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PART II. SELECTION OF METHODS OF HULL SHAPING

1) Pyramid method of building up hulls from prefabricated sections.

When the pyramid method is used, building up the hull on the build­ing berth starts with the assembly and welding of the first pyramid, with the sections in the subsequent pyramids butt-assem­bled to it. The entire hull is assembled and welded successively for­ward and astern from the centre of the prefabricated bottom section of the first pyramid, and to the sides and upwards; this ensures that there is free contraction while welding sections, and consequently reduces the total hull deformations. When the first pyramid has been assembled and welded, although it is comparatively short, its section relative to the horizontal axis is already sufficiently rigid.

Pic. 29. Pyramid method. I-V11—pyramid Nos.; the sections for pyramids I, III, V and VII are shaded

This method gives the hull its initial shape as to transverse cross-section (in breadth and depth), but formation in length is somewhat retarded; extension of the working front in the first stage of assembly on the building berth is thus limited.

This method has been given the name "pyramid" since seen from the side the assembled part of the hull represents a pyramid with the terraces formed by the outlines of the individual sections. When the first pyramid has been completely welded, the sections forming the next pyramids are assembled and welded simultaneously, and the fitting-out and installation work is at the same time done in the finished sections of the first pyramid. With the completion of welding on each successive pyramid, fitting-out and installation operations are carried out on an increasingly wide front.

2) The "island" method of building up the hull froт sections.

The work­ing front can be further extended by using the "island" method of assembly; when this method is used, sections are simul­taneously placed in position at two or three zones along the hull (for instance, at the midship, bow, and stern zones). In many cases the sequence of assembly and welding within each island may be the same as with the pyramid method. As soon as welding is finished in each island, fitting-out and installation operations are begun.

Pic. 30. The “island” method. А, В and С—the stern, midship and bow islands; the sections for the initial pyramids in each island arc shown by the criss-cross shading

There may be two, three or more islands, depending on the type, size and design of the ship, also on a number of other factors. The difficulty of building a hull by this method lies in joining the islands together. If the islands are assembled on movable trolleys, they can be joined together by moving the trolleys. If the islands are assem­bled on keelblocks, connecting sections should be installed along the entire perimeter of the hull to join the islands together.

3) The block method of hull construction.

When hulls are constructed by the block method, the building berth assembly cycle is reduced to a minimum, and the welding deformations are also minimum. In the block method the "blocks" (completed parts of the hull

Pic. 31. The block method. I-VI – hull blocks Nos., in the sequence of installing

be­tween sections parallel to the midship plane) are assembled from pre­viously fabricated sections in which installation work has already been done. The finished blocks are despatched lo the building berth, where they are butt-assembled; the installation work in the regions of the butt joints is then completed.

The first block to be placed into position is the base block( in the centre) ; when its position has been checked and it has been fixed on the building berth the neighbouring blocks are joined to it, either one at a time or both at once. If there are a large number of blocks it is sometimes effective to join them in groups of two or three, and then to join two groups (symmetrically) to the base group.

 

Ex. 12. Revise the terms from your active vocabulary.

a) Using the definitions, rearrange the letters to find words used in the text.

 

PGITANL 1. the hull’s shell;

ASTRELEFOC 2. the superstructure erected at the forward end

of the ship;

BEGIRD 3. the superstructure erected about amidships;

WARBULK 4. the strake of shell plating which serves as a

quard against losing deck cargo or men

overboard;

LAKDEHUBS 5. the vertical watertight partitions;

SOFORL 6. the transverse girders stiffening the bottom

plating;

RINGMAF 7. the girderwork stiffening the hull;

RESTGIRNS 8. the longitudinal girders stiffening the side

plating;

ONESKLES 9. the longitudinal girders stiffening the bot-

tom plating;

STOPNREST 10. the rigid structure at the stern.

 

b) Match the words with their definitions.

