Ship Construction and Ship Maintenance
Scope
Ship Construction and Ship Maintenance tests hull structure, watertight integrity, tank boundaries, corrosion control, hatch covers, planned maintenance and survey requirements. The exam expects you to know which structural member does what and how wastage affects strength.
Core rules
- The keel is the backbone; frames give transverse shape; longitudinal stiffeners resist bending; bulkheads divide compartments and limit flooding.
- The collision bulkhead is forward and watertight; double-bottom tanks protect the inner bottom and hold ballast or fuel.
- Watertight doors must be operable locally and from the bridge where required; they are not to be wedged open.
- Coating systems require correct surface preparation; incompatible coatings cause blistering and detachment.
- Planned maintenance records and survey reports must be factual, dated and signed.
Worked example
A deck plate was 12.0 mm new and the allowable wastage is 20%. Minimum acceptable thickness = 12.0 × 0.80 = 9.6 mm. A gauged reading of 9.4 mm is below the limit, so the plate must be renewed or repaired, not simply painted. A reading of 9.8 mm is within limit but should be recorded and monitored.
Traps
Confusing a stringer with a girder, placing the collision bulkhead amidships, and accepting a visual inspection instead of gauging are common mistakes. Do not assume a coating hides wastage.