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AUTOMATION AND ROBOTICS

1.The introduction of comprehensive production automation is believed to increase labour productivity in basic areas of the national economy, reliability, quality and competitiveness of the output, as well as to achieve a higher technological level and efficiency of production processes. At the same time it reduces the use of manual and unskilled labour.

2.One of the ways to achieve automation is a wide-scale application of industrial robots. We know the term «robot» to cover a class of computercontrolled machines which follow some pattern of behavior on the basis of their program. Their basic components are: the manipulator, the control and the power supply.

3.In production processes industrial robots may be used for different purposes: 1) as a means of flexible automation of the basic technological equipment (presses, furnaces, etc.); 2) as a means for performing auxiliary operations (transportation, removal of wastes); 3) as basic technological equipment (to carry out assembling, welding, painting and other operations); 4) as a means of inspection. In a typical inspection job, using a sensor the robot determines whether the inspected part meets the quality specifications.

4.At present there are more complicated robots having a nervous system and organs to see and to touch different objects. As we know industrial robots made their first appearance in mechanical engineering. It is the area where they are being used most extensively up to our days.

5.Robots are expected to have a wider application in technologies characterized by heavy or dangerous working conditions. They also replace man in jobs requiring monotonous or repetitive motions. In general, the structure of the fleet of industrial robots in each country is determined by the structure and orientation of industry, the state and the cost of manpower, economic conditions and so on.

IV. Прочитайте 5-й абзац текста и ответьте на вопрос: Does the structure of the fleet of industrial robots affect the structure of the country’s industry? Запишите и переведите вопрос и ответ.

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III. ТЕКСТЫ ДЛЯ ЧТЕНИЯ

ДЛЯ СТУДЕНТОВ ГОРНЫХ СПЕЦИАЛЬНОСТЕЙ

Тексты для самостоятельного чтения

1. COAL, ITS TYPES, AND USES

Everyone knows coal to be one of the most important natural fuels. It took nature millions of years to form coal by the slow decomposition of vegetable matter buried in the Earth. Like petroleum and natural gas, coal is carbon-based fuel. Scientists established it to consist mostly of carbon, hydrogen and oxygen combined in complex groupings.

According to the amount of heat it produces (which is called calorific or heat value [теплотворность]), coal is classified into four ranks, or types. The heat value of coals depend on their hardness or on the amount of fixed carbon they contain.

The softest coal is lignite or brown coal followed by sub-bituminous coal containing much less moisture than the first. Both are used as an ordinary fuel, mostly to produce steam and electricity at electric power stations. Soft coals are also divided into coking and non-coking ones.

Bituminous coal with a high heat value and little moisture is widely used both to generate electricity and to produce coke used in steel industry. It is the world’s most abundant coal. The hardest coal, anthracite, has a very high heat value. Burning slowly it makes a good home heating fuel.

Coal is considered to be hard if it contains about 6 per cent of volatile matter. When burning it gives a great deal of heat without producing much smoke or flame. In general, the harder the coal, the less moisture it contains and the more efficient it is as a fuel.

2. HISTORY OF RUSSIAN SCIENCE OF MINING

Coal has long been accepted as one of the main sources of power. Neither industrial enterprises, nor electrical power plants would be able to operate without coal. As fuel it is widely utilized in the domestic economy. Being a valuable raw material it is used to manufacture a variety of chemical products, including coke and gas. That’s why great attention is to be paid to the coal mining industry.

The history of Russian coal mining goes back to the far-off times. The theory and practice of mining and smelting were first systemized by M. Lo-

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monosov in his book «First Principles of the Science of Mining» (1742). He considered the science of mining to be of vital importance to the national economy. The development of the Russian mining school had been greatly affected by that book and other papers dealing with geology and mining.

The most prominent M. Lomonosov’s followers are considered to be A. Karpinsky, B. Boky, M. Protodyakonov. The first of them studied the problems of geological history of the country’s European part. It was him who worked out the theory of organic origin of coal. Boky is known to have developed the analytical method of mine planning. Protodyakonov proposed a new classification of rocks based on numerical coefficients.

At present the Russian scientists are making great efforts to the further development of the theory and practice of both geology and mining. It is very important because the world’s coal production is expected to grow from 4,125 mln tons in 2000 to 7,700 mln tons in 2025.

3. KUZNETSK COAL FIELD

Kuznetsk coal field is unique in the size of its coal reserves, ranks of coal as well as the diversity of mining technologies employed. It gives 39 per cent of the country’s production of coal and for 69 per cent of coking coal.

Kuzbass is known to have more than one century history of coal industry development. There are 25 coal-containing areas in the region but only 17 of them have been or are being exploited. The greatest deposits are located in the Leninsk, Erunakovsk, Tom-Usinsk regions. Geologists suppose the Erunakovsk deposits only to be equal to those of the entire Donbass.

