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Fig. 2.2. Uk Oil Consumption and Production

IV. 1) Look at the pie charts in Fig. 2.3 and Fig. 2.4. What do they show?

2)Read the description of the pie charts and answer the questions:

1.What does respectively mean?

2.The word while is used to contrast two pieces of information. Find two other words which have the same function.

Fig. 2.3. Passenger Transportation in Croatia

Fig. 2.4. Cargo Transportation in Croatia

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The pie charts compare the use of different modes of passenger and cargo transportation in Croatia. It can be seen that more than half of all passengers choose to travel by road, accounting for 58%, while just under half of all cargo is carried by road. About a third of all passengers use rail transport but only 11% of Croatia’s cargo goes by rail. Croatia has a long coastline and just under a third of Croatia’s cargo is transported by sea. However, only 9% of passengers use this form of transport. This is probably because sea transport is cheaper for cargo but too slow for passengers. Pipeline and inland water transportation account for 8% and 1% of cargo transportation respectively.

V. CD Tape-6. 1) Listen to Lee Avatar giving a presentation describing the use of plastics and tick the expressions you hear him use:

Useful language for referring to visual aids: I’d like to show you a pie chart which represents…

This pie chart represents…

If we take a look we can see… You will notice…

I’d like to draw your attention to… As you can see …

Take a look at… You will see… You can see that…

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0.__

1.__

Words and word combinations to the part VI

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SUPPLEMENTARY READING

Read the texts and do the tasks given after them:

Part I. Materials Science And Technology

Materials under Stress

Some materials are equally strong in compression, tension and shear. However, many materials show some differences; for instance, cured concrete has a maximum strength of 2. 000 psi in compression, but only 400 psi in tension. Carbon steel has a maximum strength of 56. 000 psi in tension and compression, but maximum shear strength of only 42. 000 psi; when dealing with maximum strength, you should always state the type of loading.

A material that is stressed repeatedly usually fails at point below its maximum strength intension, compression, or shear. For instance, a thin steel rod can be broken by hand bending it back and worth several times in the same place; however, if the same force is applied in a steady motion (not bent back and forth), the rod cannot be broken. The tendency of a material to fail after repeated bending at the same point is known as fatigue.

On nonferrous metals, strength is the property that enables a metal to resist deformation under a load. The ultimate strength is the maximum strain a material can withstand. Tensile strength is measurement of the resistance to being pulled apart when placed in tension load.

1.Are all materials equally strong in compression, tension and shear?

2.What is fatigue?

3.What is the property that enables a nonferrous metal to resist deformation under a load?

Monitoring Deflection and Load in Forging Press Tie-Rods

In the forging industry there are two basic types of forging presses and another type of forging machine known as a solid cast steel structure that has four load-bearing members (tierods or columns) located at the four corners of the die bed. The second type of press is typically comprised of three cast steel components held together with steel tie-rods. An upsetter is another forging machine that is held together with the two forging presses described above. The traditional methods of measuring deflection and strain (and subsequently load) included dial indicators and foil strain links. A rod at the top of the press column would extend downward to a dial indicator which was attached to the press column. As the press would undergo a forging cycle, the deflection of the column was read from the dial indicator needle.

Another method includes attaching large low output strain links to the columns of a forging press. During a forging cycle, the deflection is recorded from the strain links on each of the columns. The problem with the foil strain kinks is frequent drifting out of calibration. The links are also expensive to replace or recalibrate.

The Smart Gauge strain monitoring system manufactured by Angstrom Corporation, is an accurate, dependable alternative for measuring forging press column deflection. The system uses high output LVDT (linear variable differential transformer) technology as the heart of its strain monitoring system.

1.What types of forging presses does the text describe?

2.What did the traditional methods of measuring deflection and strain include?

3.Is the Smart Gauge strain monitoring system an alternative for measuring forging press column deflection?

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Horizontal Milling and Boring Machine with Movable Column

The machines are intended for draft and fair machining different high-gravity and largesized case workpieces. On machines it is possible to drill, bore, mill holes of large diameters, cut metric and whitworth thread with single point tools, taps and hobs, face, mill different curvilinear surfaces, including three-dimensional, of workpieces manufactured from cast iron, steel, non-ferrous metals and their alloys.

