Thickness Measurement for Cargo Ships and Tankers in the Port of Norrköping

Inspection services for ships at Norrköping

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

Where a ship can be gauged in the Port of Norrköping

Norrköping has no drydock for seagoing ships, so the work here is done afloat. At the general cargo and forest product quays, holds can be measured as cargo is worked and tank tops become accessible, and ballast tanks can be entered once the crew has emptied, ventilated and tested them. The container terminal gives shorter windows, suited to scrubber piping, hatch covers and selected ballast tanks. At the oil harbour, any work aboard follows the terminal's rules and the ship's permit-to-work system, and is usually confined to spaces outside the cargo tanks.

When a ship needs a docking it goes to a repair yard elsewhere, in Sweden or across the Baltic, and Norrköping's part in that is preparation. Gauging during a loading or discharge call shows where substantial corrosion is likely, so the yard specification and the surveyor's close-up plan can be built around measured values rather than assumptions. Ships idle at the quays between cargoes give the longest windows, with time to open and ventilate tanks one after another. Winter work at the outer berths should allow for cold, wind and short daylight, which slow external measurement far more than work inside the hull.

• General cargo and forest product quays — hold, tank-top and hatch-coaming gauging while timber, paper or pulp is loaded.
• Container terminal — scrubber wash-water lines, hatch covers and selected ballast tanks measured within the feeder's berth window.
• Oil harbour — ballast tank, void and deck gauging on product tankers during discharge, with terminal approval.
• Dry bulk berths — hopper, topside and cargo hold readings as the holds empty, before the next cargo goes in.
• Quays used by ships between charters — full condition and pre-purchase gauging spread over several days.

Inspection regime, ice and emissions rules at Norrköping

Norrköping applies Paris MoU port state control through the Swedish Transport Agency, and the ships calling here are typical of the short-sea fleet that inspectors see most often: general cargo ships, small bulk carriers and feeders, many of them well into their second decade. Defects that lead to detentions on this kind of tonnage often involve hatch covers, air pipes, watertight doors and corroded deck fittings, all of which a targeted gauging scope can check before the inspector does. The EU ETS and FuelEU Maritime apply to ships of 5,000 GT and above, which brings the larger feeders and tankers into scope while leaving many of the smaller coasters outside it.

Winter shapes the year at the head of Bråviken. In cold seasons the inlet ices over, the Swedish Maritime Administration provides icebreaker assistance and may impose traffic restrictions that set a minimum ice class for ships heading in, and owners keep Finnish-Swedish ice class on their coasters partly for exactly this kind of port. Ice abrasion at the waterline, scraped coatings along the bow and the occasional indent are the marks a winter leaves, and spring is the season when owners of ice-classed short-sea ships most often ask for ice-belt readings and crack checks, so that repairs can be planned for the summer docking.

Ships trading to Norrköping 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 Norrköping

A gauging job at Norrköping 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.

Stockholm Arlanda is the usual international arrival, and trains run from Stockholm to Norrköping along the main line south; Norrköping and nearby Linköping also have smaller airports with limited connections. Sweden belongs to the Schengen area, so technicians travel from India on Schengen visas, applied for once the call is confirmed or expected with reasonable certainty. Terminal access, including the ISPS-controlled container and oil berths, is arranged by the ship's agent, who submits the team's names to the terminal operators before arrival.

• 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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