The forward end of the hull longitudinal bulkheads

The after end of the hull the bottom

The lowermost part of the hull the poop

The topping part of the hull the stern

The wall of the hull side frames

The hull’s shell the forepeak

The superstructure erected at the

after end of the ship side stringers

The transverse girders stiffening the plating

the side plating

The longitudinal girders stiffening

the side plating the deck

The foremost compartment a side

The bulkheads erected fore the bow

and aft

 

Ex. 13. Match the pairs of

a) synonyms.

dispatch original

reduce connect

advantage perform

transverse cross-section send

entire guarantee

contraction minimize

ensure whole

do virtue

initial longitudinal cross-section

join setting

 

b) antonyms.

increase contract

rigid speed up

join reduce

assemble soft

retard divide

extend dissemble

 

Ex. 14. Answer the questions.

 

1) What is the principal problem for all kinds of vessels?

2) What do the stresses (to which the hull of a vessel is subjected) depend on?

3) How many and what main parts does the hull consist of?

4) What is the designation of the bridge?

5) What is the main designation of subdivision members of the ship?

6) What structural members is the hull composed of?

7) What can guarantee the rigidity stability and permanent depth of hull?

8) What does the building up the hull of a ship start with when the “pyramid” method is used?

9) What reduces the total hull deformation in the case of such method?

10) What is the position of the bottom section of the first pyramid to the horizontal axis?

11) Why is extension of the working front in the first stage limited?

12) Can the ”island” method of assembly conducive the further extension of the working front?

13) Are sections simultaneously or successively placed in position in this method?

14) What is the arduous point of building a hull by “island” method?

15) What method of construction permits to reduce the building cycle and welding deformation to a minimum?

16) Are the blocks in the block method assembled from sections with ready installation works or is the installation work done simultaneously when butt- assembled?

17) What makes easier the butt-assembly of the blocks in such method?

Ex. 15. Say, whether the following statements are true or false.

 

1) The prefabricated bottom- section is the beginning of building up the hull with the section in the subsequent pyramid butt-assembled to it.

2) The first pyramid is comparatively short.

3) The hull in the pyramid method is assembled and welded forward and astern from the central (bottom) section, and to the sides and upwards.

4) The disadvantage of the pyramid method is that the initial shape of the hull is developed in breadth and depth, but formation in length is slower.

5) By using the” island” method sections are simultaneously placed in position at the stern, midship and bow zones.

6) The advantage of building a hull by the ”island” method lies in joining the islands together.

7) The block method of hull construction possesses the virtue to minimize the building berth assembly cycle and welding deformation.

8) The blocks are assembled from preliminarily produced sections with completed installation works.

9) The finished blocks are delivered to the building berth where they are butt- assembled; the installation work in places of butt joints is already completed.

10) The principal disadvantage of the block method is that the hull assembly period and shipbuilding cycle is shorter.

 

Ex. 16. Insert the proper words in the text.

 

(Block, stern, hull construction, consisted of, pyramid, bow, building berth, island)

The … method of … was introduced when assembly in large prefabricated sections was first being used; it is now widely for medium and large ships. For instance, the hull of the atomic icebreaker “Lenin”, which … 161 sections weighing up to 80 tons, was constructed on the … by such method (with certain priorities in assembling the stern sections); this meant that installation work in the machinery compartments could be performed at the same time as … and … assembly were been completed.

 

Ex. 17. Using the corresponding pictures from the text report on.

 

a) pyramid method;

b) “island” method;

c) block method.

 

Ex. 18. Read and translate the text.

TEXT 6C

INSTALLATIONS

1) Hull Installation Work.

The term “installation or fitting out work” means the combination of very wide range of different operations included in equipping and fitting out ships, performed after the principle hull structures have been assembled and welded. This work includes. the installation of light partitions, bulkheads and various types of bracing, the painting and insulation of the ship, the installation of the machinery, systems and devices, the equipment of the accommodation and quarters, etc.

The first stage in the work of installation on a ship is installing fittings in the sections. This enables the work to be carried out by parallel method, with the installation work commenced at an early stage in building the ship.

With modern methods of shipbuilding the installation of fittings (rudder, anchor and hoisting equipment, boat handling gear, towing and mooring equipment, handrails, etc.) begins while sections are being fitted up and welded, and the most of the work is performed on the building berth.