The machines are equipped with AC high moment motors by Siemens. As to design machines are executed with a movable column moving on the bed’s quideways, along the steelsheet floor, and with a vertically moving spindle head. The spindle head is a sliding ram, in which sliding and unsliding spindles are built on. The cutting tool is fixed in the sliding spindle’s cone, at the sliding and unsliding spindles’ faces. The machine is furnished with a lift with sliding platform on which the workpiece is arranged.

To expand technological abilities of the machines, to use them by a special order and at the additional expense auxiliary units are delivered. Due to applying of different attachable tools and a rotary table, workpieces can be machined from five sides without a reinstallation.

1.What are the machines used for?

2.What operations can be done on the machines?

3.Name the parts of the machine.

Part II. Metals

Metals Application

Some metals and metal alloys possess high structural strength per unit mass, making them useful materials for carrying large loads or resisting impact damage. Metal alloys can be engineered to have high resistance to shear, torque and deformation. However the same metal can also be vulnerable to fatigue damage through repeated use or from sudden stress failure when a load capacity is exceeded. The strength and resilience of metals has led to their frequent use in high-rise building and bridge construction, as well as most vehicles, many appliances, tools, pipes, non-illuminated signs and railroad tracks.

The two most commonly used structural metals, iron and aluminium, are also the most abundant metals in the Earth's crust.

Metals are good conductors, making them valuable in electrical appliances and for carrying an electric current over a distance with little energy lost. Electrical power grids rely on metal cables to distribute electricity. Home electrical systems, for the most part, are wired with copper wire for its good conducting properties.

The thermal conductivity of metal is useful for containers to heat materials over a flame. Metal is also used for heat sinks to protect sensitive equipment from overheating.

The high reflectivity of some metals is important in the construction of mirrors, including precision astronomical instruments. This last property can also make metallic jewelry aesthetically appealing.

Some metals have specialized uses; radioactive metals such as uranium and plutonium are used in nuclear power plants to produce energy via nuclear fission. Mercury is a liquid at room temperature and is used in switches to complete a circuit when it flows over the switch contacts. Shape memory alloy is used for applications such as pipes, fasteners and vascular stents.

1.How are iron and aluminium characterized?

2.What is the application of copper?

3.What metal characteristic is important when constructing mirrors?

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Gold

Gold articles are found extensively in antiquity mainly as jewelry e. g. Bracelets, rings etc. Early gold artifacts are rarely pure and most contain significant silver contents. This led to the ancients naming another metal — electrum, which was an alloy of gold and silver, pale yellow and similar in color to amber. Therefore, early gold varied from pure through electrum to white gold. The symbol for gold is Au from the Latin aurum meaning shining dawn.

Stone Age man learned to fashion gold into jewelry and ornaments, learning that it could be formed into sheets and wires easily. However, its malleability, which allows it to be formed into very thin sheet (0. 000005 inches), ensures that it has no utilitarian value and early uses were only decorative. As gold is a noble metal, being virtually noncorrosive and tarnish free, it served this purpose admirably.

Gold is widely dispersed through the earth's crust and is found in two types of deposits: lode deposits, which are found in solid rock and are mined using conventional mining techniques, and placer deposits which are gravelly deposits found in stream beds and are the products of eroding lode deposits. Since gold is found uncombined in nature, early goldsmiths would collect small nuggets of gold from stream beds etc. , and then weld them together by hammering.

1.What does gold mean?

2.Why were the early uses of gold only decorative?

3.What deposits are found in earth's crust?

Silver

Although silver was found freely in nature, its occurrence was rare. Silver is the most chemically active of the noble metals, is harder than gold but softer than copper. It ranks second in ductility and malleability to gold. It is normally stable in pure air and water but tarnishes when exposed to ozone, hydrogen sulfide or sulfur. Due to its softness, pure silver was used for ornaments, jewelry and as a measure of wealth. In a manner similar to gold, native silver can easily be formed. Silver's symbol is Ag from the Latin argentum.

Galena always contains a small amount of silver and it was found that if the lead was oxidized into a powdery ash a droplet of silver was left behind. Another development in this process was the discovery that if bone ash was added to the lead oxide, the lead oxide would be adsorbed and a large amount of material could be processed. By 2500 BC the cupellation process was the normal mode of silver manufacture.

1.What properties compared with gold are described in the text?

2.What will happen if the lead is oxidized into a powdery ash?

