Ship Damage Control

• Damage control is a procedure to reduce the harmful effects of impairment to a ship.
• The objectives of damage control are to:
• Preserve the watertight integrity of the ship
• Make rapid repairs to damaged gear and structures
• Maintain the stability and maneuverability of the ship

Damage Control Systems

• There are several damage control systems including:
• Drainage and flooding systems
• Fire main and sprinkling systems
• Fuel and fresh water systems

Drainage and Flooding

• Drainage is used for:
• Removing large quantities of water from compartments
• Removing water from the hull under normal operating conditions
• Flooding is used for:
• Flooding compartments to balance the ship
• There are three principal types of drainage systems:
• Main drainage system: High capacity, uses piping and pumps to move large quantities of water quickly
• Secondary drainage system: Drains smaller compartments forward and aft of the main drainage system
• Main condenser circulatory pumps: Can be used for emergency drainage of the engine room

Fire Main System

• The fire main system is made up of piping, pumps, plugs, valves, and controls.
• It is designed to supply plenty of water for firefighting.

Fuel and Fresh Water System

• The fuel and fresh water system consists of tanks, filling lines, and feed lines.
• It is important in damage control because the list and trim of the ship can be partially controlled by shifting the contents of the tanks.

Watertight Integrity

• Damage control depends on the proper utilization of watertight integrity features.
• Ships are divided into compartments for the purpose of:
• Controlling flooding
• Segregating activities of personnel
• Providing underwater protection via tanks and voids

Bulkheads

• A bulkhead is a transverse or longitudinal partition that separates compartments.
• A watertight bulkhead:
• Is made of heavier metal than an ordinary bulkhead
• Is mostly unpierced except for watertight doors, piping, or wiring
• A collision bulkhead:
• Is designed to protect from flooding throughout the ship
• The bow collision bulkhead is the first transverse bulkhead aft of the stern
• The last transverse bulkhead aft is the collision bulkhead that protects the after part of the ship

Doors and Hatches

• Doors and Hatches are enclosures for bulkhead openings.
• They are constructed to be as structurally strong as the bulkhead where they are installed.
• Watertight doors:
• Are used in watertight bulkheads on the second deck and below
• Are designed to resist 1 ½ times as much pressure as the bulkhead they service
• Have 6 to 12 dogs for securing
• Non-watertight doors:
• Are used on non-watertight bulkheads
• Usually have fewer dogs than watertight doors, made of dogs which require individual protection
• Hatches:
• Horizontal doors used for access through decks

Closure Fittings and Gaskets

• Gaskets:
• Are made of rubber and installed on doors and hatches
• Close against knife edges to form a watertight and airtight seal
• Must be kept free of dirt and grease
• Knife edges:
• Built out from decks and bulkheads
• Gaskets on watertight doors and hatches close on knife edges
• Dogs and Pins
• Pins are used to connect dogs to the deck or bulkheads
• Dogs are used to make closures