Installing of the systems on a ship includes piping, machinery and instruments for moving liquids, steam or air, and controlling their temperature, pressure and so on. For that there are many different technologies (depending on the purpose and location of the systems), so the general sequence of the operations may be established as following.

a) cutting of holes and installation of unions and sleeves;

b) the construction of distance pieces, dismantling, washing, assembly and testing;

c) installing the machinery, instruments and connecting sections of piping from the main line;

d) testing the system as a whole.

The rigging and sailmaking work is done by the rigging shop as follows. making and installing the standing and running rigging, stepping the masts, assembling the anchor fittings and installing the rigging of the boat handing gear. The shop also prepares and assembles the launching devices, and carries out all loading and unloading work.

The sailmaking work consists of producing awnings, tarpaulins and sails (for sailing vessels and life-boats), covers for deck machinery, gear and instruments, flags, life-jacket cases, stair carpets, curtains, etc., and installing all these on board ship. The sailmaking work can also include the preparation of materials for insulating piping.

When all metal parts have been assembled, welded and fitted they are specially treated to protect them against corrosion.

2) Electrical Installation.

Every year the amount of electrical equipment on all types of ship, and the amount of electrical installation work performed during their construction, are increasing. Automatic control and mechanization are developing rapidly, and there are excellent prospects for using electric drives on a large scale and for the complete electrification of machinery and fittings on ships.

Tens of kilometers, and in large ships hundreds of kilometers, of cable are used for connecting up the great number of different types of plant, apparatus, receiving and transmitting devices and instruments at different points on board ship. Immense numbers of adapters, bridges, panels, brackets, packing boxes, cable boxes and pipes, installation frameworks, and different types of fastening device have to be made and installed for the purpose of laying the cables. A great numbers of foundations, frames, brackets, supports, outlets, etc., also have to be made and installed to take the different types of plant, apparatus, receiving and transmitting devices and instruments. Tens of thousands of cable ends have to be separated, marked, fixed, channeled, insulated and earthed in order to create the closed electrical circuits. The total amount of work involved in installing the electrical equipment now amounts to about 10% of all the work in building a ship.

The work of installing all the electrical equipment on ships is carried out by the main shops at the shipyard, and by shops at special undertakings called electrical installation undertakings.

The work of equipping a ship electrically is subdivided into the following periods or stages.

(1) Preparatory work in the shops;

(2) preparatory work on board ship;

(3) external assembly of electrical equipment;

(4) internal assembly of electrical equipment;

(5) protection of wireless receiving stations from interference, and their earthing;

(6) preparation of electrical circuits for handover;

(7) handover tests.

3) Installation of the Auxiliary Machinery.

All shipyards are equipped with powerful cranes for shipbuilding by the large prefabricated section method is a fact in favour of the introduction of integrated methods of installing mechan­ical equipment, for plant of practically any weight can be handled.

According to the method by which it is installed, the auxiliary ma­chinery can be subdivided into four categories.

1) machinery supplied to the ship in the form of individual com­plete assemblies; these have to be aligned on the ship and fixed to the
foundations on wedges (for instance, the steering machinery);

2) machinery including power and working units in the same
housing (for instance, turbine and electric pumps);

3) machinery mounted on one foundation frame by means of which
it is connected to the ship's foundations (diesel generators, diesel
compressors, etc.);

4) machinery with no moving parts (ejector pumps, filters, evapo­rators, desalination plant, condensers, etc.).

Before the auxiliary machinery is installed a check is carried out to ensure that the foundation for the machinery is correctly positioned relative to the base planes and that the dimensions of the supporting surfaces correspond to those shown on the drawings.

The supporting surfaces of the foundations for machinery in the first and second categories are machined using portable (pneumatic) grinders or milling machines, and are filed to a checking template in the same way as the foundations for shaft-line bearings or the main propulsive machinery. Machinery in the first category is aligned by straight edge and feeler gauge, or by indicators, and then mounted on steel wedges or spherical spacing pieces. Machinery in the second category is installed without wedges directly on the machined supporting surface of the foundation, to which it is bolted. If the drawings prescribe that the machinery must be in some particular position relative to the sup­porting surface of its foundation, machinery is mounted on steel spacing pieces of the required thickness.

