Ship Thickness Gauging on the Flensburg Fjord: Coasters, Cargo Ships and Ro-Ro Tonnage

Flensburg: a border fjord with a working harbour

The Flensburg Fjord runs inland from the western Baltic between the German shore of Angeln and the Danish shore of Sønderjylland, narrowing as it goes until it ends at the city. The border follows the water for much of the way, so a ship bound for Flensburg passes Danish coastline to starboard and German coastline to port. The water is sheltered, tidal range in the Baltic is small, and there are no locks or bridges to pass, which makes the fjord easy to reach for coasters and short-sea traders. Its length, though, means a call at Flensburg is a deliberate destination rather than a stop on the way somewhere else, and ships come in for a cargo, a lay-by or a yard appointment, then head back out the way they came. In strong easterly weather the outer fjord can be lively, while the inner harbour stays calm.

Commercial traffic is modest and regional. Small dry-cargo ships bring in feed, fertiliser and building materials and take out grain from the farms of northern Schleswig-Holstein, working the quays of the inner harbour. The Flensburger Schiffbau-Gesellschaft (FSG) on the eastern shore has built ro-ro and ro-pax ships for European and overseas operators for decades, and after an insolvency the yard changed owner in 2025. Passenger traffic is mostly excursion boats working the fjord in the summer months. The city's long maritime history shows in its historic harbour, where traditional ships and museum vessels lie alongside, and several of the traditional ships based here still take guests to sea each season. Workboats, tugs and small service craft based in the harbour complete the picture.

For gauging, the rhythm is set by the cargo. A coaster may be alongside for a day or less, discharging with grabs or by conveyor and then loading the next cargo for another Baltic or North Sea port. The interval between cargoes, when holds are empty and swept, is the useful window, and the crew's preparation determines how much of it goes on measurement. Superintendents of these ships are often managing several small vessels at once, sometimes from Germany, the Netherlands or Denmark, and value a defined scope finished inside a single call. Winter brings fewer cargo calls but more idle ships, including traditional vessels in lay-up. Harvest season works the other way: when grain starts moving in late summer, berths fill and turnarounds shorten, so a superintendent who wants a hold gauged then should tell us early.

Thickness measurement through the survey cycle at Flensburg

Every renewal survey asks for more thickness measurement than the last, and for oil tankers, chemical tankers and bulk carriers the ESP Code adds close-up survey on top. The table is the usual shape of the work; the class rules and the surveyor set the exact extent, which is why the measurement plan for a job at Flensburg is agreed in writing before mobilisation.

Typical gauging jobs at Flensburg

Flensburg work is mostly short, focused gauging on small cargo ships, scoped by a superintendent who already knows which part of the ship is the concern, often from the last class report or a port state inspection. Holds and hatch covers come first on ships in the fertiliser and feed trades, ballast tanks on ships approaching an intermediate or renewal survey. The crew's part is to have holds swept, tanks emptied and ventilated, and permits ready before the team boards. Occasional longer jobs come from sales, from ships returning to service, and from traditional ships preparing for a slipping. Examples:

• A coaster after discharging fertiliser: hold frames, lower brackets and tank-top plating gauged before the hold is washed and reloaded with grain.
• A general cargo ship awaiting its next fixture at a lay-by berth: hatch cover panels, coamings and compression-bar seats measured and checked for cracks.
• Pre-purchase gauging of a small bulk carrier for a Scandinavian buyer: holds, ballast tanks and deck plating measured in a single stay alongside.
• A steel traditional ship in winter lay-up: hull plating and frames gauged from inside the hull to plan plate renewals before the next slipping.
• A short-sea ship ahead of an intermediate survey: selected ballast tanks gauged in Flensburg so the steel estimate is ready for the docking yard.

Who does the work, and when class approval applies

The inspection team is mobilised from India for each job; nobody is stationed at the port, so mobilisation is planned against the vessel's schedule and visa lead times. Our founder and Responsible NDT Level III, who holds ASNT NDT Level III in UT, RT, MT, PT and VT and has over eleven years of international field experience, plans and supervises the work. Technicians are certified under the company's written practice to ASNT SNT-TC-1A, and the company holds ISO 9001 and ISO 14001 certification.

Thickness measurement that a classification society credits to a class survey has to be carried out by a firm approved by that society under IACS UR Z17. Atlantis is in the process of obtaining UR Z17 approval from DNV, Lloyd's Register and ABS. Until a certificate is issued, the readings we take are for the owner's own decisions, not for credit to a class survey, so tell us the vessel's class and the survey due when you enquire and we set the scope for the right purpose. Owner's and charterer's condition gauging, pre-docking steel estimates, pre-purchase and on-hire or off-hire gauging, and scrubber and piping condition checks between surveys do not need class approval.

Frequently asked questions