Part III. Plastics

Cellulose-Based Plastics

In 1855, an Englishman from Birmingham named Alexander Parkes developed a synthetic replacement for ivory which he marketed under the trade name Parkesine, and which won a bronze medal at the 1862 World's fair in London. Parkesine was made from cellulose (the major component of plant cell walls) treated with nitric acid and a solvent. The output of the process (commonly known as cellulose nitrate or pyroxilin) could be dissolved in alcohol and hardened into a transparent and elastic material that could be molded when heated. By incorporating pigments into the product, it could be made to resemble ivory.

Bois Durci is a plastic moulding material based on cellulose. It was patented, in Paris in 1855, by Lepage. It is made from finely ground wood flour mixed with a binder, either egg or blood albumen or gelatine. The wood is probably either ebony or rose wood, giving a black or brown result. The mixture is dried and ground to a fine powder. The powder is placed in a

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steel mould and compressed in a powerful hydraulic press whilst being heated by steam. The final product has a highly polished finish imparted by the surface of the steel mould.

1.What was Parkesine?

2.What properties did Parkesine have?

3.What components did Bois Durci get cellulose from?

Synthetic Rubber

Synthetic rubber would also play an important part in the space race and nuclear arms race. Solid rockets used during World War II used nitrocellulose explosives for propellants, but it was impractical and dangerous to make such rockets very big.

During the war, California Institute of Technology (Caltech) researchers came up with a new solid fuel, based on asphalt fuel mixed with an oxidizer, such as potassium or ammonium perchlorate, plus aluminium powder, which burns very hot. This new solid fuel burned more slowly and evenly than nitrocellulose explosives, and was much less dangerous to store and use, though it tended to flow slowly out of the rocket in storage and the rockets using it had to be stockpiled nose down.

After the war, the Caltech researchers began to investigate the use of synthetic rubbers instead of asphalt as the fuel in the mixture. By the mid-1950s, large missiles were being built using solid fuels based on synthetic rubber, mixed with ammonium perchlorate and high proportions of aluminium powder. Such solid fuels could be cast into large, uniform blocks that had no cracks or other defects that would cause non-uniform burning. Ultimately, all large military rockets and missiles would use synthetic rubber based solid fuels, and they would also play a significant part in the civilian space effort.

1.What are the components of the “new solid fuel”?

2.What are the properties of the synthetic rubber?

3.What is the application of the synthetic rubber?

Part IV. Automobile

Fuel

The only fuel used for automobile operation is specially formulated gasoline, even though diesel fuels are used for many trucks and buses and a few automobiles. The things in a good fuel for automobile are proper volatility, sufficient antiknock quality, and freedom from polluting by-products of combustion.

The volatility is reformulated seasonally by refiners so that sufficient gasoline vaporizes, even in extreme cold weather, to permit easy engine starting. Antiknock compounds, principally tetraethyl lead, were added to most gasolines to prevent knocking, a rapid, uncontrolled burning in the final stages of combustion that results in a characteristic "knock," or pinging noise, and may damage an engine or reduce its performance.

Small lead deposits on such places as engine-valve seats improve valve life. Antiknock quality is rated by the octane number of the gasoline and depends primarily on the compression ratio of the engine. However it is also affected by combustion-chamber design and chamber-wall deposits.

1.What permits easy engine starting?

2.What was added to most gasolines en to prevent knocking?

3.What does antiknock quality depend on?

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Maintenance

Maintenance is something most of us ignore, until our vehicle stops functioning, that is. And then we wonder what went wrong, where. Maintenance is one of the most serious aspects of ownership. It determines the longevity, performance and reliability of whichever vehicle you drive. Looking after your vehicle involves more than taking care of its external coat of paint and keeping it clean and shiny.

Maintenance means taking care of all the parts, even those that are inside the bonnet. These are the ones that directly concern the performance of your vehicle. Besides taking it to the service station at regular periods, it is a good idea to go through the owner's manual that will give a fair idea about its routine maintenance.

Checking the battery, keeping a check on the oils, changing the oils, checking the electrical system, are some of the absolutely unavoidable things to keep your vehicle in good shape. Keeping a log book in which you keep all the details regarding repair, maintenance, routine check-ups etc. will not only give you an accurate idea of what needs to be done when.

1.What does maintenance determine?

