.watertight door

.wtr tight door .wtd

Watertight as defined in SOLAS is: capable of preventing the passage of water in any direction under the head of water – that is likely to occur in intact and damaged conditions.

it can withstand water pressure from both sides. They are designed to withstand continuous submersion and are therefore located below waterline like shaft tunnels, ballast tanks, bow thruster compartments etc.

Depending upon the construction

Hinged type: A door having a pivoting motion about one vertical or horizontal edge.

Sliding type: A door having a horizontal or vertical motion generally parallel to the plane of the door, powered by hydraulic cylinders or electric motors.

Solas Regulations Regarding Closure of Watertight Doors

(As per Solas regulation, SOLAS chapter II-1, watertight doors from regulation 14 to regulation 25)

1. All the power operated doors must be capable of closing simultaneously from bridge and Ship Control Center (SCC). Door Closing time not more than 60 seconds when the ship is in an upright condition.

2. The door shall have an approximate uniform rate of closure under power. The closure time, from the time the door begins to close to the time it closes completely, shall be in no case less than 20 seconds or more than 40 seconds with the ship in an upright condition.

3. In case of hand operation of the door, during a power failure, the door must be closed within 90 seconds.

4. Power-operated sliding doors shall be capable of closing with the ship listed to 15 degrees either side.

5. Power-operated sliding doors should be provided with a local audible alarm distinct from any other alarm in that area. The alarm shall sound for at least 5 seconds whenever the door is closed remotely. The alarm shall  sound not more than 10 seconds before the door begins to move. The sound should be audible until the door is completely closed.

6. Controls for opening and closing the door should be provided on either side of the door. The door control shall also be provided on the central operating console at the bridge. The control handles are located at least 1.6m above the floor on passenger ships.

7. Visual indicator for the door “closed or open” provided in navigation bridge. A red light indicates a door is fully open and a green light indicates that the door is fully closed.

8. The direction of movement should be clearly indicated and displayed at all operating positions.

9. There is also a secondary control station above the bulkhead deck, so that the powered watertight doors can be closed when local  control cannot be reached due to fire or flooding.

Different Types of Watertight Doors on Ships

TYPE A: This type of doors may be left open and are to be closed only during an emergency.

TYPE B: This type of watertight doors should be closed and are made to remain open only when personnel are working in the adjacent compartment.

TYPE C: This type of watertight doors is to be kept closed all the time. It may be opened only for sufficient time when personnel are passing through the door compartment.

TYPE D: This type of watertight doors is not SOLAS compliant. These doors shall be closed before the voyage commences and shall be kept closed during navigation. These doors cannot be upgraded to another category.

Maintenance of watertight door

It is also important to stick to the manufacturer’s maintenance guide. Before any maintenance work is carried out, warning notices should be posted.

• The door should be free from dirt and loose particles. Door frame and gasket should be cleaned routinely. Gaskets can be lubricated with silicone oil.
• Wheels and bearings must be checked for excessive wear and damage. The rails should be cleaned and checked for any damages.
• The hydraulic system should be periodically checked for any leakages. Special attention to be paid to the condition of pumps, hydraulic cylinders, hydraulic hand pump, pipe connections.  The oil level must be checked and refilled if necessary. The hydraulic oil and filter must be replaced as per the ship’s PMS.
• Great care should be taken when the doors or areas near the doors are painted. Avoid painting the rubber gaskets and the piston rods on the cylinders.

• Lubrication of the mechanical parts should be carried out  Mechanical parts include the cleat bolts, the locking device, wheels, lifting cam and arm of the door
• Structural damage in the frame or steel structure should be inspected during routine inspections – watch out for any cracks, indentations or corrosion.
• All doors shall have the clear operating instructions posted on either side of the door. The assigned category whether A, B, C or D as well as their meaning should be marked on both sides of the door. The instructions should be in the ship’s working language and in a legible condition.

Failure in the proper maintenance and operation of watertight doors can draw the attention of Port State Control inspectors and can be a cause of vessel detention.

Missing portions of gaskets, leakage of hydraulic oil, faulty alarms, lack of door closed indication in remote operating positions are some deficiencies that have been observed during the inspection.

watertight door tightness check

Chalk method:

• Watertight hatch cover and watertight doors’ tightness can be check by chalk method or hose methods.
• Apply chalk to watertight flat sealing continuously.
• Close the door tightly, then open
• Check the watertight door sealing.
• If the chalk mark is found continuously around the watertight sealing, then it has water tightness.

Hose method:

• Close the watertight door or watertight hatch cover tightly.
• Hosing with water jet with a pressure of 2 bar and directed to the sealing edges away from 1.5 m.
• There must be no water leak through the other side.
• That door or hatch are good in order for watertight.