Ultrasonic Thickness Measurement at the Ulsteinvik Shipyards

Inspection services for ships at Ulsteinvik

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

Yard facilities and where the gauging happens

At Ulstein Verft the dock hall is the centre of gravity: a vessel floated in is dry, sheltered and lit, and work on the shell, sea chests, rudder and double bottom can run in parallel with the yard's own trades. Afloat work on decks, accommodation and machinery spaces takes place at the outfitting quays. Green Yard Kleven's site has its own quays and steel production and handles repair and retrofit projects as well as recycling, where gauging and hazardous-materials surveys may both be needed before a decision on the hull is taken.

Whichever yard holds the contract, our team works for the shipowner or manager rather than for the yard, and fits its schedule to the yard's programme: blasting and painting must not cover areas that still need readings, and steel renewal cannot start until substantial corrosion has been marked and agreed. For vessels docking elsewhere in the cluster, at yards on the neighbouring islands or around Ålesund, the same approach applies, and we travel to whichever yard the owner has chosen.

• Ulstein Verft dock hall — shell, bottom, sea chest and tank gauging on vessels in dock for class renewal or upgrade.
• Ulstein Verft outfitting quays — deck, foundation and piping measurement during afloat repairs and upgrades.
• Green Yard Kleven — condition gauging and crack detection on vessels in for repair, retrofit or conversion.
• Green Yard Kleven recycling projects — IHM work and hull condition checks before an owner commits to recycling.
• Other yards on Hareidlandet, the nearby islands and around Ålesund — docking and renewal-survey gauging wherever the owner places the vessel.

A newbuilding cluster servicing an ageing offshore fleet

Ulsteinvik lies north of 62°N, so it falls outside the North Sea emission control area, and many vessels built and serviced in the cluster run on distillate, LNG or battery-hybrid systems in any case. Port state control on foreign ships in Norway is the task of the Norwegian Maritime Authority, under the Paris MoU, but for a yard town the more relevant regulator is the vessel's own class society, whose surveyor attends every docking and decides the extent of close-up survey and gauging. Retrofits for lower emissions, many of them part-funded by Norway's NOx Fund, have become a steady source of yard work on Norwegian vessels.

The offshore fleet that comes to Ulsteinvik for service is ageing. Many supply and anchor-handling vessels were delivered during the building boom of the years before 2015 and are now at or past their third renewal survey, the point at which the extent of gauging rises sharply. Owners deciding whether to keep, convert, sell or recycle such a vessel need thickness data to make that call, and yards like these are where the decision is carried out. For a ship going to recycling, the Inventory of Hazardous Materials has to be brought up to date before the work begins.

Wherever a ship is outside a sulphur emission control area, the global 0.50% sulphur cap applies, and many of the ships calling at Ulsteinvik 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 Ulsteinvik

A gauging job at Ulsteinvik 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.

Ålesund Airport, Vigra, is the main gateway, with flights from Oslo and other Norwegian cities, and Ørsta-Volda Airport at Hovden is closer still for domestic connections. From Ålesund the road to Ulsteinvik includes the ferry crossing from Sulesund to Hareid; from Hovden the Eiksund road tunnel links the mainland with Hareidlandet. Yard passes are issued by the yard at the owner's request. Norway is part of the Schengen area, so our technicians travel from India on Schengen visas, which fit easily around a docking date fixed weeks ahead.

• 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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