Ultrasonic Thickness Measurement for Ferries, Ro-Ro and Fishing Vessels at Hirtshals

Inspection services for ships at Hirtshals

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

Gauging locations in Hirtshals harbour

Most gauging at Hirtshals is done afloat at the ship's own berth. The ferry terminals have linkspans and stern-ramp berths where a ro-pax ship can lie overnight or during a gap in the timetable; with vehicle decks empty, the team can work along the lanes, examine door and ramp structure and enter tanks the crew has prepared. Freight ro-ro ships on the Faroes and Iceland service lie longer at each call, which suits a defined set of ballast tanks or a deck section. In the fishing harbour, trawlers lie at the landing quays, and the realistic window is the day between landing and sailing, with holds already washed and open.

Repair workshops in the harbour serve the fishing fleet and the ferries, but for a full docking ships generally go to larger yards. In North Jutland those are at Skagen, where fishing vessels are built and repaired, and at Frederikshavn; ferries on the Norwegian routes are also docked in Norway, Poland or elsewhere, depending on the owner's contract. Gauging at Hirtshals before a docking lets the owner send the yard a steel estimate and decide what can be renewed during the stay. Anchorage work off Hirtshals is seldom realistic because the open coast gives little shelter, so ships that must be measured afloat are measured alongside.

• Ferry berths with linkspans — car-deck lanes, bow and stern doors, ramp hinges and prepared tanks on ro-pax ships lying overnight or between sailings.
• Ro-ro freight berths — ballast tank, tank-top and deck gauging on freight ships serving the Faroe Islands and Iceland during their longer calls.
• Fishing harbour landing quays — fish-hold, trawl-deck and fuel-tank readings on trawlers between landing and sailing.
• Quays used by the harbour's repair workshops — piping and structural checks during afloat repairs, where readings decide which sections to renew.
• Docking yards at Skagen and Frederikshavn — slipway and dock gauging on fishing vessels and smaller ships sent there for repair.

North Sea fisheries, Norwegian trades and inspection rules

Denmark carries out port state control under the Paris MoU through the Danish Maritime Authority, and the ro-pax ferries from Hirtshals also fall under the EU regime for inspecting passenger ro-ro ships and high-speed craft on regular services. Under that regime the ships are inspected at fixed intervals in service, and structural or door findings from those visits often lead to a request for readings. Emissions rules divide the routes: Norway and Iceland apply the EU ETS for shipping and FuelEU Maritime as EEA states, while the Faroe Islands are outside both the EU and the EEA, so a crossing to Tórshavn counts as a voyage to a third country.

Fishing vessels belong to a different regulatory world. They sit outside the Enhanced Survey Programme that governs tankers and bulk carriers, many Danish trawlers are not classed by an IACS society, and their inspection programme comes from the Danish Maritime Authority's rules for fishing vessels, the insurer and the owner's own maintenance plan. Insulated fish holds, refrigerated seawater tanks on pelagic ships, trawl winch foundations and the stern area where gear is hauled are the typical concerns. On the North Atlantic ferries, bow structure and forward shell plating take repeated slamming in winter, and owners want that area measured before it turns up as a finding.

Ships trading to Hirtshals 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 Hirtshals

A gauging job at Hirtshals 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.

Aalborg Airport is the nearest airport, with connections through Copenhagen and other European hubs, and Billund is an alternative; from either, the team continues by road to Hirtshals. Denmark is a Schengen state, so technicians travelling from India need Schengen visas, and we apply as soon as the ferry operator or trawler owner gives us a date. Ferry terminal access is controlled under ISPS and arranged through the operator or the ship's agent; access to the fishing harbour is agreed with the vessel owner.

• 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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