The Draft Survey is a technique based on Archimedes’ principle to calculate the weight of cargo loaded or unloaded to or from a ship from measurements of changes in its displacement.
Seatech Marine & Cargo Surveys has large experience in performing draft surveys, as it is very required by our clients. We have acting different times on behalf of Owners, Charterers or any other interested party.
In the top of our priorities list, we have the quality of our services by using our own calibrated equipment, we assure that the findings are as accurate as possible.
We start our attendance for Draft Survey at berthing time, jointly reading vessel’s initial draught marks. After draught reading, our attending Surveyor obtain samples of water in which the vessel is floating at, the time at which the draught marks are read.
The total deductible weights on board and all draft marks readings are measured and calculated by us in accordance with data supplied by the vessel (hydrostatic and tanks calibration tables) prior to commencement of loading/discharging and on completion of loading/discharging. By using international guidelines, our Surveyors consider the water density of vessel’s gateway, changes on ballast quantities, consumption of vessel’s bunkers and fresh water, performing corrections proper corrections for trim, list and deflection (hog/sag).
At completion of survey, a Draft Survey Report is issued aboard and afterwards a complete Survey Report is sent to our clients, recording the full data and calculations used to obtain the cargo loaded/unloaded quantity.