Ship Piping Inspection · Amsterdam, Netherlands
Cargo and Ballast Pipe Gauging for Product Tankers Loading at Westpoort
Amsterdam is one of Europe's gasoline blending and storage centres, so product tankers load here all year and lie in the western basins between parcels. That makes it a natural place to check the piping that carries the cargo and the ballast: deck lines, manifolds, pump-room pipework and the ballast mains. We gauge pipe walls by ultrasonic thickness measurement, compare each reading with the minimum wall, and report spool by spool. The team is mobilised from India to the tanker, and the readings are taken during loading or at a lay-by berth.
Deck lines checked between parcels
Manifold crossovers, deck cargo lines and their supports can be reached while the ship loads and discharges. Gauging the outside of bends, the runs below valves and the pipe resting on supports does not interrupt the cargo operation.
Pump room and stripping lines
The pump room holds the pipework most exposed to water, residues and cargo changes. Once the room is ventilated and certified for entry, suction lines, stripping lines and pump casings are gauged against the minimum wall.
Ballast mains in waiting time
Ballast piping runs through void spaces and along the tank tops, where sea water sits at low points. A lay-by stay gives the time to examine the mains, branches and valves, and to measure them where the corrosion is most likely.
Why does a product tanker's piping get attention at Amsterdam?
Gasoline arrives and leaves in parcels, and a tanker that trades from Amsterdam may carry gasoline blending components, finished gasoline, gasoil and other clean products in the same year. Each change of cargo is followed by line flushing, tank washing and a period of exposure to water and cleaning chemicals, and every cycle works on the same bends, valves and low points. Vetting inspectors and charterers look closely at the pipework because a leaking cargo or ballast line is a cause of pollution as well as of operational delay.
The call itself is longer than at many ports. Ships wait for blending to finish, for a berth or for a cargo to be confirmed, and that waiting time is the window technical managers use. A tanker owner who sees corrosion on a manifold spool during a vetting inspection will usually want a full set of readings on that system before the ship is back in service.
Mid-life product tankers are the typical customers. Newer ships have coated or lined piping that is still in good condition; very old ships are often at the end of their trading life and are gauged in connection with a sale or a decision about the next renewal. The middle group is the one for which measured wall thickness decides whether lines can run for another survey cycle.
Where the piping can be gauged at the port
Tank terminals in Westpoort apply permit rules, and the manifold, the deck lines and the pipework in the open can usually be examined during cargo operations, as long as the work is cold work and the terminal permits access to the deck. The pump room needs a gas-free certificate and a permit, so we schedule it for a period when cargo operations have stopped and the room has been ventilated. Lay-by berths in the basins and quays at IJmuiden are better suited to long programmes because the ship is not under the terminal's pressure to release the berth.
On offshore and workboat tonnage using the same quays, the piping is mostly sea water cooling, fire main, bilge and fuel lines, and the same method applies. The plan for each ship type differs, but the logic of measuring where wall loss is likely, not at regular spacing, is the same.
- Westpoort loading berths: manifold, deck cargo lines and exposed ballast piping during cargo operations.
- Lay-by berths in the basins: pump room, stripping lines and ballast mains during a longer stay.
- Quays at IJmuiden: sea water, fire main, bilge and fuel lines on offshore and support vessels.
- Yard quay or dock: renewal survey piping checks tied to the TM plan or to a repair specification.
How a tanker piping inspection is scoped
We begin with the system drawings and the previous readings, where they exist, and select the measurement points from them. On a product tanker the typical selection includes each bend and elbow on the cargo and stripping lines, the downstream side of every valve and reducer, the low points at which water collects, and the lengths under pipe supports and in contact with the deck or the tank top. These are the places at which erosion, corrosion and crevice attack combine.
Each location is marked with a grid, usually a few points around the circumference and at an interval along the run, so a reading at the weakest point of the section is not missed. Insulation is removed in the necessary areas by the ship's crew, paint and scale are cleaned to the metal, and the gauge is calibrated on a reference block at the start and at intervals through the job. Where a pipe is lined or coated internally, readings are taken on the metal, not through the lining, with the technique chosen to suit.
Ballast piping gets a separate approach because it lies in spaces that are often tight, poorly lit and wet. We prefer to work during a ballast tank or void space entry that is already planned, so the access is shared and the number of entries is kept low.