Machinery of the third and fourth categories is usually mounted on hardwood spacing pieces (oak, ash or teak), and the supporting surfaces of the foundations are not machined, merely dressed. The wooden spacing pieces made in the shop, with an allow­ance for adjustment on the spot. The spacing pieces are fitted to the dressed supporting surface of the foundation and set in position on studs. The upper surfaces of the spacing pieces are planed, and their locations relative to the base reference plane checked by means of water levels and straight edges. The bolt holes are drilled in the foundation using a template taken from the frame or base of the machinery. The holes are marked on the spacing pieces, using the same template, and then drilled by machine. Before being finally placed in position, the spacing pieces are boiled for 2-3 hr in drying oil, or steeped in the engine is installed directly on the shock absorbers.

The shock absorbers are first fixed to the foundation, and the machinery then mounted on them. The bolts are taken up until the base or frame of the machinery makes complete contact with the upper ends of the shock absorber sleeves (or spacing washers), and they are then taken up a further half turn.

Plate shock absorbers are also used; these consist of steel plateswhich a layer of rubber is vulcanized. They are fixed to the

 

Pic. 32. Installation on plate shock absorbers. 1) machinery frame; 2) studs; 3)plate shock absorber; 4) foundation

foundation and machinery with studs which do notreach the layer of rubber. These shock absorbers are not always sufficiently reliable.

4) Installation of Boilers.

The principle of integrating into combinations greatly reduces the labour and time required for installing boilers. To simplify and speed up the installation of boilers a considerable amount of work which was previously performed on the building berth or while prefabricating the blocks is now performed in the boiler shop (or at the boilermaking works); this includes the adjust­ment and installation of fittings and fireboxes; the installation of the piping in the boiler; the installation of base plates and brick linings, insulation of the boilers, etc. The boilers are supplied to the ship fully fitted out for installation, i.e., in the form of integrated combi­nations of equipment. Installation of the main boilers can commence as soon as the basic hull welding is complete and the watertightness tests have been made in the boiler room region.

The foundations for water tube boilers usually consist of separate welded pedestals; these are mounted beneath the forward and after ends of the lower drums. The drums are secured (in the shop) by the screwsto the boiler supports, the lower parts of which are filed and mounted on the base members, the latter welded to the supporting surfaces of the foundations. The supports are bolted on by the bolts. In order that the boiler shall be able to expand when heated, part of the supports has to be made moving.

When water tube boilers are installed, the supporting surfaces of the foundations and the lower surfaces of the boiler supports must be adjusted to one another; this is done by filing the supporting base members. New methods of installing water tube boilers as integrated combinations of equipment have therefore been worked out; with these methods there is no need for machining the supporting surfaces of the boiler foundations. the boiler is installed using an intermediate frame or intermediate parts in the founda­tion. In this case the boiler foundation pedestals are as it were separated into two parts in depth; the upper parts of these pedestals are connected together by box girders into a separate frame called the "intermediate frame". When the intermediate frame has been assembled and welded, the supporting surfaces of its pedestals are machined. The frame is now transported to the assembly stand, and when it has been checked and fixed in position the boiler is fully assembled on it. The boiler supports are finally fixed to the frame pedestals, and spacing pieces are inserted into the gaps at the moving supports in order to fix their position.

At present the principle of integrating into combinations is ap­plied to auxiliary machinery and the apparatus and devices associated with it, which are mounted on the same foundation frame; the principle is also applied to integrating machinery and devices in common housings. Calculations have shown that, in certain cases, the integration of auxiliary machinery on common foundation frames reduces the weight of the founda­tions by 20-25%, reduces the amount of labour required for their fabrication by 75%, and reduces the labour required for their instal­lation on board ship by 60-70%; the amount of piping used is also reduced.

 

Ex. 19. Answer the questions.

 

1. What does the term “installation” mean? 2. What is the first stage of installation work? 3. Where is the most of the installation work performed? 4. What does installing of the systems on a ship include? Enlist the consequence of operations. 5. Why is the sailmaking work still used in modern shipbuilding (exclude sailing vessels)? 6. Can you name the stages of equipping a ship electrically? 7. What categories can the auxiliary ma­chinery be subdivided into? 8. What is the difference in mounting the machinery of these categories? 9. Are the shock absorbers completely reliable? 10. Why is a considerable amount of work for the installation of boilers performed in the boiler shop? 11. What do the foundations for boilers usually consist of? 12. What are the new methods of installing water tube boilers? 13. What are the advantages of the principle of integrating into combinations? 14. Is this principle used in shipbuilding only?

