The mine body of a snip is called a hull. The hull is divided into three mine parts the foremost part is called the bow, the rearmost part is called the stern, the part in between is called midships. In dry cargo vessel the cargo spaces is divided into holds. At the fore end of the hull are the forpeak tanks, and at the after end are afterpeak tanks. They are used for fresh water and fuel. All permanent housing above the mine deck is known as superstructure. On deck there are cargo-handling facilities, such as cranes, winches, derricks. The forward raised part of the deck is called the forecastle and its after raised part is the poop. The angle that a ship is making fore and aft with the water is known as trim. A list or inclination from one side to another, caused by faulty loading is known as hell. The divided circle on the left shows the depth to which the ship may be loaded in summer time. Below this line are on the grid to the right two lines. The one marked W means winter loading, the lower marked WNA means maximum depth if a ships going across NORTH ATLNTIC. T- tropic, F-FRESH waters.
Containerizaition means consolidation of goods of single or mixed commodity into a freight containers may be closed or open and which in conformance to the recommendation of the ISO would be 10,20,30,or 40ft in length by 8ft wide and 9ft or 9ft6inch high in external cross-section. A container is designed to be handled mechanically throughout the transit. Specially designed cellular container ships and efficient port facilities are essential in order to take full advantage of the system. Cellular type full container ships are serviced by shore-based or shipboard gantry cranes. The cellular type full container ship is equipped to carry containers in the holds and on the hatch covers. Within the holds of the vessel there is cellular structure of angle bars forming container guides, into which the containers are stowed, one on top of another. Cellular ships operating between load centres equipped with shore based cranes have the advantage of greater dead-weight capacity as compared to self-sustaining ships fitted with shipboard mounted gantry cranes. In many arias of the world on short interport service fider ships of similar configuration but of reduced capacity are in operation. There are also roll on/roll of container ships on which the containers are mounted on the wheels or trailers and are then rolled on ship and stowed complete with their undercarriage.
Ro-Ro vessels are designed to carry all sorts of rolled vehicles and motor cars by driving them on/of the ship- and unified cargo and lengthy/bulky cargo units. Loading may be effected through the stern bow doors or side ports. Latter inside the vessel motor cars and rolled vehicles are allocated with compliance the cargo plane. The types of access and distribution facilities are numerous each designed to serve a specific purpose such as; stern/bow doors, side ports, the doors being normally hydraulically operated, access ramps, internal ramps, hoistable platforms, lifts, bulkhead doors .We known following types of ramps as internal ramp, fixed ramp movable ramp. On some medium sized ships both bow and stern doors are provided, the ramp arrangement at the bow being similar to that the stern. Such arrangement enables the vehicles to drive straight off the ship without having to be turned or reversed, hence the expression '' drive-through type vessel. Inside the vehicles are distributed throughout the cargo spaces by either internal ramps or hoistable platforms where space is available, fixed or movable ramps are used since permit faster rates of loading than mechanically operated vertical lifts. The advantages of Ro-Ro vessels: independence of port facilities quick door - to door service; faster cargo handling rate and consequently reduced turn-round time; as goods as generally in containers, the risk of damage or pilferage is reduced. The disadvantage of Ro-Ro ships: 1. a considerable amount of cargo volume is occupied by vehicles or trailers; 2. considerable space below the lower deck cannot be used for trailers.
BARGE CARRYING VESSELS.
The only difference between a container and barge is that the latter is much bigger and can float. We known two types barge carrier ship such LASH-lighter aboard ship and SEA BEE barge. The basic difference between the two system is that the LASH ship is a lift-up and lift over type using a 500 tons gantry crane, while the SEA BEE ships float barge on elevator of 2000 t. capacity using rolled system for stowage. The advantages of the barge carrier can anchor and moor clear of quays and thus avoid port congestion, the life of a barge is 2.5 times that of a container and depreciation of a barge is about half that of the equivalent number of containers. The organization of the barge is simpler than that involved with the much larger equivalent number of containers. The disadvantages: distribution is limited, since the barge is restricted to a navigable in land water way suited to the draught of the barge; ice on waterways can restrict barge transport in land waterway transport is relatively slow; this is relation to perishable products.
