Ship construction Ship dimensions

SHIP CONSTRUCTIONSHIP DIMENSIONS

Mohd. Hanif Dewan, Chief Engineer and Maritime Lecturer & Trainer, Bangladesh.

Definitions and Ship’S DimenSionS Hull: The structural body of a ship including shell plating, framing, decks and bulkheads. Afterbody : That portion of a ship’s hull abaft midships. Forebody: That portion of a ship’s hull forward midships. Bow : The forward of the ship Stern : The after end of the ship 8/23/2014

Mohd. Hanif Dewan, Chief Engineer and Maritime Lecturer & Trainer, Bangladesh.

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Length Overall

STARBOARD Beam

PORT

bow

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midships

Mohd. Hanif Dewan, Chief Engineer and Maritime Lecturer & Trainer, Bangladesh.

bridge

stern

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starboard beam starboard bow

starboard quarter

Dead Stern

Dead ahead

Port bow

port quarter

Port beam

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Mohd. Hanif Dewan, Chief Engineer and Maritime Lecturer & Trainer, Bangladesh.

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Port : The left side of the ship when looking forward Starboard : The right side of the ship when looking forward

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Mohd. Hanif Dewan, Chief Engineer and Maritime Lecturer & Trainer, Bangladesh.

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SHIP DIMENSIONS Sheer aft

Sheer fwd freeboard Summer load line Amidships

Length between perpendicular (LBP) Length on waterline (LWL) Length overall (LOA)

Aft perpendicular

Fwd perpendicular

Tumble home Camber

Depth Moulded beam Draft Base line Rise of floor

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Half siding of keel

Mohd. Hanif Dewan, Chief Engineer and Maritime Lecturer & Trainer, Bangladesh.

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• After Perpendicular (A.P.): A perpendicular drawn to the waterline at the point where the aft side of the rudder post meets the summer load line. Where no rudder post is fitted it is taken as the centre line of the rudder stock. • Forward Perpendicular (F.P.): A perpendicular drawn to the waterline at the point where the foreside of the stem meets the summer load line. • Length Between Perpendicular (L.P.P. / L.B.P.): The length between the forward and the aft perpendiculars measured along the summer load line. 8/23/2014

Mohd. Hanif Dewan, Chief Engineer and Maritime Lecturer & Trainer, Bangladesh.

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• Amidships: A point midway between the after and forward perpendiculars • Length Overall (L.O.A.): Length of the vessel taken over all extremities. • Base line: A horizontal line drawn at the top of the keel plate. All vertical moulded dimensions are measured relative to this line • Moulded beam: Measured at the midship section is the maximum moulded breadth of the ship 8/23/2014

Mohd. Hanif Dewan, Chief Engineer and Maritime Lecturer & Trainer, Bangladesh.

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• Moulded Draft/ Draught: The distance from the bottom of the keel to the waterline. The load draft is the maximum draft to which a vessel may be loaded • Moulded Depth: Measured from the base line to the heel of the upper deck beam at the ship’s side a idships. • Sheer: Curvature of decks in the longitudinal direction. Measured as the height of deck at side at any point above the height of deck at side amidships 8/23/2014

Mohd. Hanif Dewan, Chief Engineer and Maritime Lecturer & Trainer, Bangladesh.

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• Camber / Round of Beam: Curvature of decks in the transverse direction. Measured as the height of deck above the height of deck at side • Rise of floor / Deadrise: The rise of the bottom shell plating line above the base line. This rise is measured at the line of moulded beam • Half sliding of keel: The horizontal flat portion of the bottom shell measured to port or sta oa d of the ship’s lo gitudi al e t e line. This is useful dimension to know when dry-docking. 8/23/2014

Mohd. Hanif Dewan, Chief Engineer and Maritime Lecturer & Trainer, Bangladesh.

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• Tumble home: The inward curvature of the side shell above the summer load line. • Freeboard: the vertical distance measured from the waterline to the top of the deck plating at the side of the deck amidships. Normally exposed to weather and sea. • Flare: The outward curvature of the side shell above the waterline. It promotes dryness and is therefore associated with the fore end of ship 8/23/2014

Mohd. Hanif Dewan, Chief Engineer and Maritime Lecturer & Trainer, Bangladesh.

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Extreme Beam: The maximum beam taken over all extremities. Extreme Draft: Taken from the lowest point of keel to the summer load line. Draft marks represent extreme drafts. Extreme Depth: Depth of essel at ship’s side f o of keel.

uppe de k to lo est poi t

Half Breadth: Si e a ship’s hull is sy et i al a out the lo gitudi al centre line, often only the half beam or half breadth at any section is given. 8/23/2014

Mohd. Hanif Dewan, Chief Engineer and Maritime Lecturer & Trainer, Bangladesh.

