Ultrasonic Thickness Measurement for Ships at the Port of Rauma and Its Shipyard

Inspection services for ships at Rauma

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

Where a ship can be gauged in Rauma

The dry dock at the shipyard is where the largest scopes are done. Once the ship is dry and the yard has cleaned and ventilated the first tanks, we begin with the areas most likely to need renewal, usually the ballast tanks, the double bottom under the engine room and the ice belt, so that the class surveyor and the yard can settle quantities while steel can still be ordered without delaying undocking. Staging, lifts and lighting come from the yard under the owner's docking contract, and the readings go to the superintendent each evening, laid out so the yard's planners can size the renewal straight from them.

In the commercial harbour, gauging fits around the cargo. Forest-product berths give access to empty holds and tween decks before loading starts and to deck structure throughout the stay; the container terminal suits short deck and scrubber-piping jobs on feeders within one working day; and tankers at the liquid berths can have deck, piping and certified-safe void spaces measured under the ship's own permit system. A ship that loads at Rauma and is heading for a yard elsewhere can have its pre-docking steel estimate prepared during the call, and that estimate sometimes persuades the owner to dock at Rauma itself.

• Rauma Marine Constructions dry dock — renewal-survey gauging of bottom and side shell, sea chests and tanks on ferries, icebreakers and government ships in for repair
• Shipyard quays — afloat repair periods, where piping, deck and tank readings confirm which sections the yard should renew
• Forest-product berths — holds, tween decks and hatch covers on sto-ro and lo-lo ships, measured before loading begins
• Container terminal — deck plating and scrubber wash-water and overboard lines on feeders, completed within one call
• Liquid bulk berths — deck plating, cargo and ballast piping and safe voids on chemical and product tankers
• Anchorage off the port — ships waiting for a berth or for ice assistance, boarded by launch arranged through the agent

Port state control, ice rules and the Bothnian Sea trade

Port state control in Rauma is carried out by Traficom, the Finnish Transport and Communications Agency, within the Paris MoU, and boardings follow each ship's risk profile, so older bulk carriers and general cargo ships with past structural deficiencies are more likely to be inspected. The Bothnian Sea lies within the Baltic NOx emission control area for ships built from 2021 onwards. Voyages between Rauma and other EU ports have counted under the EU ETS since 2024 and under FuelEU Maritime since 2025, and the EU Ship Recycling Regulation obliges ships of 500 gross tonnage and upwards calling at EU ports to carry an Inventory of Hazardous Materials, which owners often bring up to date in the same docking that covers the renewal survey.

Ice class is the commercial lever in this trade. The Finnish-Swedish Ice Class Rules grade ships from IA Super downwards, and in a severe winter the restrictions for Bothnian Sea ports can climb high enough to shut out lower-class tonnage altogether. Charterers moving paper and pulp on year-round contracts therefore want ships whose ice class is secure, and that depends on ice-belt plating and frames keeping enough of their abrasion allowance. Thickness data from the bow, the forward shoulders and the midship ice belt gives an owner the evidence to keep a ship on such a contract, or the warning that renewal must come before the next season begins.

Ships trading to Rauma 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 Rauma

Most of the work on a Rauma job happens before the team boards: scope, plan and access are settled first, so the time on board goes on measurement.

Helsinki-Vantaa is the usual international gateway, and the team continues by road to the west coast; Turku Airport can shorten the journey on some itineraries. Shipyard access is arranged by the yard under the owner's docking contract, while harbour berths need ISPS passes that the ship's agent requests in advance, along with a launch if the ship is at anchor. Technicians travelling from India hold a Schengen visa for Finland, so we lock in dates once the docking slot or call is confirmed and leave room for consular processing.

• 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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