Thickness Measurement for Ships in Hull's Humber Docks

Inspection services for ships at Hull

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

Gauging locations in Hull's docks

At William Wright Dock, Dunston (Ship Repairs) offers dry docking and afloat repair for smaller ships, including tugs, dredgers, offshore vessels, fishing vessels, coasters and passenger craft. A ship in the graving dock gives full access to bottom and side shell, sea chests and the stern area, while tanks are opened and ventilated to the docking programme. Larger ships trading to Hull that need a drydock book yards on the Tees or the Tyne or across the North Sea, and we gauge them alongside in Hull beforehand so the yard receives the steel list early.

In the eastern docks, work is in service and follows the ship's schedule. The ferry is worked during its daytime stay at the King George Dock terminal, with the vehicle decks clear between discharge and loading. Container and general cargo ships are gauged around cargo operations. Vessels at Alexandra Dock loading blades or project cargo can have deck foundations checked before or after loading. At the Saltend jetty on the river, chemical tankers are worked inside the terminal's permit system, which usually confines the scope to deck plating and piping unless a tank has been certified gas-free.

• William Wright Dock: Dunston's graving dock and outfitting pier for docking survey and afloat repair gauging on smaller ships.
• King George Dock ferry terminal: vehicle-deck, ramp and tank scopes on the Rotterdam ro-pax, divided across daytime stays.
• Container and short-sea cargo berths in the eastern docks: hold, deck and ballast tank gauging during cargo work.
• Alexandra Dock: blade-carrying and wind project vessels, with deck foundation crack detection and plating gauging.
• Saltend jetty on the Humber: deck and piping gauging on chemical tankers within the terminal's rules.

Regulation and trade on the Humber's north bank

The Maritime and Coastguard Agency inspects foreign ships in Hull under the Paris MoU, which the UK continues to apply through its own law. Ships of 5,000 gross tonnage or more sailing between Hull and an EU port have half of that voyage's emissions counted under the EU Emissions Trading System, and FuelEU Maritime applies to the same half. For the Rotterdam ferries and the larger feeders, that has made hull efficiency a commercial matter: owners plan coating renewals at refit with more care, and thickness readings decide where steel has to be renewed before new coating goes on, rather than after.

Hull is part of the Humber Freeport, and its economy is leaning on offshore wind manufacturing, logistics and energy. For ships that means more project cargo, more blade shipments and more vessels on wind-related charters passing through the docks. Ro-pax ferries bring their own inspection pattern, set by heavy vehicle traffic: wastage and cracking around lashing points and ramp landings, wear on vehicle-deck plating, and corrosion in voids and tanks under the vehicle decks that are rarely opened in service. On ferries that fitted exhaust gas cleaning systems, the wash-water lines and overboard connections deserve a regular wall-thickness check as well.

Ships trading to Hull are inside a sulphur emission control area, where fuel must not exceed 0.10% sulphur unless an exhaust gas cleaning system (scrubber) is fitted. Scrubber wash-water piping, the overboard discharge and the hull penetration around it are among the fastest-corroding parts of a modern ship, so they belong in the gauging scope at every docking and, on open-loop systems, between dockings.

How a thickness measurement job runs at Hull

The sequence for a thickness measurement job at Hull is short and written down, so the yard, the surveyor and the superintendent know who arranges what.

Humberside Airport, on the south bank, has a small route network, so most teams fly into Manchester, Leeds Bradford or a London airport and continue by rail to Hull Paragon, which has direct trains from London King's Cross. Our technicians come from India on UK visit visas, applied for well ahead of the job. ABP's dock estate is ISPS-controlled, and the ship's agent arranges passes and confirms lock times, which set when the team can board and how long the ship will stay.

• 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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