By Capt. Neeraj Bharti, Founder, Master Mariner · Published · 2 min read
Mopping, spot cleaning and drying: the manual finish that decides the inspection
Machine washing gets a tank most of the way to clean. The last part, the part the inspector sees, is done by hand. Puddles in the suction well, a film of oil behind a frame, a wet bottom that should be dry: these are what fail inspections after a changeover, and they are all fixed by manual finishing.
Stripping
Before anyone mops, the tank must be stripped as dry as the system allows. Good stripping reduces the water and residue left for manual work. Check that stripping suctions are clear and that the trim helps water run to the suction.
Spot cleaning
Walk the tank with a good torch after washing and look in the places machines miss:
- Behind longitudinal frames and under stringers
- Around bellmouths and in suction wells
- On and between heating coils and their supports
- Ladders, platforms and their undersides
- Corners and welds on the tank bottom
Hand-hose or wipe any residue found. Spot cleaning a few areas is far quicker than repeating a machine programme.
Mopping
Mop standing water and wet residue from the tank bottom, suction wells and any pockets in the structure. Use clean mops and lint-free material so you do not leave fibres behind, which can themselves become a contamination finding.
Drying
Tanks should be dry, not just "no puddles". Ventilation fans speed up drying. In humid conditions, drying takes longer; plan for it. Water left in a tank is a quality risk for many clean grades and can cause rust that sheds particulates.
Pre-inspection
Before the inspector arrives, a responsible officer or supervisor inspects every tank to the same standard: torch, white rag, and attention to the places inspectors look first. Photograph each tank. See failed tank inspection after a changeover.
Safety
Manual finishing means entry into tanks that recently held cargo. Gas-freeing, atmosphere testing, permits, communication and a standby person are required for every entry.
See the DPP to CPP changeover guide for the full sequence.
How Cleanship helps
Our teams carry out manual finishing, mopping, drying and pre-inspection as part of changeovers or as a final finishing crew before inspection, from our bases at Fujairah and in India. See our DPP and CPP tank cleaning service or contact us.
Sources & further reading
Frequently asked questions
Why is manual finishing important after tank washing?
Machines miss areas behind structure, in suction wells and on coils, and leave water in tank bottoms. Inspectors look exactly there, so manual spot cleaning, mopping and drying decide most inspections.
How dry should cargo tanks be before inspection?
Dry, not just free of puddles. Standing water and wet residue are inspection failures and a quality risk for many clean grades.
What should be used for mopping cargo tanks?
Clean mops and lint-free material, so no fibres are left behind to become a contamination finding.
Should the crew pre-inspect tanks before the surveyor?
Yes. A pre-inspection to the inspector's standard, with photographs, catches problems while they are still quick to fix.
- mopping cargo tanks
- drying tanks tanker
- spot cleaning tanks
- manual tank cleaning finish
- tank inspection preparation
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