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SCANTLING The dimensions of the structural items of a ship, e.g. frames, girders, plating , etc. INTERCOSTAL Composed of separate parts, noncontinuous

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Mohd. Hanif Dewan, Chief Engineer and Maritime Lecturer & Trainer, Bangladesh.

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CENTER OF FLOATATION It is the center of the waterplane area and is the axis about which a ship changes trim. CENTER OF BUOYANCY It is the center of the underwater volume of the ship where the force of buoyancy acts.

CENTER OF GRAVITY It is the point at which the whole weight of the object may be regarded as acting. If the object is suspended from this point, it will remain balanced and not tilt. 8/23/2014

Mohd. Hanif Dewan, Chief Engineer and Maritime Lecturer & Trainer, Bangladesh.

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TONNAGE MEASUREMENT • This is often referred to when the size of the vessel is discussed, and the gross to age is uoted f o Lloyd’s egiste . • Tonnage is a measure of the enclosed internal volume of the vessel, 100 cubic feet representing one ton • Its normally divided into categories as follow:8/23/2014

Mohd. Hanif Dewan, Chief Engineer and Maritime Lecturer & Trainer, Bangladesh.

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1. Displacement Tonnage • A ship’s displa e e t is the su of the ship’s a tual eight light eight a d it’s o te ts (deadweight). • The metric unit of measurement is 1 tonne (= 1000 Kg). • The displacement represents the amount of water displaced by the ship expressed in tonnes. • The weight of water displaced therefore equals the weight of the ship 8/23/2014

Mohd. Hanif Dewan, Chief Engineer and Maritime Lecturer & Trainer, Bangladesh.

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TONNE PER CENTIMETRE (TPC) It is the mass required to increase the mean draught by 1 centimetre. LOAD DISPLACEMENT The weight of the ship and its content, measured in tonne. The value will vary according to the ship’s draught. DEADWEIGHT SCALE It is a scale diagram indicating the deadweight of the ship at various draughts. FORM COEFFICIENT It is devised to show the relationship between the form of the ship and the dimension of the ship.

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Mohd. Hanif Dewan, Chief Engineer and Maritime Lecturer & Trainer, Bangladesh.

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2. Lightweight Tonnage (LWT) • The lightweight is the weight of the ship as built (hull, machinery) including boiler water, lubricating oil and the cooling water system. • Lightweight like displacement is expressed in units of tones. • It assumes importance in a commercial sense only when considering the value of the vessel which is to be broken up for scrape. 8/23/2014

Mohd. Hanif Dewan, Chief Engineer and Maritime Lecturer & Trainer, Bangladesh.

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3. Deadweight tonnage (DWT) • Deadweight is the weight of the cargo which a ship carries plus weights of fuel, stores, water ballast, fresh water, crew and passengers and baggage. • It is the difference between the loaded ship displacement and the lightweight.

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Mohd. Hanif Dewan, Chief Engineer and Maritime Lecturer & Trainer, Bangladesh.

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4. Gross Tonnage (GT) • Measurement of total internal volume of a vessel and includes all under deck tonnage and all enclosed spaces above tonnage deck. • 100 cubic feet of space being considered as 1 ton

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Mohd. Hanif Dewan, Chief Engineer and Maritime Lecturer & Trainer, Bangladesh.

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5. Nett Tonnage (NT) • Ship measurement derived from gross tonnage by deducting spaces allowed for crew and propelling power. • 100 cubic feet of space being reckoned as 1 ton

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Mohd. Hanif Dewan, Chief Engineer and Maritime Lecturer & Trainer, Bangladesh.

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Ship side markings • LOAD LINE The marking on the ship side that relate to the loading condition of the ship termed as the load line mark. • Load line mark – consists of a ring 300 mm in outside diameter and 25 mm thick which is – intersected by a horizontal line 450 mm in length and 25 mm thick, the upper edge of which passes through the centre of the ring. The centre of the ring is placed amidships and at a distance equal to the assigned summer freeboard measured vertically below the upper edge of the deck line. Mohd. Hanif Dewan, Chief Engineer and 8/23/2014

Maritime Lecturer & Trainer, Bangladesh.

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Mohd. Hanif Dewan, Chief Engineer and Maritime Lecturer & Trainer, Bangladesh.

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Mohd. Hanif Dewan, Chief Engineer and Maritime Lecturer & Trainer, Bangladesh.

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Sailing ship

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Mohd. Hanif Dewan, Chief Engineer and Maritime Lecturer & Trainer, Bangladesh.

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ANY QUESTION?

THANK YOU! 8/23/2014

Mohd. Hanif Dewan, Chief Engineer and Maritime Lecturer & Trainer, Bangladesh.

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