Ship knowledge a modern encyclopedia pdf

 
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  1. Ship Knowledge A Modern Encyclopedia
  2. SHIP KNOWLEDGE: A MODERN ENCYCLOPEDIA | Maritime E-Book
  3. Ship Knowledge
  4. SHIP KNOWLEDGE: A MODERN ENCYCLOPEDIA

Ship Knowledge a Modern Encyclopedia - Free ebook download as PDF File . pdf) or read book online for free. about ship and all the details. Format, pdf This is the world famous Ship Knowledge Encyclopedia by Dokmar . pertaining to modern shipbuilding, ship repair, seamanship, modern shipping modes and the offshore industry are dealt with herein. Bulk cargo. Vertical bulkhead or pontoon. Heavy cargo, steel coils. Project cargo. Horizontal decks or hatchcovers s. Ship Knowledge, a modern encyclopedia.

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Ship Knowledge A Modern Encyclopedia Pdf

SHIP KNOWLEDGE: A MODERN ENCYCLOPEDIA Format, pdf subjects related to the modern ship construction and seamanship as well. DownloadShip knowledge a modern encyclopedia pdf. Got the again, I suppose it ll be sent everyday it misses a shipment. Ship knowledge a modern. Ship Knowledge a Modern Encyclopedia (Современная Энциклопедия Судов). Year: Language: english. Author: K. van Dokkum.

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Users can see the below demo video for more information about the phone. Sponson addional buoyancy. IDlIi subtnersiblr at operational draugh:. A semi-submersible drilling unit is used for drilling the exploration and production wells in - 2, m water depth.

Anchored units can operate in max. Dynamically positioned vessels can operate independent of water depth up to around the year drilling was performed in max. An important advantage of the semisubmersible type in comparison with the ship-shaped type drilling vessel is the better motion behaviour of the unit in harsh environments which can give an extended working window.

A dynamically positioned D. A control system continuously determines the required thrust vector based on information from a position reference system, Iike radio or hydro-acoustic beacons or D GPS. These are semi-submersible barges or vessels, equipped with one or two heavy-duty offshore cranes. The maximum hoisting capacity is today 7, tonnes per crane. The vessels are used for transportation and installation of large modules weighing up to 12, tonnes of fixed offshore platforms.

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The base of the platform called jacket is either launched from a barge or lifted onto the sea-bed by the crane vessel prior to installation of the topside modules. After installation of the jacket it is firmly connected to the seabed by steel piles, that are driven down by large hydraulic hammers suspended from the offshore cranes.

Some crane vessels also have pipelaying facilities. The weight of each module is l: The Tension Leg Platform is used for drilling and production purposes. The unit resembles a semi submersible drilling unit and is attached to the sea floor with tensioned steel cables. The buoyancy of the platform applies tension to the cables.

The advantage of the TLP is the economical aspect in comparison with the fixed platforms, specifically for deeper water. In case the production in a particular field goes down, this platform can be reused in other locations. Fixed Production Platforms are prefabricated onshore, transported on barges to their final production locations at sea and subsequently they are installed and completed to facilitate the actual oil I gas production.

The platform can be subdivided into the following main components:. Most platforms stand in water depths varying from approx.

The highest jacket ever built was for a water depth of m. ILl-' O!! Walf'l' dcplh J In the absence of a pipeline from the production facility to the shore terminal a shuttle tanker is needed to take over the oil cargo from the FPSO or FSO on location for transportation to the shore terminal.

Many of these pipelaying barges have a heavyduty crane for installation work. Pipes are supplied to the pipelaying vessel by pipe-supply carriers.

Cranes on the pipelaying vessel unload the carrier and hoist the joints into temporary pipe-storage racks. On the main deck a complete pipe joining and coating factory is provided.

After welding the pipe joints, non-destructive testing NOT is executed prior to transporting the joined pipes horizontally over the firing line to the pipe stinger used in shallow and deep water, max J Ill. The stinger extends out-board over the stern of the pipelaying barge.

This process is controlled by means of pipe tensioners varying in capacity from 40 - tons. For deep water over m water depth installation of subsea pipelines a J-Iay tower is used. The shape of the pipe when lowered onto the seabed resembles a hockey stick hence the designation J-Iay.

