This article provides general marine survey guidance. Editions, applicability and interpretations may change; always confirm the governing flag, class, contract and project requirements.
Imbalance
This is a practical control point in the survey programme. Project teams should define the expected evidence, responsible party and review basis, then keep the vessel condition traceable while the 1 stage is completed.
Misalignment
This is a practical control point in the survey programme. Project teams should define the expected evidence, responsible party and review basis, then keep the vessel condition traceable while the 2 stage is completed.
Mechanical looseness
This is a practical control point in the survey programme. Project teams should define the expected evidence, responsible party and review basis, then keep the vessel condition traceable while the 3 stage is completed.
Good survey evidence connects the reading to the exact vessel condition in which it was captured.
Resonance
This is a practical control point in the survey programme. Project teams should define the expected evidence, responsible party and review basis, then keep the vessel condition traceable while the 4 stage is completed.
Rolling-element bearing indicators
This is a practical control point in the survey programme. Project teams should define the expected evidence, responsible party and review basis, then keep the vessel condition traceable while the 5 stage is completed.
Gear-related response
This is a practical control point in the survey programme. Project teams should define the expected evidence, responsible party and review basis, then keep the vessel condition traceable while the 6 stage is completed.
Hydraulic or aerodynamic excitation and cavitation
This is a practical control point in the survey programme. Project teams should define the expected evidence, responsible party and review basis, then keep the vessel condition traceable while the 7 stage is completed.
Why no pattern should be diagnosed from one plot alone
Vessel behaviour is influenced by structure, machinery, load, speed, environment and human use. The strongest diagnosis considers how those factors changed when the symptom appeared instead of relying on a single overall value.
PRACTICAL TAKEAWAY
Settle the basis before measurement begins.
The strongest vessel surveys start with an agreed technical question, a controlled operating matrix and clear reporting responsibility. That discipline makes the final evidence easier to trust and act upon.