What this survey covers.
Draft surveys estimate cargo weight from changes in the vessel’s displacement before and after loading or discharge. Readings and calculations depend on vessel condition, water density and relevant corrections.
Typical inspection scope
- Arrival and departure draft readings
- Quantity and displacement calculations
- Supporting survey documentation
How the work is carried out
- 01
Confirm vessel details, cargo operation and required attendance.
- 02
Observe draft marks, tank conditions and water density as applicable.
- 03
Calculate displacement differences with relevant adjustments.
- 04
Prepare a report of readings, assumptions and calculated quantities.
Before the survey & typical deliverables
What to prepare
- Vessel name, IMO number and anticipated berth or anchorage
- Cargo type and expected start and completion times
- Hydrostatic particulars and relevant tank information when available
What the report may include
- Recorded initial and final draft observations
- Displacement and cargo-quantity calculation summary
- Assumptions, corrections and any observed constraints
Important limitations: Draft survey results are estimates affected by sea state, access to draft marks, water density, vessel data, trim and tank-condition accuracy.
Exact attendance, methods and deliverables are agreed with the operations team for each assignment.
Who this service is for
Bulk cargo shippers, receivers, charterers, vessel operators and trading companies.
Frequently asked questions
What does a draft survey determine?
It estimates the weight of bulk cargo loaded or discharged using the change in vessel displacement.
When should a draft survey be arranged?
Typically before and after cargo handling. Exact attendance times should be coordinated with the terminal and vessel.
Can a draft survey support a quantity discrepancy investigation?
A documented survey may provide evidence to assist the parties reviewing a quantity discrepancy. The conclusion depends on the survey scope and records.
Enquiries are welcome for Colombo, Galle, Trincomalee, Hambantota and selected anchorage attendance, subject to operational confirmation. Exact deliverables, credentials, regulatory acceptance, cost and attendance are confirmed for each assignment.
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