During supply operations often DP is used to stay on position Goy-stick controlled. Other functions besides supply are fire fighting and towing of floating units. Suppliers are characterised by a superstructure and deckhouse at the foreship and a long f1at aft deck. They have no heli-deck and no cranes. The offshore platform or vessel uses its own cranes to lift cargo from the PSV deck. An anchor handling tug is used to set and retrieve anchors of moored offshore units and for towing these units.

The AHT often looks similar to a PSV, but has a shorter aft deck and an open stern with a stern roll to be able to pull anchors on the deck. To facilitate the diving operations DSVs have diving belles and decompression chambers for the divers. A moonpool is used to lower divers or subsea tools. Such a subsea tool is the Remotely Operated Vehicle ROV , a selfpropelled underwater robot for inspection or construction and repair work.

Usually the ROV is connected by an umbilical to the support vessel. DSVs are anchor moored or dynamically positioned. When working with divers, very strict requirements to the anchor mooring or DP system apply, as a drift-off of the DSV could bring the divers in danger.

Without diving operations, the DP requirements are less stringent. MSV s can be used for a large variety of tasks like:. The vessel can be ship-. Chase vessels are used to chase ships away from platforms, offshore operations or seismic survey vessels and for supply operations. Of course these tasks can be combined in one ship. Often converted fishing vessels are used for this. Prior to the actual construction of the ship, the shipping company, financer and future owners have already completed a trajectory of negotiations and considerations.

Unlike a car, a cargo ship is not ready for delivery in a wide range of models, but it has to be constructed following the demands of the shipping company. However, it is becoming increasingly popular to classify ships into categories where their designs are then standardised. This makes mass-production possible,.

In spite of the disadvantages, shipyards have introduced good and versatile standardised ships in recent years, Some shipping companies are now ordering whole series of these with sometimes only a few modifications to the design.

The shipping company first makes up an application for specification, This is a list of demands which the ship has to fulfil. It specifies:. Container cargoes in hold and on upperded , strengthened for regular discharge by grabs. The following maritime Rules and Regulations, those coming into effect as of the date of execution of the oontract to be complied with, including rules and regulations known at the day of execution of the contract, coming into force and being applicable to the vessel before actual delivery:.

International convention for the saf8ty of life at sea, and latest amendments International convention on load lines, The shipping company then submits this list of demands to several shipyards.

The shipyards will then let the shipping companies know if they are interested in the assignment. This will depend on:. After the exploratory talks the shipping company sets a time period in which the shipyards can submit an offer without engagement. This means that the shipping company does not have to pay for the offer and that the shipyards do not know which one will get the assignment. Sometimes the shipping company already has a preference for a particular shipyard, and then the offers are used to compare the different prices.

The offer without engagement is the response of the shipyard to the application for specification. The outline specification is a brief technical description and the general arrangement plan is a side view of the ship, which depicts the arrangement of all spaces in the vessel. A list of deviations often accompanies the outline specification.

This shows how the preliminary sketch differs from the application for specification and gives the reasons for the deviations. On the basis of the offers, a shipping company will continue negotiations with 2 or 3 shipyards.

A preliminary sketch is made in the project department of the shipyard. This requires a lot of calculations, especially if the design is entirely new. The demands on computer programming and personnel are quite heavy and if the shipyard is too small to carry out such an amount of calculating work they will co-operate with other shipyards, or subcontract the work.

A computer-programme is used in the following first in the preliminary sketch and later on in the final design:. These calculations also give the stability and the longitudinal strength. The ship's behaviour at sea and its manoeuvrability at different conditions of loading. F Forecaste! B deckfrarnes, postition bullkheads, pos. Niestern Sander bv.

After having studied all the offers, the shipping company will make a definitive choice for a particular design. This leads to a preliminary estimate of construction or preliminary building plan, a document that may be as large as pages.

The preliminary building plan is then sent to two or three shipyards for an offer. This procedure is called a tender, and participating in it is called "to tender". Sometimes the EU demands an "open tender" in which other shipyards, if they are from the EU, can partake. It can sometimes take months for the shipyards to calculate an accurate price from the tender, but they still do not receive any money; there are still no obligations. Finally the order will be granted to one of the shipyards.

In this choice, not just the price is taken into consideration, but also other factors like the reputation of the shipyard working within budget and time and if the shipyard has constructed a vessel for the shipping company before. After this preparation, often lasting a year, the parties involved sign the final building contract.