Tankers are especial designed to carry liquids [mainly oil products] in bulk. Their construction is entirely different from that of dry cargo ships; they are built on a cellular system by which the vessel divided longitudinally and transversely in to compartments. Tankers are equipped with pipes, valves and pumps to transfer cargo from/to the shore and from one tank to another when necessary. The average size is between 20000 and 40 000dwt and speeds vary between 10 and 20knots. Nowadays there are also mammoth tankers of 70 000 - 150 000dwt. Very large crude carriers, /UlCC/ultra large crude carriers of 300 000 to 800 000dwt. and even Megatankers of 1000 000dwt and larger. Only 60 ports in the world have depths of 65 ft. and can accommodate most of the VLCC size vessels. Single boy mooring system permits great flexibility in port location. By using mooring buoys a deep-water port can be created almost anywhere along a coastline. The buoys need not be anchored close to shore; they are placed far out to sea.
MULTI PURPOSE VESSEL
Nowadays universal vessels are gradually being transformed in to multi-purpose vessels. Multi-purpose vessels retaining versatility of universal vessels, that is their capability to carry different bulk and general cargoes are becoming to a certain extend specialized. Thus all multi-purpose vessels are adapted to carry standard containers. Some of them are also adapted to carry rolled vehicles, or heavy bulky cargoes. Operation in Arctic require high ice-breaking capability. They are designed to cope with loads of up to80,20ft containers including refrigerated, trailers ,tracks, explosives and inflammable liquids on voyages to northern autposts.10ft containers carried two layers on the tank top and one layer on the upper deck on return voyage. The cargo handling facilities comprise: deck cranes specifically designed for very cold condition, wide hatches a quarter ramp leading to the after tweendeck and allowing vehicles to move through bulkheads doors, over a tweendeck and a 40ft cargo capacity non-propelling hover craft for discharging cargo on the ice, water or marshy land.
Universal vessels can carry practically any types of cargoes, including refrigerated goods and liquids. Thus liners are intended to carry general cargoes, packaged cargo, containers and also, independence of the route special, liquids and refrigerated cargoes. Their dead weight varies between 2\20000 tns. and the speeds between 10/20kts. Tramp is designed as a rule, to carry bulk cargoes and timber, but can also carry general cargo if necessary. The modern tramp travels are between 12/15kns. Deep tanks may be of two types. First type is designed to carry liquids and dry cargo. Second types for liquids only. Sense late 60s. Universal vessels have been superseded by specialised vessels. But world shipping crises of mind 70s.made shipbuilders and shipowners design new types of universal and specialised combined vessels, as specialised vessels provide to be unprofitable due to their inflexibility. It was than that multi purpose vessel which is further development of universal vessels appeared. Universal vessels have been superseded by specialised vessels.
Bulkers are single-decked ships with no tweendeks in their holds but fitted out with various types of special cargo handling equipment. The cargo is often shot straight in to the holds and discharged by grabs pneumatic suction plants and other bulk handling methods. There are bulk carriers of over 150000 dwt. today but the largest of those in normal use are between 60000 and 70000dwt. Known as Panamax size, while ''handy size bulkers are those in 25000-30000 dwt range.
LIGHTSHIP – LIFEBOAT - PILOT LAUNCH
An usual type of vessel is the lightship. Lightships look like ordinary ships, but they do not have engines, because they are towed into position and then anchored there. They not only have a light, but also a foghorn, a radio beacon and meteorological equipment as well. Most lightships have a crew of approximately twelve.
A very important type of boat is the lifeboat. Lifeboats are of many different types. In the United Kingdom they are manned by volunteers and supported by voluntary donations. Lifeboats must be strong, stable and manoeuvrable and their crew must be well trained.
Pilot launches are motor boats for transporting pilots to and from ships. They must be seaworthy as pilots go out in all weathers. In the United Kingdom, some port authorities employ their own pilots, but many pilots in the other ports are foreign.
The passenger liner can carry a small amount of cargo besides stores and passengers baggage. Accommodation varies with the route. It may be all first-class cabin, or divided into three classes. Some passenger ships may have accommodation for deck passengers. Some liners have propelling machinery aft giving improved passenger accommodation. The main features of passenger liners are the immensely unimportant masts, the enormous number of lifeboats, and the great length of enclosed promenade deck. The giant liners are unmistakable and many people know and recognise them individually.
Tugs usually have the bridge and funnel well forward to leave a clear space aft for the tow rope which is attached to the towing hook or bits at the after and of the superstructure. Two or three steel hoops stretch across the after deck to prevent the rope from fouling the hatches and deck fittings. The ocean going salvage tug is a fast high-powered motor vessel. She can deal with most disasters at sea in the worst of weathers. She is equipped with pumps, fire-fighting apparatus, oxyacetylene plants, and comfortable accommodations for a large crew.