airports are a practical alternative for jobs near Khalifa Port. Access to the Mussafah yards is arranged with the yard and the owner, Khalifa Port and Zayed Port need ISPS passes applied for by the ship's agent, and anchorage or terminal work needs a launch booked the same way. UAE visas are arranged before departure, so we need the yard date or the ship's ETA early, and we keep it under review as offshore schedules move.

• Send the vessel name or IMO number, ship type, class society, the survey due (annual, intermediate, renewal survey number, CAP or owner's condition survey), the port and dates, and the scope you expect.
• We confirm the scope against the class rules for that survey, prepare the thickness measurement plan with frame and section references, and say whether the measurement will be credited to a class survey.
• Mobilisation is planned around visa lead times and the vessel's schedule; the ship's agent arranges port access, and the yard or ship arranges staging, lighting, ventilation and gas-free certificates.
• Gauging with calibrated ultrasonic thickness gauges: through sound coatings only where the gauge's through-coating mode has been verified on a coated reference, otherwise on cleaned bare steel, with every reading tied to its frame, strake and location on the sketch.
• Readings are compared with original thicknesses as work proceeds; substantial and excessive corrosion and any cracks are reported to the attending surveyor and the superintendent the same day.
• The final report is issued on the class thickness-measurement formats with sketches, a summary of locations exceeding the allowable margins, piping tables where piping was in scope, and the gauge calibration and technician certificates.

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