The building contract establishes all the legal positions and commercial conditions between the shipyard, the shipping company and often also the financier. Now that the building contract has been signed, all the parties have obligations that start with the down payment and end with the delivery on completion and the final payment. Within the contract there will be a provision to allow for adjustment of the price should any changes be made to the original design at some stage during the building contract.

For any alterations or components of which the price is unknown the price will be estimated and included with any other estimates. The payment will be settled at a later date in accordance with the provisions made within the contract. Part of the building contract is the estimate of construction, which.

The shipyard assigns a yard number to the future ship, which is stated on all the drawings and documentation. At this point the clock starts to tick for the time of construction. The building time, as agreed in the contract, comprises the design phase and the building phase. The building time varies between 6 and 24 months. A building group is formed by the shipping company and the shipyard who both appoint people, who are , each person in his or her own field of expertise, responsible for the entire building process until the delivery.

The design department is often called the drawing office, even though nowadays there is not a single drawing table to be found. The ship is worked out in detail in construction drawings or sheer plan or working plan and fr plans. The schemes of all the mechanical, hydraulic, pneumatic, and electrical systems are detailed and the accommodation is drawn in. Certain essential drawings have to be submitted to the classification society where the ship is to be registered.

Ship Knowledge A Modern Encyclopedia

And even though people from the shipping company are in the building group, some drawings still need approval from the management of the shipping company. Furthermore, the whole of the design has to live up to legal demands of the classification bureau, who regularly send their inspectors to the shipyard to assure compliance with initially approved drawings.

There are shipyards that have a small design department. They will contract the design out to an independent marine engineering office, or they will co-operate with other shipyards. The working out of all the details to a complete and approved set of drawings takes tens of thousands or even hundreds of thousands of hours. This is costly; as a rule of thumb up to. In many countries there exists a good co-operation between the various shipyards, and standardisation has led.

This makes it increasingly easy for shipyards to build parts for each other. For certain difficult areas of design, specialist research and engineering firms are approached. These firms will produce work for:. Research on the shape is done both by computer calculations and results of model testing in one of the model tanks. The resistance curves for example are obtained by measuring the required propulsion power at different draughts and speed.

In addition to this, research is done on the inf1uence of swell on the speed, the necessary propulsion power, navigability, the rolling and pitching behaviour and manoeuvrability.

In the case of very large ships, research is done on the extreme forces and moments of inertia that arise in the ship in case of heavy swell. The optimisation of the ship's shape is a very laborious task where measuring and calculating go hand in hand. In the figure above the wave patterns of a ship at a certain velocity before and after optimisation are depicted. The optimisation procedure has reduced the wave resistance because the ship makes fewer waves after optimisation.

The bulb stem has already reduced this resistance because the wave produced by the bulb stem counteracts the bow wave.

However, this is only one effect that. The planning department makes the drawings of the design department ready for production puposes; the right drawings at the right workplace. Furthermore, all the steel parts are given a code. With the aid of a computerprogramme, a draughts man or draughts woman nests the steel plates. This means that the steel plates present at the shipyard s are chosen in such a way that, after cutting into shape, there is a minimal amount of waste.

The computer also controls the cutting torch, a plasma cutter in a water-bath. Because of this the excess heat is drained quickly.

As a result minimal distortions will occur and there is a good control of the exact dimensions of the plates. The cutting machine can also engrave the code number of a part into the steel. Automation of the steel construction has led to more efficiency. Furthermore, the designers will design the sections in such a way that as much welding as possible can be done by welding robots. Building by section enables parts of the double bottom, the foreship and the aft ship to be welded whilst lying upside down in the workplace.

This way of welding produces a uniform quality of the welds within less production time. Because access to the different sections is much more restricted when they are joined together, the sections are completed as far as possible prior to the joining. This means that piping systems, tanks, filters and other small auxiliaries are all placed in the section before the joining of all the sections. The building of a ship used to begin with the placing of the keel followed by the keelplate.

The rest of the construction was then connected to. Nowadays, laying the keel means that the first bottom segment is placed in the assembly hall. Subsequently, the other sections of the ship are then built to or on this. At this stage, the production is well underway.

Modern shipyards do the actual building in large indoor assembly halls where they use pre-painted steel plates. After welding the plates, the joints are immediately painted. Several factors determine where the ship will be finished.

The finishing is either done in the assembly hall or at the fitting out dock.