2.What does maintenance mean?

Frame

The foundation of the automobile chassis is the frame which provides support for the engine, body and power train members. Cross members reinforce the frame. The frame is rigid and strong so that it can withstand the shocks, vibrations, twists and other strains to which it is put on the road.

The frame provides a firm structure for the body as well as a good point for the suspension system. There are two types of frames, namely conventional frames and integral (unibody frames (frameless constructions).

Conventional frames are usually made of heavy steel channel sections welded or riveted together. All other parts of the car are attached to the frame.

In order to prevent noise and vibrations from passing to the frame and from there to the passengers of the car, the frame is insulated from these parts by rubber pads.

It is also important to insulate the frame in order to prevent metal-to-metal contacts. Frameless (unibody) constructions are called so because they are made integral with the

body. The body parts are used to structurally strengthen the entire car. Some unibody frames have partial front and rear frames for attaching the engine and suspension members.

1.Why is the frame rigid and strong?

2.What types of frames are there?

3.By what is the frame insulated from the other car parts? For what purpose?

Part V. Robots and Computers

Computer Use in the Car Industry

All products begin with an idea. In the past, car designers worked first on paper. At a later stage models were made in wood or fiberglass. Now everything is done using CAD (Comput- er-aided design) programs. These programs allow designers to work in two or three dimensions (2-D or 3-D) but most new designers are created using a solid modeling program which allows the model to be viewed from any angle. It can also be viewed by engineers and executives anywhere in the world.

The models have accurate dimensions and the design files can be sent to rapid modeling devices to produce a prototype. Before a single component is produced, programs will have worked out the forces acting on it. Crash conditions can be simulated to test the safety fea-

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tures of the car. Assembly can be simulated to work out the best way of building the car. This saves time and money.

For components such as engine parts, when the design is complete, the file is imported into a CAM (Computer-aided manufacturing) program. Here, all machining operations are planned. The file is then send to a post processor which converts the data into a set of instructions in a form which can be read by Computer numerical controlled (CNC) machine tools. These instructions are fed to a CNC controller which controls the machine tools which shape the finished product.

In complete Computer-integrated manufacturing (CIM) computers control the assembly line and monitor the supply of materials, ordering new supplies when needed. They can calculate when tools need to be replaced.computers also permit changes in a product to be made easily. Orders can be customized to meet the needs of a particular client.

On the assembly line, computer-controlled robots are used for tasks such as welding and painting. Robots with sensors check the finished vehicle for defects. For example, they can check the paint thickness and how well the doors fit.

1.What do CAD / CAM / CIM / CNC mean?

2.List the things computers can do in the design and production of a car.

Robots — the Ideal Workers?

We hear many complaints about work in factories; the work is often boring, heavy and repetitive; the operative doesn’t have to think about the work; he gets no job satisfaction.

The answer is a robot. For many jobs a robot is much better than human operative. Once it has been programmed, it will do its job over and over again. It never gets bored; it works at a constant speed; it doesn’t make mistake and get tired; it can work 24/7 without breaks for food, rest or sleep.

Robots have other advantages, too. You can change the human body, but a robot’s arms, for example, can be made to move in any direction; they can work under water, in poisonous gas, in radioactive areas.

It’s obvious that robots have many advantages over human beings. However, it is also true that humans can do many things that robots can’t. For example, humans can carry out a task without having to be told exactly how to do it first — in other words, they don’t always have to be programmed. Humans can move, but robots are usually fixed in one place. If they are able to move, robots can do it only in a very limited way. Also robots are only just beginning to be able to understand speech and writing.

And we shouldn’t forget that robots owe their existence to humans — we make them, repair them and control them, not the other way round.

1.Define advantages and disadvantages of a man/robot at work.

2.Do you think that robots can ever completely replace people at work? Why?

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Part VI. Graphs

1. Study the diagram below which shows how tensile strength, hardness, and ductility vary with the percentage of carbon in carbon steels.

Fig. 1. Properties of Carbon Steels

2.Answer these questions:

1.What percentage of carbon gives the greatest tensile strength?

2.What happens to ductility between 0,08% and 0,87% carbon?

3.How does increased carbon affect hardness?

4.What is the effect on tensile strength of increasing carbon beyond 0,84?

5.What happens to ductility beyond 0,87 carbon?

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