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TOPIC: FORE END ARRANGEMENT

This is normally the structure, which is the forward quarter (25 %) of the ship's

length. This part of the ship is su!ected to additional forces during slamming andpounding in hea"y weather. #or higher speed "essels such as container ships the

forward hull elow the waterline is su!ect to additional hydrodynamic forces.

The purpose of fitting a fore$castle superstructure at fore end is to protect foredec

fittings against green sea loads and minimi&e the impact of such loads on fore

hatch co"ers. inimum ow height and reser"e uoyancy would require

additional reser"e uoyancy forward consistent with the pro"ision of some sheer

andor a forecastle.

hipuilding rules require additional stiffening in the forward part of the ship in form

of reduced frame spacing, fitting of panting eams, panting stringers etc in addition tothe collision ulhead, floors, frames, eams and other normal internal structures.

Fore Peak Tank

*t is a watertight tannormally used for allast purposes so that the ship can e

pro"ided with the proper trim especially on the allast !ourney.

+ watertight collision ulhead is fitted in the fore pea tan so that in the e"ent of a

collision, damage to the cargo located aft of the collision ulhead will e minimi&ed.

The chain locer for storing the anchor chain is normally located inside the fore pea

tan.

Fore Peak Tank Construction

The following structures are found in the fore pea tan

(-) Stem plate or stem bar or a comination of oth in the forward most structure,

which forms the profile of the ow. The stem plate is normally made of steel

plate and is stiffened y a centerline girder or stiffener. The stem runs from the

highest point at the forecastle to the eel of the ship.

(2) reast !ooks are fitted at inter"als to stiffen the stem plate and to connect the

stem plate to the panting stringers or side stringers.

() Pantin" strin"ers or side strin"ers are fitted at regular inter"als on the ship side

to reduce panting, the inward and outward deformation of side plating (the

/hungry horse0 effect) caused y the changes in water pressure.

(1) anting beams are normally spaced at e"ery other frame space to asor the

trans"erse fluctuating forces induced during slamming and pounding of the ship.

3hannel ars are normally used as panting eams. anting eams are also

sometimes supported y pillars.

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(5) Per#orate$ bulk!ea$ (also nown as swash ulhead or wash ulhead) refers to

the centreline ulhead which is not watertight. *ts main function is to reduce free

surface effect or heeling moments of water in tans, which are not fully filled.

(6) Per#orate$ flat (also called perforated dec) is a hori&ontal dec which is nonwatertight. *t acts as a ind of a full panting stringer to asor the trans"erse

forces. The dec is supported y panting eams and longitudinal girders lie a

usual dec. The perforations on the dec are to facilitate the flow of liquid in the

fore pea tan and also for man entry.

(7) Soli$ #loors are fitted at e"ery frame spacing to reinforce the ship's ottom. +

centreline girder is normally fitted to pro"ide for rigidity of the structure with the

trans"erse floors.

(8) Collision bulk!ea$ is mandatory and to e fitted at aft of the fore pea tan at a

distance of 5 to 7.5% length of the ship from forward perpendicular.

(9) Deck!ea$ is the uppermost dec of the fore pea tan which is watertight. :ntry

to the fore pea tan is through man holes which are ept watertight y co"ers

when ship is under way.

ulbous o%

*f a sphere is immersed !ust elow the surface, and pulled through the water, a wa"e is

created !ust ehind the sphere. The wa"e from the sphere interferes with the normal

ow wa"e and results in a smaller ow wa"e. Thus the force required to produce the

ow wa"e is reduced. ;owe"er, the wetted surface area of the ship is increased,

causing a slight increase in the frictional resistance. #itting a ulous ow reduces thewa"e maing resistance, which forms a large proportion of the total resistance. +

ulous ow also increases the uoyancy forward and hence reduces the pitching of

the ship to some small degree.

The construction of the ulous ow consists of steel plates, internally supported y a

center$line we and hori&ontal plates (aout - m apart).

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#ore :nd tructure

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$$$The :nd of 3hapter$$$

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fore end

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