SHIP KNOWLEDGE: A MODERN ENCYCLOPEDIA | Maritime E-Book

In some cases the deckhouse can not physically fit into the assembly shop. And if the launching of the vessel is going to be an end-launch, the vessel should have the minimal amount of weight on board. The launching is always an exciting moment because at the moment the ship is launched, there is no way of stopping it. In end-launches, the ship acquires so much speed that it takes a lot of effort to stop the vessel in the water.

In sidelaunches, the ship can bounce back against the wharf, especially when the water level is high.

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The ship does not gain much speed, but instead produces very high waves. After the launch, the final touches like masts, hatches, sometimes the engines, funnel, ventilation shafts, cranes etc are added to the ship at the fitting out dock. Finally, the cabins and other spaces are furnished and the inventory is brought on board. When the ships electrical wiring is ready, it is connected to the shore supply to get a voltage.

After this all the engines, generators and auxiliaries are brought on line and the ship can then begin to function independent from the shore. Upon completion of the vessel in the shipyard all the final testing will be conducted at the shipyard with the exception of items which can only be. Final testing at the shipyard is related to electrical systems, engines, generators, pumps, technical equipment, life-saving equipment and a light weight I stability test.

Final testing in open sea is mainly related to final testing of machinery under working conditions, fuel consumption, vessel's speed, rudder tests and anchortests. In principle all these tests will be conducted in the presence of the owner's representativets , classification surveyor s and - if applicable - National Authority representative s. Next is the first, technical, sea trial, which can sometimes take up to 2 days.

This is the first time that the ship leaves the shore and is completely self-reliant. The ship as a whole and all of its parts are extensively tested and all the results are carefully recorded.

The classification society and the Shipping inspectorate are also present to see if all the legal demands are met. In general, these trials are usually successful, but there are always small imperfections which can be amended during or after the trial. How the ship exactly behaves in open sea will become clear when the ship is in use; however, the speed and fuel consumption of the empty ship can be measured during sea trials. More and more shipyards advertise shorter delivery periods, and more and more shipping companies stipulate that.

In order to facilitate this trend, lots of shipyards contract other shipyards to build parts of the ship. It is also common that the hull of the ship is constructed in cheaper countries and that the hull is fitted out and completed locally. But even without these measures, all the semifinished parts must be ready for the next phase of construction to commence. Besides, all the downloadd parts must be ready in time, but not too early because of the costs for storage and the loss of interest.

Keeping the construction process manageable requires that a. Such a management system integrates and controls data from the preparation, design, download, stocks, production, administration and project management. The Shipping Company and Certifying Authorities will finally accept the ship subject to positive results of sea-trial tests and the issue of the relevant certificates. During this short voyage the protocol of consignment is signed, the shipyard's flag will be exchanged by the flag of the shipping company and the financier pays the last installment.

Because there is a month period of guarantee on the ship, the shipping company usually requires a bank guarantee from the shipyard.

This is called upon when the shipyard can. It is normal that in the first month of a ship's life a guarantee engineer from the shipyard is on board. The guarantee conditions are an integral part of the building contract, because, just like any other product, the ship has a period of guarantee. In general, this period is 12 months after the delivery of the vessel.

The shipyard almost always adopts the guarantee conditions and periods of the companies supplying the different ship components. If the ship needs repairing within the period of guarantee, the vessel's location and the urgency of the repair jobs determines who will repair the vessel and where it will be done.

If the ship cannot be repaired at or by the shipyard, for instance, because the ship is in another country, the shipping company is allowed to have the ship be repaired by a third party, but only if the costs of repairing the ship are not more than the price the. This condition protects the shipyards against excessive bills if there is a deal between the shipping company and the repair yard.

Repairs of components and equipment are almost exclusively done by local service-dealers, especially when the parts are of a well-known brake. This is always done in consultation with the shipyard or the supplier. The crew is prohibited to do repairs during the period of guarantee unless the repairs are absolutely necessary. If this is the case, the shipyard has to be contacted for consultation first.

Sometimes suppliers have two periods of guarantee for their product. The first period covers some months after delivery from the factory, the second period covers some months after the product is put into operation.

The reason for this is, that there sometimes is a long period between the delivery to the shipyard and the moment the component is put into operation. There are many forces acting on a ship. How they act is largely determined by the purpose the ship was built for. Forces on a tugboat will be different from the forces acting on a container ship. The types of forces that occur in waves are the same for every ship but the magnitudes and points of action depend on the shape of the ship below the waterline.