Since the beginning of mining in the Kuznetsk Basin, 5 billion tons of coal have been extracted. Taking into account that the deposits are evaluated by geologists to be about 725 billion tons, this makes less than 1 per cent of the coal reserves. That is, at an annual production of 150 mln tons (even allowing for 50% loss), the Kuzbass coal reserves would be sufficient to cover coal needs for an actually unlimited period of time in future, far exceeding the medium-term forecasts on world fuel sources.

Near half of the deposits are coking coals. Brown and anthracite coals are also available. The coal characteristics are so wide that they can meet the needs of different branches: metallurgy, power engineering, chemistry. The quality of Kuzbass’s coal is said to be the best in the world.

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One of the special geological features of the Kuznetsk Basin is that of great variety and complexity of coal seam bedding. This factor resulted in the necessity of a wide range of techniques to get coal.

4. COAL MINING IN RUSSIA

The Russian Federation was estimated to have as much as 4.4 trillion tons of coal which makes 30 per cent of its world’s reserves. Being one of the leading heavy industries of Russia, coal mining has always been developed together with the country’s national economy. Proper organization of operation requires adequate planning, safety, maintenance, labour force as well as estimation of the coal quality. Hence, a lot of specialists should be employed in industry. For example, transportation of men and coal is the responsibility of the mine manager and the section foreman. The chief electrician is responsible for the maintenance of equipment.

There are various methods of coal getting, but the main difference is made between opencast (open-cut) mining and underground one.

Opencast mining, although it is much cheaper than underground, may be used only when coal seams either come out to the surface or are near it. In this case hydraulic methods and excavators are widely used to get coal.

When coal is far (sometimes at a thousand feet depth) from the surface it has to be worked by underground mining. Among the underground methods there are room-and-pillar (камерно-столбовой), longwall (выемка лавами) advancing, longwall retreating, level system and some others.

In early days coal was worked by the miner lying on his back and cutting the coal with a pick. Today many mining processes are mechanized, powerful coal-cutting machines having replaced the miner. Steady increase of coal output would be impossible without the introduction of the improved and highly efficient methods as well as the extensive development of mechanization and automation.

5. COAL MINING DEVELOPMENT IN KUZBASS

Coal mining industry in Kuzbass includes over 70 mines, about 25 collieries and 17 preparation plants. Nearly 70% of the coal mined is supplied to all regions of Russia as well as to the countries of the Commonwealth of Independent States.

In the earliest days coal was mined with the «obushok» coal-picks. The 1930s are considered to be the start of mechanization. For many years a panel system had been used. It was invented by N. Chanakal to mine the

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thick and steeply inclined coal seams, mostly in the Prokopjevsk-Kiselevsk mining district, rich in coking coal.

Mining combines introduced in 1940-1950 for slightly inclined coal layers were later replaced by powerful mechanized complexes. Coal winning done by complexes makes up about 40% of the total coal output.

Many of the Kuzbass’s coal deposits allow open pit extraction. The first open-pit colliery started operating in 1948. Since then this method has got a wide-scale application. It has a lot of advantages, a major disadvantage being that of ruining the earth’s surface and small rivers. To overcome this problem open-cast mining should be combined with the land recultivation.

The end of the 1950s saw the first hydraulic mine. To break and transport the coal to the surface water has to be pumped under a high pressure. If used for steep layers, the method may have a fine future. We know of further development of so-called underground gasification method, the main idea of which is to burn the coal underground to produce gas fuel.

Thus, Kuzbass is believed to be the only coal mining area where all known technologies of coal extraction are used.

6. COAL PREPARATION

Coal preparation (обогащение) is a technological process aimed at raising the coal quality. When extracted coal is a mixture of lumps of different sizes and ranks, having various proportions of dirt, which comes from the seam and from the roof and the floor of the face (забой). Therefore, the preparation plant has to deal both with coal and rock lumps, sometimes weighing 100 pounds or more, and with fine dust.

There are different methods of coal preparation or cleaning, i.e. the separation of dirt. The simplest one, which begins in the mine, is mechanical cleaning, that is, the removal of impurities by mechanical units such as dustsuppressors, for example.

At present, when mines apply mechanized loading of coal onto conveyors, little sorting of dirt can be done underground. That’s why mechanical methods to remove the dirt, to size and to clean the coal on the surface have become an essential part of every modern colliery.

Sizing and sorting are usually performed on the screens. Screening is a process by which coal particles of different size are separated into groups with particles of the same size. It is generally done by passing the coal through a number of screens, each one having the openings of one size only. Cleaning is done either in the coal-washing or in dry-cleaning plant. The

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choice and position of the coal-preparation plant depends on the quality of the coal extracted.

The task of coal preparation is to treat it in such a way as to produce the maximum quantities of high-quality coals by the most economical means.