 

Ex. 20. Report on.

a) hull installation work;

b) electrical installations;

c) installation of the auxiliary machinery;

d) installation of boilers;

e) integrated methods of installation.

 

Ex. 21. Abstract the text in short.

Ex. 22. Speak on the topic “Shipbuilding Technology”.

 

 

UNIT VII

SHIPBUILDING IN BELARUS

 

Ex. 1. Read and remember the words.

Carriage, approach, sluice, patronage, access, specificity, scope, negotiation, turnover, forwarder, refinery, molasses, pulp, interaction, abolition, serfage, order, extraction, launch, elaboration, subdivision, item, joinery, pontoon, metalware, overhaul, combustion, spare;

Affect, strive, enhance, benefit, ensure, ransack, manufacture, fulfill;

Navigable, appropriate, acceptable, fair, flexible, internal;

To be underway, to be a stone’s throw away.

 

Ex.2. Insert the right word.

Flexible, turnover, underway, approaching, patronage, joinery, acceptable, manufactured, orders, ensures, spares, access, items;

 

1. The college is under the … of UNESCO and provides the possibility of students exchange. 2. The governmental … makes the largest portion of the plant production. 3. Different … are … by this shop. 4. Such shipment terms are not … for our company! 5. The … to the gate is embarrassed. the … road is blocked by the parked vehicles. 6. The … schedule of shipment is very convenient for construction works. 7. The chief architect … that the project is … . 8. … is produced by the woodworking shop. 9. The … of the port is greater now then ever. 10. The repair must be postponed. we don’t have necessary … .

 

Ex. 3. Change the words of italic type with their synonyms from your active vocabulary

1. Cooperation between these two companies will benefit the project. 2. The shipwrecks of this old ship were robbed long ago. 3. The development of new methods of welding speeded hull construction. 4. There has always been severe competition between cargo carriers, who struggle for new markets. 5. This shipyard produces motor tug boats and various metal structures. 6. A short sea journey will help you to restore your health. 7. The shipment expenses will be sure to increase unless there is no cancel of this toll. 8. This kind of a ship is very seaworthy due to its hull contours. 9. The peculiarity of the new method is its exceptional cheapness. 10. This company branch is in charge for business talks with other companies.

 

Ex. 4. Define in one word.

a) the capital repair;

b) the process of burning;

c) a kind of slavery when peasants work for the feudal;

d) a kind of transport or transportation;

e) to gain profits;

f) to be quite near;

g) a floating bridge;

h) pulling out of smth;

i) water gate;

j) taking place inside smth.

Ex. 5. Translate into Russian.


-river navigable routes

-bordering states

-Water Transport enterprises

-sand-gravel mixture

-building and repair of vessels

-cargo and passenger transportation

-wide range of products

-elaboration and carrying out

-a structural subdivision

-meet the needs in

-floating and portal cranes

-floating means

-shipping rules

-intergovernmental agreements

-great industrial growth

-mechanisms and spares

-the “river-and-sea” type

-the port of registration

-the total turnover of the port

-the second-largest national group

-key position

-the key suppliers of materials

-the basic raw material

-merchant or fishing fleet

-a well-developed transportation infrastructure

-the authorities of the city

-the former naval harbour


 

 

Ex. 6. Read and translate the text.

TEXT 7A

BELARUSIAN WATER TRANSPORT

Belarus has a network of river navigable routes with the length of about 2,000 km that co nnect the country with bordering states. Navigation routes go along the rivers Sozh, Berezina, Dnepr, Pripyat, Neman, West Dvina and the Dnepr-Bug Canal.

The Water Transport enterprises provide

 

Pic. 33. A Tender Motorship

 

design, building and repair of vessels, cargo transportation (including sand and sand-gravel mixture,extraction and transportation) along the rivers of the Republic of Belarus. Besides, the enterprises of the branch produce wide range of products. launches, boats, waterside pontoons, 5-200 liter paint tanks and flexible concrete mats.