These and other forces cause the ship to be det1ected. When the force stops acting, the ship will regain its original shape. Every ship is different and some have more or less of this t1exibility. If, however, the forces exceed a certain limit, the deformation can be permanent. When a ship is in calm water, the total upward force will equal the total weight of the ship.

Locally this equilibrium will not be realised because the ship is not a rectangular homogeneous object. The local. The concepts static and: Static means that the work done on an object is absorbed immediately. Dynamic means that the work done on an object is absorbed gradually,. This, is a static movement because the force exerted en tile swing is absorbed instantaneously,.

As the cargo runner is. This is a static movement because l! The weight of the swing cannot absorb 'this sudden burst of force and gets out of control. This is a dynamic motion. This causes the ship to list vielenrly to the other side. The ship is unable to absorb the sudden change in weight and" as a result, acquires a dynamic motion. The shearing force is the force that wants to shift the athwart-ship plane from one part of the ship to another.

The submerged part of the ship clearly shows the difference in volume between the midships, the fore- and the aft ship; this is the reason for the difference in. In the drawing on the right a part of the aft ship is depicted along with the shearing force near a bulkhead.

The downward force causes a hogging moment of t x 6m. The upward force causes a sagging moment of t x 3m. The bending moment at the bulkhead is: This explains the difference in upward pressure. The black l' YfrJl"S represent the upward pressure and the weigh! The red vectors gil'! Below is an explanation of how bending moments and shearing forces are continuously changing.

As an example a rectangular vessel is used which is divided into three compartments A, B and C. In figures 1, 2 and 3 both outer compartments are filled with cargo. In figures 4 and 5 the inner compartment B is filled with cargo. In figures 2 and 5 the vessel is on a wavetop and in figures 3 and 6 the vessel is in a trough. The upward pressures keep changing because the wave pattern is also changing.

The downward forces however stay the same. The up and downward forces per compartment are depicted as vectors.

The load curve gives the difference of the up- and downward forces per metre at each point on the baseline. The sum of the areas above the baseline and the areas below the baseline should be equal.

The shearing force curve gives a sum of the shearing forces on the right part produced by the left side, going from left to right.

If the direction of the force is changing from upward to downward or vice versa , the shearing force curve will change from rising to falling or vice versa. The shearing force curve has an extreme value at the points where the direction of the force is changing. Converting the load curve to a shear force curve is. The sum of the areas above the baseline has to equal the sum of the areas below the baseline. The bending moment is expressed in tonmetre trn. If the shearing force curve changes from rising to falling or vice versa, the bending moment will bend at the bending point from "hollow" to "round" or vice versa.

When the shearing force curve crosses the baseline, the bending moment line will change from rising to falling or vice versa. The ship will. The situation in figures I and 2 is called a hogging condition and the situation in figures 3, 4, 5 and 6 is called a sagging condition. Around the half height of the vessel there is a "neutral zone".

Here there are hardly any tension or compression stresses. However, especially at the ends of the vessel, heavy horizontal shearing stress can occur. The preceding shows that the biggest stresses occur in the outer fibres: The pictures above show a view that clearly emphasizes the difference in plate thickness between the upper strake of the side bulkhead and the side bulkhead just below it.

In this ship container feeder the upper strake of the side bulkhead is about 2. The place where the plate thickness changes from 22 mm to 9 nun is called the taper. When the ship's officer has entered the weight of all the items on the ship into the loading programme, the computer can calculate the stability, shearing forces and bending moments. The program compares the present situation with the requirements and regulations of the classification bureau and the proper authorities.

The following pages contain a number of examples of loading situations as the computer on board depicts these. The situations have been greatly exaggerated for clarity. Of the total loading programme, only a few shortened pages are shown.

Only the holds in the fore and the aft ship are loaded, resulting in a great hogging moment. The graph shows that the bending moment reaches the limit for seagoing condition.

Therefore, this is a dangerous situation. During un loading in port this bending moment is still allowable. The difference between maximum allowable bending moments at sea level and in the harbour tomes from the additional bending moments due the waves at sea. The cargo is distributed equally over the whole ship, resulting in modest shear forces and bending moments.

