Structure & Stability Flashcards
Topside Integrity
It is important to evaluate various aspects of a ship’s structure for vulnerabilities that could affect its stability. Conduct a thorough examination of a ship’s topside equipment and structural components.
Rails and Bulwarks
Ensure guardrails or bulwarks are at least 1meter (m) from the deck; a lesser height is acceptable if the administration is satisfied there is adequate protection.
The opening below the lowest course of the guardrails cannot exceed 230mm, or 9 inches. The other courses cannot be more than 380mm, or 15 inches, apart.
This comes into play if any guardrails are missing or damaged from cranes
Structural Integrity
Examine the structural integrity of the hull, determine cause of damage or deterioration and request a class report if necessary.
Assess the severity of any of the following, as it could impair the ship’s seaworthiness:
• Fractures • Corrosion • Excessive wastage • Pitting • Excessive doublers, a piece of steel welded on top of the hull to cover or conceal a hole • Postage stamp inserts, Inserts larger than 12”x12” are allowed per International Association of Classification Societies (IACS) Recommendation 47.
• Cement boxes • Soft patches • Welding burn marks or other evidence of recent repair work • Frame pulling away • Holes in main decks • Leaks/patching on ballast tanks • Bulkheads/decks excessively warped.
Paint/Flammable Liquid Locker
- Depending on the size of the locker, determine what appropriate fire extinguishing arrangement is required and properly installed. Refer to reference (e), SOLAS, for additional guidance. Be mindful of the hazards with each fire-extinguishing medium, or foam.
- Verify electrical installations are explosion-proof with no exposed wiring and ground protection in place.
- Proper ventilation is present. Ensure the motor, if mechanical, is certified safe or located outside the space.
- Contents of the locker are properly stored to prevent spillage and do not directly block access to fire-extinguishing medium. If multiple chemicals/paints are located within the same locker, ensure proper segregation is in place.
Oxygen/Acetylene Storage Lockers
- Oxygen and acetylene tanks are typically kept in a locked locker attached to the superstructure on the back deck. They are not stowed inside the ship due to their volatile capabilities. The lines are permanently affixed and lead to the workshop in the Engine Room. Look for excessive quantities of oxygen and acetylene. Maximum quantities allowed in the U.S. are contained in §§ 147.70 and 147.85 of reference (mm), Shipping, 46 CFR. The need to carry excessive quantities potentially indicates a more serious maintenance problem onboard the ship.
- Ensure bottles are secured to prevent falling and that valve protection caps are in place on bottles that are not in service. Proper ventilation in the space prevents accumulation of vapors and decreases the possibility of excessive heat exposure to the bottles.
Mooring Arrangements
Inspect parts of the anchor and windlass:
- Foundations: Look for cracks around the base of the anchor assembly, bench framing members, or missing parts.
- The majority of anchor windlasses on deep draft ships are hydraulically- driven. The hydraulic pumps are typically inside the bosun stores. Verify guards are in place over moving parts and containment of oil is in the proper storage/service tank.
- Ensure brake pads on the anchor windlass are sufficient. There is going to be wear on the pad or it might be covered in paint. The brake pad needs to be replaced prior to metal on metal contact which could result in a runaway anchor.
- Verify no missing or wasted deck fittings and components of the anchor assembly.
- If the anchor windlass is electrically-driven, ensure all electrical components are secure and properly grounded, meaning no exposed wiring. If hydraulically-driven, ensure there is no excessive leakage that would prevent normal working operations.
- Examine the exposed anchor chain for wastage. Keep in mind, a single link cannot be replaced. If a link has been determined wasted or unacceptable, the entire shot needs to be replaced at the kenter shackle.
- Verify primary containment around all exposed hydraulic piping and that containment is provided with a mechanical plug, to allow for the drainage of any accumulated water.
- If the anchors are deployed, ask the Ship’s Security Officer (SSO) if anchor guards are required to be installed at Security Level 1, or current Security Level, while in port. Mooring winches/capstans:
- Normally, the winches are incorporated with the anchor windlass on the bow of the ship. However, they are standalone on the stern. Check for the same criteria as the anchor windlass.
- Condition of the mooring lines. Ensure the eyes are braided and that there are no knots tied in the lines.