Their main tasks are (1) elaboration and carrying out the program of sea and inland transport development; (2) organization, formation, realization of economic and science and technical policy aimed at creation necessary conditions for effective work of sea and inland water transport enterprises, for satisfaction of national economy and population demands in cargo and passenger transportation; Pic. 34. The Motorship “Olga Somova (3) ensuring optimal interaction between different types of transport and increasing transport export service.

The Department of Sea and River Transport of the Ministry of Transport and Communication is a structural subdivision of the Ministry of Transport and Communication.

Enterprises of the river fleet fully meet the needs in transportation of passengers by the water transport of the Republic. Passenger carriage is affected in the towns of Gomel, Brest, Pinsk, Mozyr, Grodno, Mogilev and Loev.

The river fleet ofBelarus today icludes modern

Pic. 35. The Motorship “Grodno”

speedy passenger ships of Polessye type (hydrofoil craft) with the capacity of 53 persons, suburban passenger ships, tug fleet, tugged cargo ships and special ships.

The port facilities are equipped with high-performance floating and portal cranes and mechanized cargo lines designed for fast handling of ships.

Ten river ports of the Republic of Belarus (Mikashevichi, Mogilev, Pinsk, Rechitsa, Vitebsk, Grodno, etc.) are capable of transporting and handling about 22 million tons of cargo. River ports of Gomel, Bobruysk, Brest and Mozyr have railway approach lines and can be used for handling of cargo transported in different directions.

Four waterway enterprises (Gomel, Pinsk, Mozyr, Bobruysk) maintain the required depth of the rivers for navigation of pushed and tugged rolls with the capacity up to 2,000 tons. They have the required bottom-deepening and excavation facilities, modern navigation sluices and hydraulic installations as well as navigation equipment.

The Republic of Belarus has 4 shipbuilding and repair plants (Pinsk, Rechitsa, Gomel, Petrikov) the capacity of which allows building new ships with the dead weight up to 3,000 tons of any class as well as repair of ships in operation.

 

Pic. 36. Belarusian River Port

Design of vessels and floating means are carried out at Republican National Unitary Enterprise “Belsudoproekt” (Gomel).

The control over technical conditions of vessels, certification of items used in shipbuilding is fulfilled by the “Belarusian Inspection of River register” Republican Unitary Enterprise (Pinsk).

The control over fulfilling shipping rules in water ways, ensuring safe navigable conditions as well as holding of State Vessel Register are carried out by Belarusian River Navigation Inspection (Gomel). Transport forwarding companies Republican Unitary Enterprise “Sea Belarusian Steam Navigation and Belarusian Navigable company”, “Belarusian Transport forwarding and Chartering Company” working in the system of the Water Transport provide sea cargo transportation.

Although Belarus is an inland state, it strives to create its own sea trade fleet. Our government sees a lot of advantages in creating its national fleet. One of them is to create jobs for its citizens with maritime professions, another - it will be more convenient for Belarus to transport its production itself.

The year of 2004 saw significant efforts in the field of developing sea shipping in accordance with the instruction of the Belarusian president. The efforts are still underway. The appropriate treaty-legal base was drawn up for the sea shipping activities. In particular, the Inland Water Transport Code and the Commercial Navigation Code were adopted; intergovernmental agreements with Ukraine, Lithuania and Latvia were concluded on the development of inland navigation and transit shipping through ports.

The Belarusian government has stepped up its efforts to create a national merchant fleet. The transport ministry of the Republic of Belarus already has a sea-shipping department. Simultaneously the Belarusian sea lines company is being setting up to carry out sea activities under the government's Program of Inland and Sea Water Transport Development till 2010, which was adopted back in 2003. It is planning that at least two vessels representing our own sea trade fleet of 25 thousand tons displacement will be either leased or bought. They will carry out sea transportations under the Belarusian flag. Now the financial issues are being considered. As for the Navy development, the President stated that Belarus was considering "taking one surface ship and a submarine under Belarusian patronage."

 

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