Английский язык для горных инженеров-механиков. Учебное пособие

I.8. Group the words into three columns according to the pronunciation of the ending “-ed”.

involved, required, bored, distinguished, mechanized, specialized, excavated, inserted, detonated, loaded, mined, freed, reduced, used.

I.9. Translate the sentences minding different functions of the verb

“to be”.

1. Until mining machines were developed, short faces predominated. 2. We say that that the method of mining is rational if it guarantees safety of men and maximum out-put of mineral.3.There special methods of extracting seams which are closed together. 4. Explosives are used for excavating hard rock. 5. In gassy mines each face is to be ventilated with its own air current. 6. It’s necessary tostudy all the factors which influence the choice of the mining methods.7.Mind what is taken into account in selecting haulage system.

I.10. Revise grammar material “Passive Voice”. Change sentences by the model.

Model: In underground mines they use special equipment on a reduced

scale.

In underground mines special equipment on a reduced scale is

used.

1. They divide commercial minerals into three main categories. 2. If the excavation is operated from the surface they call it a surface mining. 3. They obtain samples by trenching, tunnelling and drilling. 4. They classify underground mining into three methods: unsupported, supported and cavinig.

5.Prospecting and exploration accomplish the main goal–finding ore deposit.

6.Power excavators load the broken material.

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I.11. Read and translate text A.

TEXT A. Unit Operations of Mining

During the development and exploitation stages of all mining when natural materials–rock or soil , ore or waste–are excavated from the earth, remarkably similar unit operations are employed. The unit operations are the basic steps employed to produce mineral from the deposit.

The production cycle employs unit operations which are normally grouped in two functions: rock breakage and materials handling. In most mines breakage is accomplished by drilling (rock penetration) and blasting (rock fragmentation).

Material handling is usually performed in tow steps, loading (excavation) and haulage. If considerable vertical lift is involved, then hoisting may be required as well.

Production cycle = drill + load + haul

The cycle of operations in surface and underground mining is distinguished mainly by the scale of the equipment. Mining today is almost totally mechanized. Specialized machines used in both regimes are remarkably similar in principle and function and are to meet the unique needs and conditions.

In modern surface mining, blast holes several inches (mm) in diameters are bored by mobile rotary or percussion drills for the placement of explosives, when consolidated rock must be excavated. The charge is then inserted and detonated to reduce the ore or waste to fragments The broken material is loaded by power excavators or shovels, draglines or wheel type into haulage units railroad cars, belt conveyors, or trucks. Soil and coal are mined in a similar way, although blasting is often unnecessary. In quarrying dimension stone, the blocks are freed without blasting by channelling machines or saws.

In underground mining, the cycle differs little, although equipment on a reduced scale is usually employed. Smaller drill-holes are bored for blasting, and down-sized trains, trucks, shuttle cars, or conveyors are used to haul the ore or coal from the mine.

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To addition to the productive phases of the actual mining cycle, certain auxiliary operations must be performed. Underground these auxiliary operations consist of providing and maintaining adequate roof support, ventilation and air conditioning, power supply, pumping, maintenance, lighting, communications, and delivery of supplies. In surface mining, the first two are not necessary.

Rock breakage–the freeing detaching of large masses of rock from its parent deposit.

I.12. Answer the following questions.

1.What are unit operations?

2.What is the production cycle?

3.What functions are the unit operations grouped in?

4.What steps does rock breakage include?

5.What steps does material handling include?

6.When is hoisting required?

7.What fact distinguishes the cycle of operations in surface and underground mining?

8.What are blast holes bored by?

9.What is the role of blasting?

10.What types of machines are used for loading the broken material?

11.What are the main haulage units?

12.What auxiliary operations must be performed underground?

I.13. Group the information in the order you meet it in the text.

1.The broken material is loaded into haulage units by power excavators.

2.In underground mining compact loading machines and down-sized trains, trucks, shuttle cars, or conveyors are used.

3.The unit operations are the basic steps employed to produce minerals from the deposit.

4.Underground auxiliary operations consist of providing and maintaining adequate roof support, ventilation and air conditioning, power supply, pumping, lighting communications and delivery of supplies.

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5.Breakage is accomplished by drilling and blasting.

6.The production cycle employs unit operations grouped in two functions: rock breakage and materials handling

7.The cycle of operations in surface and underground mining is distinguished by the scale of equipment.

8.Blast holes are bored by mobile rotary or percussion drills.

9.Materials handling is performed in two steps: loading and haulage.

I.14. Which of the statements are true? Correct false statements.

1.The unit operations are the basic steps employed to produce

minerals.

2.The unit operations are grouped in four functions.

3.Breakage is accomplished by drilling and blasting.

4.Materials handling is performed in two steps.

5.The cycle of operations underground doesn't differ from that in

surface.

6.Wheel type power excavators are haulage units.

7.Rail road cars, belt conveyors, trucks are transporting machines.

8.Compact loading machines are used underground.

9.The broken material is loaded by the shovel, dragline, or wheel type power excavators.

I.15. Compose as much phrases as possible.

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I.16. Finish the sentences below choosing the right variant.

1.Unit operations in mining are grouped...

...in two functions

...in three functions

...in several functions

2.The cycle of operations is distinguished...

