Ultrasonic Thickness Gauging for Vessels Working from Montrose Port

Inspection services for ships at Montrose

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

Quays and windows for gauging at Montrose

All gauging at Montrose is done alongside. On a crew transfer vessel the scope usually covers hull plating from inside, fuel and water tanks, the bow fender structure that takes the push-on loads at the turbine boat landings, deck fittings and the mountings for any crane or gangway, and engine-room piping. Readings on aluminium need a different sound velocity setting from steel, and we check the setting on a reference block of the same alloy before starting. Larger service vessels and supply ships are gauged in the conventional way: decks, tanks, piping and, where requested, crack detection on crane and deck equipment foundations.

For a docking, vessels based at Montrose go elsewhere. Crew transfer vessels are often lifted out at a boatyard with a hoist, while larger offshore and cargo ships use drydocks such as Rosyth's or yards across the North Sea. The value of Montrose for an owner is that the vessel is close at hand for most of its working life, so condition can be tracked in small steps between dockings and the pre-docking steel and repair list prepared well ahead of the yard period.

• Wind farm operations quays — crew transfer and service vessel hull, tank, bow fender and deck fitting gauging between transfers.
• Offshore supply berths — deck plating, cargo tank and piping gauging while a supply vessel is loading or waiting on weather.
• General cargo berths — hold and tank gauging on coasters discharging forest products and bulk cargoes.
• Construction base berths — deck and crane foundation checks on project vessels supporting the Inch Cape build.
• Weather-bound days in port — longer scopes when easterly swell keeps the fleet alongside.

Port state control, wind farm charters and small-craft rules

Merchant ships and larger offshore vessels calling at Montrose come under port state control by the Maritime and Coastguard Agency, which inspects within the Paris MoU on the basis of UK legislation. Many of the smallest vessels in the wind fleet sit under different rules: crew transfer vessels are commonly built and operated to the UK Workboat Code or to class rules for high-speed and light craft, and their surveys look at hull structure, fendering and fittings rather than the cargo-area gauging programmes of a bulk carrier. The charterer is often the stricter judge, because wind farm operators audit vessels before and during a charter.

Oil and gas work from the port is assessed through operators' vessel assurance and OCIMF's OVID inspections, while wind farm owners run audit regimes of their own with similar expectations of documented hull and deck condition. For older supply vessels moving between oil and gas and wind charters, a current thickness record avoids awkward questions at the audit stage. The UK applies its own ship recycling regulations rather than the EU regulation, which matters mostly to owners selling older tonnage, and coasters trading to EU ports carry an Inventory of Hazardous Materials as they would at any continental port.

Ships trading to Montrose 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 Montrose

A gauging job at Montrose 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.

Aberdeen International Airport is the closer international gateway, to the north, and Edinburgh Airport serves arrivals from the south; Montrose has its own station on the railway linking the two cities. The team travels from India on UK visitor visas, so a fleet visit planned a few weeks ahead is easier to arrange than a single urgent call. Port access is arranged through the port authority, the vessel's agent or the wind farm operator's marine coordinator, and operators usually require site inductions before anyone boards their vessels.

• 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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