Rudder and Sea Chests (Sea Chests and Sea Valves)
Rudder, sea-chest and shell-valve examinations follow UR Z3/class Rules and surveyor scope; opening extent and IWS/EDD alternatives do not follow a universal instruction.
Operational Explanation
Rudder, sea-chest and shell-valve examinations follow UR Z3/class Rules and surveyor scope; opening extent and IWS/EDD alternatives do not follow a universal instruction.
Regulatory Reference
IACS UR Z3 Rev.8, applicable class Rules and attending surveyor.
Scope of Application
Out-of-water access is the most complete opportunity; valve/cock opening frequency and consecutive-IWS alternatives follow Rules and approved arrangement.
Procedure / How to Complete It
- Prepare access and examination scope.
- Measure rudder clearances as required.
- Open/examine sea valves/chests where required.
- Use alternatives only with formal approval.
- Perform functional/leak tests after maintenance.
Practical Example
A valve is opened within the required Special Survey extent, not necessarily at every docking by a page rule.
What Typically Goes Wrong
Saying necessarily dry dock or always open every sea chest/valve while ignoring surveyor and approved IWS/EDD.
Common Mistakes Mistake Library
| Mistake | Consequence | How to Avoid It |
|---|---|---|
| Saying necessarily dry dock or always open every sea chest/valve while ignoring surveyor and approved IWS/EDD. | Non-compliant decision or treatment | Follow the approved arrangement and applicable sources |
What the PSCO Checks
Operational Tips
- Separate current requirement, class/maker, SMS and voluntary guidance.
- Do not improvise tests, thresholds or intervals.
- Record deviations and corrective action.
Preparation checklist
- UR Z3 scope
- Surveyor direction
- Opening extent
- Post-maintenance test
FAQ
Related Topics
Last substantive revision of this page: 31 August 2026 · page fingerprint b3fe1c633901