Guidance below is for watertight and weathertight doors, it does not cover fire doors. Refer Load Lines Convention.
Surveyor performs the examination and testing, both locally and remotely, of the watertight doors as far as practicable, including all indicators and alarms. When applicable, remote control of doors is checked both individually and for all doors together.
Note: These doors (apart from bow, stem and ships side doors) are those doors allowing access through watertight subdivision bulkheads below the bulkhead deck.
When examining these doors, the Surveyor should verify, as far as possible, the existence of unapproved penetrations in the bulkheads (for temporary electric cables, etc.).
Passenger ship watertight doors
Watertight doors on subdivision watertight bulkheads are to be examined along with the watertight bulkheads themselves. The doors are tested in operation both locally and remotely (usually from the wheelhouse) including open/shut indicators. Any defects should be repaired.
Passenger ship side doors
These doors shall be examined carefully for corrosion, damage or other deterioration to the structure, hinges and locking arrangements. The seals are inspected and the doors hose-tested.
Check for corrosion, damage or other deterioration to the structure, hinges and locking arrangements. Check the integrity of rubber seals and the locking devices. Where open/closed indicators are fitted in the wheelhouse, they must be tested. In case of doubt regarding the effectiveness of these doors, a hose test shall be required.
Ro-Ro passenger and cargo ships
Ro-Ro ship: ship fitted with a loading ramp which enables wheeled vehicles to be rolled-on and rolled-off the ship.
Securing device: a device used to keep the door closed by preventing it from rotating about its hinges.
Supporting device: a device used to transmit external or internal loads from the door to a securing device and from the securing device to the ship’s structure, or a device other than a securing device, such as a hinge, stopper or other fixed device, that transmits loads from the door to the ship’s structure.
Locking device: a device that locks a securing device in the closed position.
OMM: Operating and Maintenance Manual
Check that the operating procedures for closing the shell and inner doors are kept on board and posted at appropriate places.
Check the OMM (when required) for the verification of its approval and of any modification, reported repairs and proper endorsement by operating personnel.
Operation from the wheelhouse, of watertight doors and their position indicators, are to be checked at each survey as well as the operation of the doors on site.
Side doors, stern door, bow door and inner doors shall be examined .Whenever a crack is found in a vital element, an NDE shall be made in the surrounding areas and all similar elements shall be examined. It is reminded that no visible deformations are accepted in these elements.
Hinges, bearings and thrust bearings:
- Clearances are to be measured at annual surveys (where no dismantling is required).Whenever clearances cannot be measured without dismantling, they are to be measured, at least, at the Class Renewal Survey and where the function test is not satisfactory.
- After dismantling, a visual examination of the bearings is to be carried out.
- Clearances measured need not exceed the maximum values given in the OMM according to the manufacturer's specifications (if provided), or the design value (as per the OMM) plus 2 mm.)
- After dismantling, a visual examination and NDE of hinge pin is to be carried out.
Securing, supporting and locking devices:
- A close visual examination is to be carried out at annual survey.
- Clearances are to be measured, where indicated in the OMM.
- NDE at primary welds and elsewhere, and thickness measurements may be required by the Surveyor after visual examination.
- A close visual examination, supplemented by NDE and thickness measurements, is to be carried out at class renewal survey.
- Cracks and deformations are normally not accepted and are to be dealt with as found necessary.
- When a crack is revealed, a thorough examination, supported by NDE is to be carried out in the surrounding area and for similar items.
- The maximum allowable margin for corrosion is 15% of the original thickness.
- Clearances measured need not exceed the maximum values given in the OMM) according to the manufacturer's specifications (if provided), or the design value (as per the OMM) plus 2 mm.)
Sealing arrangement (packing material/rubber gaskets):
- A close visual examination is to be carried out at annual survey.
- The acceptable permanent compression of seals is not to exceed the maximum value given in the OMM according to the manufacturer's specifications (if provided), or 10% of the packing thickness.
- When cracks due to ageing/hardening are found, pickings are to be renewed (material to be of the same type as the original as far as possible, otherwise it should have equivalent characteristics).
When the examination of Ro-Ro ship’s bow, stern, side and inner doors is carried out by a “service supplier”, it is to be certified according to your procedure. In any case, on-board the ship, the survey of such Ro-Ro ship’s bow, stern, side and inner doors is to be witnessed by the Surveyor.
During the tightness hose test of the sealing arrangement, “weeping” is accepted.
The Surveyor verifies the proper operation of fans located on garages and/or closed spaces (very important due to the existence of petrol vapors).
The electric equipment of safety type is generally examined, particular attention being paid to cable runs and connecting terminals.
Close-up surveys of doors, locking, securing and supporting devices and fittings on Ro-Ro ships.
The following are extracts from IACS IG8 (IACS Unified Requirement Z24 introduced new periodical survey requirements for the bow, inner, side shell and stern doors of Ro-Ro ships. ) giving details of items to check for close-up surveys. This can be used as a guide.
Devices and fittings and associated welding to be subject to close-up survey:
Cylinder securing pins, supporting brackets, back-up brackets (where fitted) and their welded connections hinge pins, supporting brackets, back-up brackets (where fitted) and their welded connections.
Locking hooks, securing pins, supporting brackets, back-up brackets (where fitted) and their welded connections.
Locking pins, supporting brackets, back-up brackets (where fitted) and their welded connections.
Locating and stopper devices and their welded connections.
Fractures are more likely to occur at highly stressed locations, at or adjacent to welds, in way of corroded areas or in way of previously repaired welding.