...by the sequence of functions

...by the scale of equipment

...by the number of functions

3.The broken material is loaded...

…by trucks and railroad cars

...by power excavators

...by rotary or percussion drills

4.The shovel, dragline, or wheel type excavators are used...

…for boring blast holes

…for transporting broken material

...for reducing ore waste to fragments

I.17. Fill up the blanks with the appropriate words from the text.

1.___________is accomplished by drilling and blasting. 2 Materials handling is performed in tow steps:_____________. 3. If considerable vertical lift is involved, then___________may be required. 4___________employs unit operations grouped in_____rock breakage and materials handling. 5.__________ used in both regimes are remarkably similar in principle function. 6. Blast holes are bored by mobile or rotary drills for_________.7. In underground mining equipment on a __________ is usually employed.8. To addition to the productive phases of the actual mining cycle, certain______must be performed. 9. Coal by surface and underground methods.

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I.18. Compose sentences using words of the table below.

I.20. Say what paragraph speaks on the sequence of operations in surface and underground mining, and equipment used in every of them.

I.21. Give the title to the last paragraph.

I.22. Find two paragraphs which speak on the similarity and difference between surface and underground mining.

I.23. Draw in your notebook two diagrams like given below and fill up the boxes using the information of the text A.

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A)

auxiliary operations and equipment

?truck

I.24. Speak on the unit operations of mining using all the

information you know.

II

TEXT B. Requirements for Design and Construction of

Mining Machinery

Mining machinery–apparatus used in removing and transporting valuable solid minerals from their place of natural origin to a more accessible location for further processing or location.

Many of mining machines are identical to those used for excavating in the construction industry. In a wider sense mining machinery could also include all equipment used in finding (exploring and prospecting), removing (developing and exploiting), and improving (ore dressing, milling, concentrating or refining) valuable minerals. Perhaps those machines, most often considered as uniquely mming machines, are drills, mechanical miners, and specially adapted material handling equipment for use in mining

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underground or on surface. All components of mining machines including primary mechanism, controls, means of powering and frame require the following features to a much greater extent than do other machines.

Ruggness. Equipment is handled roughly, frequently receiving severe and sudden shock from dropping, striking, and blasting vibration; overloading is common, and long life is demanded by the economics of mining.

Weather resistance. Operations extend over a wide range of climate and altitude.

Abrasion resistance. Mineral include some of the hardest substances known. Dust and fine particles are always present.

Water and corrosion resistance. Moisture and water, often acidic, are common in mining operations.

Infrequent and simple maintenance. Equipment is often scattered and in locations with restricted access. Trained mechanics and repair parts are generally limited in availability because of the remoteness of operation.

Easy disassembly and reassembly. Access to the machine at the site of operation is frequently limited. Also, the working space near it and mechanical aids to moving or lifting it may be limited.

Safety. Mining has had a poor safety record. As a result, most governments have testing bureaus, inspection agencies, and enforcement laws for the approval of mining equipment

Simplicity of operation, low initial cost, and low operation cost are also desirable features of mining machines.

Underground Requirements

Machines operated underground must meet special design requirements.

Low ventilation demand. Quantity and geometry of passageways for air .ire rather rigidly fixed, that's why high air consumption is a problem and noxious gases cannot be readily dispersed. Heat removal is a problem in deep mines.

Compactness. Space is at a premium, especially height, particularly in bituminous coal mines.

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Easy visibility. Most operating areas are lighted only by individual cap-mounted or hand-held lamps.

Hand portability. Units or components must frequently be hand carried into an operating area.

Absence of spark and flame. Equipment is often used in or near explosives, timber supports and natural or man-made combustible gas or dust.

II.1. Answer the questions.

1.What is mining machinery?

2.What does the term “mining machinery” mean in a wide sense?

3.What machines are considered to be uniquely mining machines?

4.What are the main components of mining machines?

5.What mam features do mining machines require?

6.Why is ruggness required?

7.Why is weather resistance required?

8.Why are abrasion, corrosion and water resistance required?

9.What are the requirements to the maintenance and construction of mining machines?

10.What other features of mining machines are also desirable?

11.What are special requirements to the machines operating underground?

II.2. Complete each sentence with the suitable word or phrase from the box. Put “that's why” instead of dots.

ruggness, weather resistance, abrasion resistance, infrequent and simple maintenance, safety, easy disassembly, water and corrosion resistance

1. Mining equipment may receive severe and sudden shock.......it requires _____. 2. One of the requirements to mining machines is_______,

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....... trained mechanics and repair parts are limited because of the remoteness of operation. 6. Mechanical aids to moving or lighting machinery

II. 3. Fill up the boxes and speak about general requirements for mining machines and special requirements for underground mining

General requirements for mining

А)

B)

Special requirements for underground mining

III

TEXT С. Mining Power

Power is applied to mining in six distinctive ways: electricity, diesel power, compressed air, hydraulic power, steam power, and hydroelectric.

Electricity. Both alternating and direct electric current are used in modern mining. Direct current (dc) is used for locomotive haulage and for major portion of underground coal operations, because of the high torque developed in dc series motor under heavy loads and starting. Alternating current (ac) is used less extensively although some mines employ both in a dual system.

Converting ac to dc underground may be accomplished by several methods. A 250 or 500 volt substation can be provided by converters, motor-

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