HULL TERMS

Accommodation Ladder is a portable set of steps on a ship’s side for people boarding from small boats or from a pier.

Aft Peak Bulkhead is a term applied to the first main

transverse watertight bulkhead forward of the stern. The aft peak tank is the compartment in the narrow part of the stern aft of this last watertight bulkhead.

Bilge Keel is a piece of plate set perpendicular to a ship’s shell along her bilges for about one third her length to reduce rolling.

Bilge Strake is the strake at the turn of bilge extending outward to a point where the side rises vertically.

Breast Hook is a triangular plate bracket joining port and starboard side structural members at the stem.

Bulkhead Deck is the uppermost continuous deck to which transverse watertight bulkheads and shell are carried.

Bulkhead Structure is the transverse or longitudinal bulkhead plating with stiffeners and girders.

Bulwark is the vertical plating immediately above the upper edge of the ship’s side surrounding the exposed deck(s).

Cargo Area or Cargo Length Area is that part of the ship that contains cargo holds and cargo / slop tanks and adjacent areas including ballast tanks, fuel tanks, cofferdams, void spaces and also including deck areas throughout the entire length and breadth of the part of the ship over the mentioned spaces.
 

Cargo Hold Bulkhead is a boundary bulkhead separating cargo holds.

Cargo Port is a door or port in a ship’s side for the loading or discharge of cargo or stores. Also called side port.

Carlings are supports usually of flat plate, welded in a fore and aft direction between transverse deck beams to prevent distortion of the plating.

Casing is the covering or bulkhead around or about any space for protection.

Ceilings is wood sheathing or planking fitted on various parts of the ship such as tank tops, ship’s sides and bulkheads to protect the ship’s structure from damage and also used to protect the cargo from damage.

Coaming is the vertical boundary structure of a hatch or skylight.

Cofferdams are spaces between two bulkheads or decks primarily designed as a safeguard against leakage of oil from one compartment to another.

Collision Bulkhead is the foremost main transverse watertight bulkhead.

Companion Way is a weathertight entrance leading from a ship's deck to spaces below.

Confined Space is a space identified by one of the following characteristics: limited openings for entry and exit, unfavorable natural ventilation or not designed for continuous worker occupancy.

Cross Deck is the area between cargo hatches.

Cross Ties are used to support the longitudinal bulkheads of oil tankers against hydrostatic and hydrodynamic loads.

Dead Covers are plates of bronze or steel working on a hinge serving to protect the glass port light in heavy weather. Also called dead light.

Deck House is a structure on the freeboard or superstructure deck not extending from side to side of the ship.

Deck Structure is the deck plating with stiffeners, girders and supporting pillars.

Deep Tank is a tank extending from the bottom or inner bottom up to or higher than the lowest deck.

Double Bottom Structure is the shell plating with stiffeners below the top of the inner bottom and other elements below and including the inner bottom plating.

Duct Keel is a keel built of plates in box form extending the length of the cargo hold. It is used to house ballast and other piping leading forward which otherwise would have to run through the cargo holds.

Equipment Number is used by classification societies mainly to determine the size and number of anchors and chain cables for a new ship.

Floor is a bottom transverse member.

Forecastle is a short superstructure situated at the bow.

Forepeak is the area of the ship forward of the collision bulkhead.

Freeboard Deck is normally the uppermost complete deck exposed to weather
and sea, which has permanent means of closing all exposed openings.

Freeing Port is an opening in the bulwarks to allow water shipped on deck to run freely overboard.

Gangway is the raised walkway between superstructure such as between forecastle and bridge or between bridge and poop.

Girder is a collective term for primary supporting structural members.

Gunwale is the upper edge of the ship's sides.

Gusset is a triangular plate, usually fitted to distribute forces at a strength connection between two structural members.

Hatch Coaming is the vertical plating built around the hatchways to prevent water from entering the hold; and to serve as a framework for the hatch covers.

Hatch Covers are wooden or steel covers fitted over a hatchway to prevent the ingress of water into the ship s hold and may also be the supporting structure for deck cargo.

Hatch Ways are openings, generally rectangular, in a ship’s deck affording access into the compartment below. Also called hatches.

Hopper Side Tanks are tanks used for ballast or for stability when carrying certain cargoes in bulk carriers. Also referred to as topside wing ballast tanks and bottom hopper tanks.

Keel is the main structural member or backbone of a ship running longitudinal along centerline of bottom. Usually a flat plate stiffened by a vertical plate on its centerline inside the shell.

Margin Plate is the outboard strake of the inner bottom and when turned down at the bilge the margin plate (or girder) forms the outer boundary of the double bottom.

Midship Section is the cross section through the ship, midway between the forward and after perpendiculars.

Pipe Tunnel is the void space running in the midships fore and aft lines between the inner bottom and shell plating forming a protective space for bilge, ballast and other lines extending from the engine room to the holds.

Poop is the space below an enclosed superstructure at the extreme aft end of a ship.

Poop Deck is the first deck above the shelter deck at aft end of a ship.

Port Light is another term for side light or side scuttle.

Reduced Scantlings are scantlings that are allowed to be reduced because approved corrosion control arrangements have been applied.

Representative Spaces is those which are expected to reflect the condition of other spaces of similar type and service and with similar corrosion prevention systems.

Scupper is any opening for carrying off water from a deck, either directly or through piping.

Scuttle is a small opening in a deck or elsewhere, usually fitted with a cover or lid or a door for access to a compartment.

Shedder Plates are slanted plates fitted in dry cargo holds to prevent undesired pockets of cargo. The term is also commonly applied to slanted plates that are fitted to improve the structural stability of corrugated bulkheads and framing members.

Sheer Strake is the top strake of a ship's side shell plating.

Single Bottom Structure is the shell plating with stiffeners and girders below the upper turn of bilge.

Skylight. A deck opening fitted with or without glass port light and serving as a ventilator for engine room, quarters, etc.

Spaces are separate compartments including holds and tanks.

Stay is a term for bulwarks and hatch coaming brackets.

Stem is the piece of bar or plating at which a ship’s outside plating terminates at her forward end.

Stern Frame is the heavy strength member in single or triple screw ships, combining the rudder post.

Stiffener is a collective term for secondary supporting structural members.

Stool is a structure supporting cargo hold and tank bulkheads.

Strake is a course, or row, of shell, deck, bulkhead, or other plating.

Strength Deck is normally the uppermost continuous deck. After special
consideration of its effectiveness, another deck may be defined as strength deck.

Stringer Plate is the outside strake of deck plating.

Superstructure is a decked structure on the freeboard deck extending for at least 92% of the breadth of the ship.

Suspect Areas are locations showing substantial corrosion and/or which are considered by the Surveyor to be prone to rapid wastage.

Tank Bulkhead is a boundary bulkhead in a tank for liquid cargo, ballast or bunkers.

Topside Wing Ballast tanks are ballast tanks in bulk carriers that normally stretch along the length of the ship’s side and occupy the upper corners of the cargo hold.

Tween Decks is an abbreviation of between decks, placed between the upper deck and the tank top in the cargo holds.

Void is an enclosed empty space in a ship.

Wash Bulkhead is a perforated or partial bulkhead in a tank.

Watertight Bulkhead is a collective term for transverse bulkheads required for subdivision of the hull into watertight compartments.

Wind and Water Strakes are the strakes of a ship's side shell plating between the ballast and deepest load waterline.