Английский язык для горных инженеров-механиков. Учебное пособие

generator sets, mercury-arc rectifiers made of selenium, germanium, or silicon. Portable conversion units offer increased convenience and efficiency.

Trolleys and feeder lines supply power throughout the main roadways. These distribution lines should not be extended more than 3500-4000 ft from the power source to avoid low voltage at the end of the line.

Sectional ization is a method of distributing mine power so that power cables can be isolated for reason of faults or repair without shutting off the main supply to several working sections. For main distribution, circuit, breakers, disconnect switches, and various overcurrent protective devices are essential for properly installed sectionalisation. Power is distributed by pole lines or cable systems, or a combination of the two.

Diesel power. This type is rapidly gaining favour in metal and noncoal mining because of its flexibility. Requirements for equipment using diesel power include explosion proof housings, mine ventilation necessary to dilute exhaust gases, control of hot exhaust gases and surface temperature, concentration of toxic constituents in exhaust gases.

Compressed air. Pneumatic power is utilized in a variety of applications, mostly in the metal and noncoal fields. It is used for power drills, and hoists, pneumatic tools, diggers, mine ventilation, starting diesel engines, and coal preparations. Compressed air is used in coal mining for blasting.

Hydraulic power. For mining, hydraulic applications are rather limited in usage and may employ either water or oil as a fluid.

Steam power. Although formerly used to drive compressors, hoists, generators, and other equipment, steam is now rarely used in mining but has definite, although limited, application in some coal mines in which there is an abundance of waste fuel or unmarketable coal.

Hydroelectricity. Some hydroelectricity has been used for normal electrical mining power, but mostly it is used for processes beyond the mining operations such as benefication, smelting, and refining.

III.1. Answer the questions.

1. What are the six distinctive ways of applying power to mining?

2.Why is alternating current used less extensively?

3.How do they convert ac to dc underground?

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4.By what means do they conduct power through the roadways?

5.How is power distributed?

6.What are the requirements for equipment using diesel power?

7.Where is pneumatic power utilized mostly?

8.What fluid is employed in hydraulic application?

9.Where is steam power mostly used?

III.2. Fill up the boxes with the names of the main ways of applying

power in mining.

Power sources

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UNIT III

Rock Breakage.

Drilling and Fragmentation

I

I.I. Find the meanings of the new words from the dictionary

I.2. Guess the meanings of the phrases without a dictionary minding the similarity of their stems with those in your native language.

Basic mechanism, functional component drilling system, prime mover, energy source, original form, mechanical energy, physical components, mineral product, hybrid method, hydraulic energy.

I.3. Read and translate the phrases.

Finished mine opening, rock breakage function, rotary action, combustion engine drive, rock penetration, fragmentation function, pneumatic engine drive.

I.4. Read the nouns with the suffix “-er” and translate them. From

1.5. Translate the words, paying attention to the prefixes and suffixed forming different parts of speech. Use a dictionary.

to apply – applicator – application

to move – mover – movement – removal, movable, removable

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place – to replace – placement – emplacement

to form – to perform – performance – reform, formation to stabilize – stabilization – stable – stability – unstable to rotate – rotation – rotor – rotary

to mechanize – mechanic – mechanization – mechanical – mechanics

I.6. Form adverbs from adjectives with the suffix “ly” and

I.7. Translate the words below which can be nouns as well as verbs. Then translate the sentences.

drive, result, support, aim, function, term, drill, control, fragment

1.The main function of a drill is to convert energy from the original form into mechanical energy.

2.A drill functions as a prime mover.

3.An operator controls the work of the whole system.

4.A strict control is necessary to ensure the continuous work of the whole system.

5.Fragmentation aims to loosen and fragment large masses of material.

6.Small fragments of material are then loaded and transported.

I.8. Form verbs from adjectives using the ending “-en”, which

makes verbs meaning “to cause” or “to have”. Translate the words.

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I.9. Translate the composite terms. drag – bit – action type roller – bit – action (type) roller – bit – rotary drilling rotary – percussion drilling

down – hole drilling front – end cutting head

hard – metal – tipped cutter

I.10. Translate the sentences defining functions of the “-ing”–form.

1. Man realized the heating quality of coal long ago. 2. Coal is a source of lighting and heating. 3. Cutting coal is performed by cutting chains. 4. Many different factors are taken into account in choosing a suitable cutting machine. 5. When choosing a cutting machine engineer should take into account different factors. 6. The essence of mining in extracting mineral from the earth is to drive or construct an excavation from the existing surface to the mineral deposit. 7. In quarrying dimension stone the blocks are freed without blasting by channeling machines.

I.11. Translate the following sentences minding different functions of Participle II.

1. The type of mining method used has a great influence upon the nature and extent of the environmental impact. 2. Two reliable mining machines are used for top slicing: a shearer or a plow. 3. A great amount of dynamite has been used. 4. The long wall mining system for sublevel caving consists of a shearer or a plow associated with a conveyor. 5. In long-wall mining system a shearer or a plow is associated with a conveyor. 6. When associated with conveyor a shearer is more efficient. 7. Holes are usually blasted with dynamite and standard caps and fuses. 8. The material blasted is called muck. 9. When blasted the material is broken into small fragments.

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I.12. Read and translate the text.

