Thickness Measurement for Ships at Portland Port and Portland Harbour

Inspection services for ships at Portland (Dorset)

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

Berths, anchorages and repair support at Portland Port

Portland describes itself as suited to both long and short lay-ups and to repairs afloat: engine overhauls, maintenance, refits and the related onboard work, with local marine engineering firms on hand and owners free to bring in their own contractors through the ship's agent. For gauging, that means a ship can stay alongside or at anchor long enough to open tanks one after another, gas-free them properly and gauge each in full, rather than taking the spot readings that a short call allows. Staging and lighting are arranged with whichever contractor is already working on the ship.

There is no drydock at Portland, so bottom shell, sea chests and the stern area can be reached only from inside the double bottom and engine room. When a docking is needed, owners send ships to Falmouth, to a Continental yard or further afield, and the readings taken at Portland become the specification that yard works to. Ships at anchor in the harbour are reached by launch arranged by the agent, and the breakwaters keep the water calm enough for boarding in most conditions; outside them in Weymouth Bay, the weather has more say in whether a transfer goes ahead.

• Deep-water cruise berth — piping, tank and structural readings on cruise ships during a call or a longer technical stay.
• Quay berths — full tank, hold and deck gauging on ships in lay-up or under repair alongside.
• Inner harbour anchorage — launch-borne gauging on ships laid up or awaiting repairs, sheltered by the breakwaters.
• Outer harbour anchorage — deeper water for the biggest ships, where tanks can be gauged in rotation over several days.
• Bunker calls at the berths or anchorage — targeted deck, air-pipe and ballast tank readings during the fuelling stop.
• Weymouth Bay — boarding by launch for ships waiting outside the harbour, in settled weather.

Lay-up, reactivation and port state control at Portland

A ship laid up at Portland has not left the regulatory system. Its class and flag set conditions for lay-up, and before it trades again it has to complete whatever surveys were postponed or have fallen due, which often means a docking survey, an annual survey and, on an older ship, gauging the class surveyor will expect to see. Corrosion carries on during lay-up, particularly in ballast tanks with failing coatings, in sea-water systems left stagnant and in deck structure that nobody is chipping and painting, so a baseline taken early in the lay-up and a second set before reactivation tell the owner how fast it is progressing.

Port state control at Portland, as across the UK, is carried out by the Maritime and Coastguard Agency within the Paris MoU, and a ship coming out of a long lay-up is a natural candidate for close attention. The harbour also sits beside the Jurassic Coast, a natural World Heritage Site, and the port expects contractors to keep debris and run-off out of the water. Inspection work leaves little behind, but coating removed to reach bare steel is gathered up, and any finding that leads to hot work is planned with the port and the repair contractor before it starts.

Ships trading to Portland (Dorset) 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 Portland (Dorset)

The sequence for a thickness measurement job at Portland (Dorset) is short and written down, so the yard, the surveyor and the superintendent know who arranges what.

Bournemouth Airport and Exeter Airport are the nearest with international flights, though most teams fly into Heathrow and take the train from London to Weymouth, crossing the causeway to Portland by road. Port access is controlled; the ship's agent arranges gate passes for berth work and launches for anchorage work. Technicians come from India on UK visas, and because lay-ups and repairs are usually planned weeks ahead, there is normally time to have visas in hand before the ship arrives.

• 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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