Because part of the cargo is placed on the main deck, the initial stability OMO is negative. This means that the centre of gravity 0 is above the metacentre M when the ship has no list. When the ship starts listing M will move upwards due to the widening of the waterline till it reaches G. In case of an increasing difference between G and M the ship will eventually capsize. Only the holds in the midship section are loaded. Because of this the ship experiences a large sagging moment.

In port this is still permissible. See also the table "strength summary" and the graph of bending moments. AP t Seag. OB OB m LCB 1. Ilts -. Iota Harbour x xli m it. B8r1dlng Moment W.. D3 BOI 0.

GM solid 1. Floodangle, Thf Torsion occurs when there is an asymmetry in the mass-distribution over the horizontal plane. For example, if there is a weight of tons on the starboard side of the foreship which is compensated by an equivalent weight on the port side of the aft ship, there will be torsion or torque. I n ad verse weather, especially when the waves come in at an angle, the torsion can increase as a consequence of the asymmetric distribution of the upward pressure exerted by the water on the submerged part of the hull.

Torsion causes a ship to be subject to extra stresses and deformations. This can result in hatches leaking or badly sealing. Especially "open ships", i. A good example are container ships and modern box hold general cargo ships. These occur mostly in the fore-ship during pitching. The constantly changing water pressure increases the stress in the skin and the frames. Panting stress is not a result of hydrostatic pressure, but more a result of hydrodynamic pressure.

To reduce the panting stress effect. En II re [orcpea]c tan]: IrJm nO: Pitching loads occurs in the flat bottom of the foreship as a result of heavy pitching of the ship.

The pitching stresses are reduced by increasing the bottom-plating thickness, by the addition of extra side keelsons and closer spacing of the frames and floors on every frame. These occur when the ship is asymmetrically laden and during rolling of the ship in waves. The effect of the diagonal loads is reduced by the addition of frame brackets, deck beam brackets, cross frames and transverse bulkheads. These result from vertical upward forces where the keel blocks are placed and vertical downward forces between the keel blocks and the side blocks.

These figures, made by computer simulation, show exaggeratedly how a small container ship in heavy waves may be distorted. To prevent the planes plate fields of a ship from distorting under influence of the shearing loads, bending moments and local loads, they have to be stiffened.

Examples of planes are the shell, decks, bulkheads and tank top. Compared to the dimensions of the ship, the plating is not very thick about 10 - 20 mm.

Once the stiffeners are in place, they also contribute to the reinforcement of the plane by reducing the tensions in it and by preventing local buckling. This enables the stiffened planes to be thinner than the planes, which are not strengthened. An example of this are the frames on the inside of the skin, most of which are of the type "Holland Profile" HP. The drawings show the importance of stiffening. If all the frames run parallel in either athwart or fore and aft direction it is possible that the frames can bend perpendicular to the frame direction.

To prevent this, a stiffening is placed perpendicular to the frame direction. Such a stiffening is called a stringer for transverse frames and a webframe for longitudinal frames.

SHIP KNOWLEDGE: A MODERN ENCYCLOPEDIA

Bulkheads are also constructed using this system. In the case of decks, deck beams and deck girders form the stiffening. The WIllie situatior: I Support: I I shell vertical frames I stringers horizontal web frames I bulkheads horizontal stiffening stringersthorizental vertical stiffening web girders decks deck frames I deck girders flat bottom bottom frames fore floors I and aft bottom frames I keelsons trans verse I tank top upper frames fore floors I and.

Frames 2. Ice frames 3. Web frames 4. Deck frames 5. Deck beams 6. Centre keelson 7. This is why ships with a length of more than 70 metres are usually constructed according to a longitudinal stiffening system. This means that the frames and the deck beams run in the fore and aft direction. Ship shorter than 70 metres for example fishing boats and tugboats are. Lloyd's Register does not require a calculation for longitudinal strength if the ship is shorter than 65m.

On the next pages we see two different kinds of ships. First a doublehull tanker built with the longitudinal framing system, secondly a tug boat built with transverse frames.

Plating Stiffenings on the plating Plate-stiffeners Holds 1. Shell 8. Side longitudinals 13 Tie beam or cross-tie Wing ballast tank 2. Longitudinal bulkhead 9. Published on Apr 10, SlideShare Explore Search You. Submit Search. Successfully reported this slideshow. We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime. Ship knowledge a modern encyclopedia. Upcoming SlideShare.

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