Thickness Measurement for Offshore Wind and Energy Vessels at Eemshaven

Inspection services for ships at Eemshaven

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

Quays, terminals and docking options for Eemshaven vessels

Eemshaven is a working port rather than a repair port, and gauging here is done afloat at the quays and terminals. The offshore wind terminals have heavy-load quays where installation vessels and heavy-lift ships load foundations, towers, blades and nacelles. Mobilisation and demobilisation periods, when sea-fastenings are welded on or cut away and equipment is changed, give access to deck areas that are covered by cargo for most of a campaign. Service vessels use their own berths and pontoons, and their port stays are short but frequent, so work on them is planned in packages that each fit one stay.

When a docking is due, Eemshaven vessels go elsewhere. Smaller service and crew vessels can dock at Delfzijl, Harlingen or Den Helder, while large installation vessels and jack-ups need the big docks of yards in Germany, the Netherlands or Denmark, chosen by the owner. Readings taken at Eemshaven before the ship sails let the superintendent go into the docking with a defined steel list and a gauging plan for the remaining spaces. Work on the gas carriers serving the floating LNG terminal is planned with the terminal operator under its gas-safety rules and stays outside the cargo containment.

• Offshore wind terminals — deck plating, crane pedestals, sea-fastening areas and preload or ballast tanks on installation vessels during mobilisation or demobilisation.
• Service vessel berths — gangway and crane foundations, deck structure and ballast tanks on service operation and walk-to-work vessels during crew-change stays.
• Crew transfer vessel pontoons — hull plating, fender zones and weld checks on aluminium and steel crew boats between shifts.
• Multipurpose and heavy-lift berths — hold, tank-top and hatch cover gauging once components have been discharged.
• Lay-by quays — longer gauging programmes on jack-ups, cable layers and offshore ships idle between projects.

Offshore audits, emissions rules and conversions at Eemshaven

Port state control at Eemshaven follows the Paris MoU and is carried out by the Human Environment and Transport Inspectorate (ILT). Many of the vessels working wind farms from here are on long-term charters, and wind farm owners and turbine makers apply their own vessel audits, in which structural condition, lifting equipment records and tank inspection history all count. On jack-up installation vessels, class surveys the legs, spudcans and jacking systems in detail, and the hull and deck structure that carries the jacking and preload forces deserves the same attention from the owner's side.

Regulation is tightening around these ships too. The EU ETS has covered larger cargo and passenger ships since 2024 and is due to take in offshore ships of 5,000 GT and above from 2027, which brings in most installation vessels and many service operation vessels. Operators are answering with methanol-capable and battery-hybrid newbuilds, while older vessels are upgraded or converted, and each upgrade puts new equipment on an existing deck. Measuring the existing structure before a conversion, and checking it again after the first seasons of use, is how owners confirm that the hull is carrying its new role safely.

Ships trading to Eemshaven 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 Eemshaven

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

Amsterdam Schiphol is the main international airport, with onward travel by rail to Groningen and by road to Eemshaven; Groningen Airport Eelde and Bremen Airport are alternatives on some routes. The offshore terminals and the LNG terminal operate under ISPS and their own site inductions, which the ship's agent or the terminal arranges before the team arrives. Technicians come from India on Schengen visas, and because offshore campaign dates move with the weather, we keep in touch with the agent and adjust travel to the vessel's confirmed port stay.

• 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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