Thickness Measurement at Hammerfest for LNG Carriers, Offshore Supply Ships and the Barents Sea Fleet

Inspection services for ships at Hammerfest

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

Where ships are gauged at Hammerfest

The supply bases are where offshore vessels spend their time in port, loading deck cargo, drilling fluids, fuel and water between trips. Gauging on board is planned with the vessel operator around the loading programme: deck plating and cargo rails while cargo is lifted elsewhere on deck, engine-room piping at any time, and tanks once they have been emptied and cleaned. The bases handle drilling-fluid bulk and waste reception, which makes tank preparation possible within a normal port stay, especially when a crew change or a weather hold stretches it.

At Melkøya the LNG terminal sets the rules. Any work on a carrier at the jetty is agreed in advance with the terminal and the ship, uses equipment the terminal accepts, and is confined to spaces outside the cargo containment system: ballast tanks, voids, deck structure away from hazardous areas and the engine room. Hammerfest has no dry dock for large ships. Fishing vessels and workboats use slipway yards elsewhere in Finnmark and Troms, while offshore vessels and LNG carriers dock at larger yards further south or abroad, and readings taken in Hammerfest feed their steel estimates.

• Offshore supply bases — tank, deck, cargo-rail and piping gauging on PSVs and standby vessels between Barents Sea trips.
• Melkøya LNG jetty — ballast tank, void and deck gauging on LNG carriers within terminal permits, cargo containment excluded.
• Town harbour and fish plant quays — fish-hold and hull readings on trawlers and coastal fishing vessels after landing.
• Coastal express and cargo quays — short machinery-space and deck checks during scheduled calls.
• Berths used during weather holds — fuller tank programmes on offshore vessels kept in port by Barents Sea storms.

Petroleum regulation, gas terminals and Arctic conditions at Hammerfest

Petroleum activity in the Barents Sea falls under Havtil, the Norwegian Ocean Industry Authority, and vessels serving the installations meet the field operators' own requirements on top of class and flag. Foreign ships, most LNG carriers among them, are subject to Paris MoU port state control by the Norwegian Maritime Authority, and ship traffic along the northern coast is watched from the vessel traffic service centre at Vardø. LNG carriers are also vetted by their charterers and screened by the terminal, so a ship with documented ballast tank and hull condition faces fewer surprises when inspectors and vetting officers come aboard.

The Arctic climate leaves its own marks on steel. Ice on decks and railings is cleared by hand, and the scraping and hammering involved chips coatings and starts corrosion at deck fittings, railing stanchions and hatch edges. Winterisation adds heat-traced pipes, covered walkways and enclosed deck areas, under which wastage can go unnoticed until someone measures it. Supply vessels that have moved north from North Sea work can therefore develop corrosion in places their owners are not used to checking, and a first set of readings after a winter in the Barents Sea is often revealing.

Wherever a ship is outside a sulphur emission control area, the global 0.50% sulphur cap applies, and many of the ships calling at Hammerfest meet it with an exhaust gas cleaning system rather than compliant fuel. Scrubber wash-water piping, the overboard discharge and the hull penetration around it corrode quickly in service, especially on open-loop systems, and are worth adding to the gauging scope.

How a thickness measurement job runs at Hammerfest

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

Hammerfest has a small regional airport with domestic connections, and Alta Airport, with direct flights from Oslo, is within driving distance; the team usually flies to one of the two and continues by road. The supply bases and the Melkøya terminal are ISPS facilities, and the LNG plant applies its own induction and equipment checks, so the operator or the ship's agent submits the team's details well before arrival. Norway is in the Schengen area, and the technicians travel from India on Schengen visas planned against the vessel's schedule.

• 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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