What we typically find and how it is reported
On cargo systems the pattern is localised wall loss at the outside of bends, at the first section after a throttled valve and where water lies in a dead leg. Stripping lines and drain lines show the earliest wear because they are small bore, carry residues and are cycled with every cargo. On ballast mains the common finding is wastage at pipe supports, where crevice corrosion starts, and at flange faces and welds that were never coated well.
Each reading is compared with the nominal wall and with the minimum acceptable wall that the class rules or the owner's criteria set for that service and diameter. The report presents the results on isometric sketches and in a table by spool, with a clear note of those at or near the limit. A pipe shop can then work from the document directly: a spool below the limit is replaced, one close to it goes on a watch list with a recommended re-measurement interval.
Where a reading is below the limit and the pipe is carrying cargo or ballast, we report it to the superintendent immediately, so that the line can be isolated and the decision taken without waiting for the final document.
Planning a piping job around a Westpoort call
The sequence follows the cargo. Deck work fits into loading and discharge, and the pump room and the ballast system wait for the gas-free period and the ballast operations. Because the team travels from India, we ask for the likely berth dates and the estimated sailing time as soon as they are known, and for notice of any change to the cargo plan that moves the pump-room window.
Please send the ship's piping plans, the class and survey status, the last thickness report on the lines and the list of systems of concern. The agent arranges the gate pass for the technicians. The ship provides insulation removal, lighting, ventilation and an escort for the pump room, and the terminal grants the work permits for deck work during cargo operations.
How the job runs at Amsterdam
A gauging job at Amsterdam runs the same way whatever the ship type. The sequence below is what the superintendent, the attending surveyor and the yard can expect from us.
- 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.
Who does the work
Atlantis mobilises its inspection team from India to the vessel, for each job. There is no office or agent at the port; the team travels to the ship, which is why the planning step comes first. Work is planned and supervised by our Responsible NDT Level III, the founder, who holds ASNT NDT Level III in UT, RT, MT, PT and VT and has more than eleven years of international field experience. Technicians are qualified and certified under the company's written practice to ASNT SNT-TC-1A, and Atlantis is certified to ISO 9001 and ISO 14001.
Governing codes and standards
- IACS UR P2 (minimum wall thickness of pipes)
- SOLAS Chapter II-2 on fire protection and fire main systems
- MARPOL Annex I on oil pollution prevention in cargo and ballast systems
- Class society rules on piping systems, survey and renewal criteria
- ISO 16809 and ASTM E797 for ultrasonic thickness measurement
What you receive
- Isometric sketches with every measurement point and reading
- Table by spool of nominal wall, minimum wall and measured wall
- Watch list of spools near the limit with a re-measurement recommendation
- Photographs of corrosion, erosion and support-point damage
- Calibration records for the gauge and the reference blocks
Industries served
- MR and LR1 product tankers
- Chemical and parcel tankers
- Gasoline blending component carriers
- Offshore support vessels
- Multipurpose ships with fuel and ballast systems
- Short-sea tankers and bunker barges
Frequently asked questions
Can cargo lines be gauged while a tanker is loading at Westpoort?
Deck lines, the manifold and exposed pipework can usually be examined during cargo operations, because the work is cold and does not touch the cargo. The terminal's permit rules decide, and the pump room waits for a gas-free period. We plan the programme with the superintendent and the terminal in advance.
Why are stripping and drain lines measured first?
Small-bore stripping and drain lines carry residues and water and are used with every cargo change, so they usually show wall loss earlier than the main lines. Finding the weakest small lines gives an early view of the overall condition of the system, and renewing them early is far easier than dealing with a leak.
Can ballast piping be inspected without a separate tank entry?
Often, if the ballast tank or void space is being entered for another purpose, such as a survey or cleaning. We aim to share the access, so the pipework in the same space is gauged during that entry. Where no entry is planned, the inspection is arranged around the next one.
What minimum wall do you compare readings with?
The class rule value for the service and diameter, or the owner's own criteria where they are stricter. The superintendent tells us which applies, and the report shows both the measured wall and the minimum, spool by spool, so the decision to renew or to continue is clearly documented.
Does the piping report help in a vetting inspection?
It gives a documented record of pipe condition that the technical department can show an inspector, with measured data and a plan for any weak spools. We do not state what the vetting result will be, but the record is much more useful than a statement that the lines were checked visually.
Planning a survey or a drydock?
Send the vessel name or IMO number, the class, the survey due and the port. We reply with the scope, the mobilisation plan and a quote for that vessel.
Request a QuoteRequest a ship gauging quote
Send the vessel name or IMO number, the class society, the survey due and the port. We reply with the scope, the mobilisation plan and a quote for that vessel.
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