TEXT A. Drilling or Rock Penetration

1.Generally, two different kinds of rock breakage operations are performed in mining. In rock penetration a direct hole or kerf is formed usually mechanically but sometimes hydraulically or thermally, for the placement of explosives in blasting or for other purpose requiring small holes, to produce a finished mine opening or tunnel or to extract a mineral product of desired size and shape. In contrast, rock fragmentation aims to loosen and fragment large masses of material by chemical, mechanical, or hydraulic energy,

2.Although operating on different scales, penetration and fragmentation function by applying energy through a variety of similar basic mechanisms to break rock. The application of mechanical energy to rock can be performed basically by percussive or rotary action. Combining the two results in hybrid methods, termed rolled-bit rotary and rotary-percussion drilling.

3.There are four main functional components of a drilling system (and of most other penetration systems). They are related to the utilization of energy by the drilling system in attacking rock in the following ways:

1) the drill is the prime mover, converting energy from its original form (fluid, electrical, or pneumatic, or combustion engine drive) into mechanical energy to actuate the system.

2) the road (or drill steel, stem, or pipe) transmits energy from the prime mover or source to the bit or applicator.

3) the bit is the applicator of energy in the system, attacking rock mechanically to achieve penetration.

4) the circulating fluid cleans the hole, controls dust, cools the bit, and at the same time stabilizes the hole.

4.The first three are physical components of the drilling system, controlling the penetration process, while the fourth is supportive to penetration trough removal of cuttings.

5.In surface mining, roller-bit rotaries and large percussion drills are the machines in wide current use. Underground, percussion is employed for

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hard lock and drag-bit rotary for coal and soft to medium-hard rock. Rock cutting and boring machines utilize drag-bit or, roller-bit action.

6. In commercial drilling machines (Table 2), attention has focused on reduction of energy losses in transmission. This has led to the introduction of down-hole drills, and the roller-bit rotary (electrodrill and turbodrill) type. They replace mechanical energy transmission with fluid electrical transmission which usually results in more energy reaching the bit and faster drilling.

I.13. Answer the questions.

1.What is a hole or kerf formed for?

2.What does rock fragmentation function?

3.How do penetration and fragmentation function?

4.What are the methods of application of mechanical energy to rock?

5.What are the hybrid method of application of energy to rock?

6.What are main functional components of a drilling system? What are they related to?

7.What is the role of the drill?

8.What function does the rod perform?

9.What is the bit?

10.Why is the fourth component of a drilling system called “supportive”?

11.What drilling machines are used in surface and underground

mining?

12.Why do they replace mechanical energy transmission with fluid or electrical transmission?

I.14. Do you agree with the statements below? If not, change them

so that they are true.

1.Rock penetration is one of two rock breakage operations performed in mining.

2.Penetration and fragmentation function by applying energy through different mechanism.

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3.The application of mechanical energy to rock can be performed basically by rotary action.

4.There are two main functional components of a drilling system.

5.Underground percussion is employed basically for medium-hard

rock.

6.A hole or kerf is only formed mechanically.

7.Rock-cutting and boring machines utilize drag-bit or roller-bit

action.

8.The use of mechanical energy transmission results in more energy reaching the bit and faster drilling.

9.Roller-bit rotaries and large percussion drills are widely used in surface mining.

I.15. Group the information in the order you meet in the text.

–In rock penetration a direct hole or kerf is formed usually mechanically but sometimes hydraulically or thermally.

–Underground percussion is employed for hard rock and drag-bit rotary for coal and soft to medium-hard rock.

–Rock fragmentation aims to loosen and fragment large masses of material.

–The drill is the prime mover, converting energy from its original form into mechanical energy.

–Penetration and fragmentation function by applying energy through a variety of similar basic mechanisms to break rock.

–There are four main components of a drilling system.

–The rod transmits energy from the prime mover to the bit.

–The bit is the applicator of energy, attacking rock mechanically

–The application of mechanical energy to rock can be performed basically by percussive or rotary action.

–In commercial drilling machines attention has focused on reduction of energy losses in transmission.

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I.16. Compose and translate phrases by combining: a) adjectives +

I.17. Change phrases by the model, translate them.

Model: losses of energy – energy losses

placement of explosives – product of desired size – application of mechanical energy – method of energy application – utilization of energy – components of a drilling system – circulation of fluid –

process of penetration – reduction of energy –

I.18. What terms are used to determine the following?

1. The applicator of energy in the drilling system, a.fragment attacking rock mechanically to achieve penetration.

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I.19. Fill up the blanks with the appropriate prepositions from the

box.

to, by, from, for, of, into, with

1.A hole or kerf is formed ... the placement of explosives or ... other purposes.

2.Rock fragmentation aims ... loosen and fragment material ...

chemical, mechanical, or hydraulic energy.

3.Penetration and fragmentation function ... applying energy through a variety of similar basic mechanism to break rock.

4.The application ... mechanical energy to rock can be performed basically ... percussive or rotary action.

5.The drill converts energy ... its original from ... mechanical energy.

6.The rod transmits energy ... the prime mover ... the bit or applicator.

7.They replace mechanical energy transmission ... fluid or electrical transmission.

1.20. Fill up the blanks with the appropriate words or phrases.

physical components, mineral product, hard rock, percussive or rotary, large masses of material, mine opening, roller-bit rotary drilling, rotary-percussion drilling, circulation fluid, coal and soft-to medium had rock.

1.A kerf is performed to produce a finished_______or tunnel, or to extract ___.

2.Fragmentation aims to loosen and fragment_______. 3. The

application of energy to rock can be performed by______action.

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