Ultrasonic Thickness Measurement for Ships at Concarneau

Inspection services for ships at Concarneau

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

Where gauging can be done at Concarneau

The shipyard's berths and repair quays are the main place for thickness work. A vessel in for repair afloat has its tanks emptied and ventilated by the yard as part of the programme, and hull plating below the waterline can be measured on the sections exposed by the yard's lifting and dock arrangements. The superintendent and the yard agree the sequence, and the technicians measure compartments as they are released so renewal decisions are taken early. Steel found below the owner's allowable diminution is marked in the plan before the cutting begins.

At the fishing quays a seiner or trawler lies alongside between voyages, and its decks, fish holds, fuel and ballast tanks and accessible piping can be gauged. The commercial quay offers the same for small coasters. Because the harbour is small, access to a vessel is usually a matter of a gangway rather than a launch. For ships waiting outside the harbour for a berth or a tide, a launch can be arranged by the agent or the harbour authority. The sea state in the bay is mostly manageable, though Atlantic swell can arrive in winter.

• Shipyard berths and repair quays — hull, tank and piping gauging on patrol vessels, tugs, workboats and fishing vessels in repair.
• Fishing quays — tuna seiner and trawler plating, fish hold, fuel tank and piping readings between voyages.
• Commercial quay — hold, coaming and hatch cover gauging on small coasters during discharge or loading.
• Harbour anchorage and outer berths — launch-served readings on vessels waiting for a quay space or the tide.
• Island ferry berths — deck and tank checks on small passenger craft during the off-season.

Regulation and the fishing and patrol fleets

France applies Paris MoU port state control, and the Centres de sécurité des navires of the French maritime administration oversee safety on French-flag fishing vessels and coastal craft. A tuna seiner returning from months at sea faces a thorough check of its hull and systems, and an owner who has measured the plating in advance can plan repair work on his own timetable. Foreign-flag ships calling in the harbour follow the same risk-based targeting as at any Paris MoU port.

Patrol vessels and naval-style craft built in Concarneau are delivered to government customers under their own acceptance and class arrangements, and the shipyard's quality control and the customer's inspectors remain the route for that work. For owners of fishing vessels, thickness readings support voluntary classification and the decision to renew steel. EU ETS and FuelEU Maritime affect larger ships on EU voyages, and the EU Ship Recycling Regulation's Inventory of Hazardous Materials applies to ships calling at EU ports. Older hulls on long voyages are the ones where measured steel is most valuable.

Wherever a ship is outside a sulphur emission control area, the global 0.50% sulphur cap applies, and many of the ships calling at Concarneau 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 Concarneau

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

Quimper-Cornouaille airport, near Concarneau, has connections to Paris, and from India the practical route is a flight to Paris Charles de Gaulle followed by a domestic flight or a train towards Quimper and a road transfer to the port. The shipyard or the ship's agent arranges access to the quays and the repair berths. France is in the Schengen area, so every technician needs a Schengen visa, which we apply for once the yard stay or the landing period is firm, together with an invitation letter from the owner or yard naming the vessel.

• 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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