Ultrasonic Thickness Gauging for Ships in Xiamen

Inspection services for ships at Xiamen

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

Berths, anchorages and yards around Xiamen Bay

Xiamen work is done alongside or at anchor far more often than in dock. The container terminals at Haicang give access to deck structure, coamings and piping on container ships, and to ballast tanks when the ship's stay and ballast plan allow. Bulk berths around the bay allow hold gauging after discharge, while ro-ro ships release their vehicle decks as cargo moves. At anchorage, ships waiting in ballast can open holds and tanks for pre-purchase, on-hire or pre-docking gauging, with the team boarding by launch arranged through the agent. Inside the bay the water is sheltered, so outside the monsoon and typhoon periods launch transfers to ships at anchor are usually straightforward.

Docking work takes place in the repair yards around Xiamen and elsewhere on the Fujian coast. For short-sea and feeder owners, the value of a Xiamen gauging often lies in the sequence: readings taken at berth or anchorage define the steel renewal scope, the yard prepares accordingly, and the survey gauging in dock then confirms and completes the picture. Ships that trade between Xiamen and the Pearl River Delta can equally carry the Xiamen readings to a yard further south.

• Haicang container terminals — container berths on the mainland side of the bay; deck, coaming and scrubber discharge lines, plus ballast tanks when the stay and ballast plan allow.
• Bulk and general cargo berths around the bay — coal and raw-material carriers of handy and Supramax size; hold plating, hopper slopes and hatch covers once discharge ends.
• Xiamen Bay anchorages — sheltered water for launch boarding outside the typhoon and monsoon periods; ships in ballast measured ahead of a sale, a charter or a yard visit.
• Ro-ro berths — car deck, ramp and stern door gauging on ro-ro ships and car carriers as decks become free during cargo work.
• Fujian coast repair yards — dockings for short-sea and feeder owners, with renewal survey gauging and re-measurement of steel the yard has replaced.

Coastal rules and short-sea trading in Fujian

Foreign ships at Xiamen are inspected under the Tokyo MoU by China's Maritime Safety Administration, and the Fujian coast is inside China's domestic emission control arrangements, which also limit where open-loop scrubbers may discharge. Smaller feeder and short-sea ships seldom carry scrubbers at all, so their inspection needs centre on hull structure, tanks and piping rather than exhaust-cleaning systems; the larger container ships calling at Haicang are where scrubber piping becomes part of the scope.

Short-sea trading is hard on ships in ways that reward regular gauging. Frequent port calls and ballast changes, cargo handling at every stop and a warm, humid climate all speed up corrosion in ballast tanks, hold structure and deck fittings. Ships in the trade between Fujian, the rest of the China coast and Southeast Asia also face scrutiny from charterers and port state inspectors, who look closely at hatch covers, ballast tank coatings and fire main condition. Feeder ship thickness measurement between surveys lets the owner plan steel and piping renewal into the next docking instead of reacting to a deficiency raised at the gangway.

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

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

Arrival is at Xiamen Gaoqi International Airport — or the new Xiang'an airport once it takes over from Gaoqi — normally via a Chinese or Southeast Asian hub. The ship's agent obtains passes for Haicang and the other port areas and books the launch for any anchorage boarding, weather permitting. For an India-based team, the Chinese business visa and its supporting invitation letter are the step that needs most notice, so applications are made as soon as the berth, anchorage window or dock date is fixed.

• 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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