Тексты для чтения и анализа в аудитории

1. COAL EXTRACTION AND UTILIZATION

Man realized the heating quality of coal long ago. Coal is most commonly used for producing electricity, for heating and powering industrial facilities, for making steel. Being the basis for most branches of industry, it is widely used to drive powerful vessels and locomotives as well as in metallurgical industry. Chemicals derived from coal are used in the manufacture of nylon, paints, plastics, synthetic rubber, aspirin and thousands of other useful products.

The world’s coal production is expected to grow, and its share in world’s power generation will increase from 37 up to 40 per cent in 2010. Prospected coal reserves in the world are estimated to be sufficient for the next 250 years whereas the reserves of gas and oil will be depleted in about 70 and 40-50 years, respectively.

The countries with the largest coal deposits are China, Russia and the USA, having about 45, 30 and 23 per cent of the world’s total reserves, respectively. It should be said, however, that while coal production and consumption in China and the USA tend to grow, in Russia there is a tendency to decreased production.

In Russian coal mining industry there are some first-priority problems to be solved. One of them is the introduction of advanced technologies which is a multi-purpose task. Non-traditional methods of coal getting include hydroextraction and underground gasification, production of coal slurry, deep processing of coal on site, extraction and utilization of coal seam methane, etc.

It would be impossible to apply up-to-date technologies without suitable equipment. Hence, there is another problem, that of the replacement of outdated, inefficient, environmentally dangerous equipment by advanced ones.

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2. MINING TECHNOLOGIES IN KUZBASS

We know Kuzbass to employ both underground and open-cast mining methods.

In underground mining the most wide-spread technology of mine opening is by means of vertical shafts. The level system seems to be used on a wider scale as well. According to this system the coal seam is cut into pillars as long as 800 m or more, and the coal face is advancing either down or up the raise. In mining flat and inclined, thin and medium-thick seams the longwall retreating is used.

To win coal the miners have at their disposal integrated face equipment sets, continuous miners, heading machines, drilling, loading and transportation equipment. Some mines have been completely switched over to a conveyor transportation of coal. Locomotive haulage is based on electric locomotives and large-capacity mine cars.

Open-cut mines make a wide use of hydraulic mining. They operate new excavators with a bucket capacity of 10-15 cubic meters, powerful dump trucks and drilling equipment. Hydraulic mining and hydraulic transportation are being employed on a wide scale.

It should be noted that major changes have taken place in the equipment and techniques of coal preparation. As a result of improvements in screening, washing, flotation, filtration, concentration and other processes, the output at some preparation plants has increased by more than 30 per cent. The capacity of the screens and cleaning plant depends upon the output of the mine. Inadequate capacity of the coal-preparation plant causes delays and loss of output.

A major problem of coal-mining enterprises is throwing off into the atmosphere up to 2 billion cubic metres of the methane gas. It is as much as 35% of the annual consumption of natural gas by the Kemerovo region. That’s why the nearest task is to increase the extraction and utilization of the methane from the coal deposits.

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ДЛЯ СТУДЕНТОВ ЭЛЕКТРОТЕХНИЧЕСКИХ СПЕЦИАЛЬНОСТЕЙ

Тексты для самостоятельного чтения

1. ELECTRIC POWER

Everyone knows electric power to be generated by converting heat, light, chemical or mechanical energy to electrical one. Most electrical energy is produced at large power stations by means of converting mechanical energy or heat. The mechanical energy of falling water is used to drive turbine generators at hydroelectric stations, and the heat derived by burning coal, oil, or other fossil fuels is used to operate steam turbines or internalcombustion engines that drive electric generators. Also, the heat from the fissioning of uranium or plutonium is used to generate steam for the turbine generator in a nuclear power plant.

Electricity generated by the conversion of light or chemical energy is used mainly for portable power sources. For example, a photoelectric cell converts light energy to electrical one for operating the exposure meter (экспонометр) in a camera, and a lead-acid battery converts chemical energy to electrical one for starting an automobile engine.

Electricity is believed to be clean, inexpensive, and easily transmitted over long distances. Since the 1880s it has had an ever-increasing role in improving the standard of living. It would be impossible to operate numerous pumps, elevators, power tools, furnaces, refrigerators, air-conditioners, radios, television sets, industrial machinery, and many other kinds of equipment without electricity. It has been estimated that in developed countries about 43 per cent of the electric power generated is used for industrial purposes, 32 per cent – in homes, and 21 per cent – in commercial enterprises.

2. VARIETIES OF ENERGY

In the world there are many different sources of energy, both potential and kinetic. One of them is water falling from a high level such as an upland lake. Another one is wind or moving air. Other sources include sea tides, heat from subterranean sources, the energy of the atom as well as coal and oil deposits.

But all these sources and stores of energy are not equally useful to mankind. Moreover some of them such as coal and oil can never be replaced by us when once exhausted. On the other hand, stores of high level water are