Английский язык для горных инженеров-механиков. Учебное пособие

4. Combining percussion or rotary action results in hybrid method termed_______and______. 5. Drill, road and bit are______of the drilling system. 6. The fourth component of the drilling system, _______, cleans the hole, controls the dust, cools the bit. 7. Underground percussion is employed for_______and drag-bit rotary for_______.

I.21. Say what paragraph speaks on the aims of rock penetration and rock fragmentation functions.

I.22. Give the general title to the paragraphs 3 and 4.

I.23. Say what paragraph speaks on the basic methods of application of mechanical energy to rock.

I.24. Which of the paragraphs speaks on the importance of the energy loss reduction.

I.25. Entitle paragraph 5.

I.26. Make a plan to the text and speak on drilling or rock penetration using text A and Table 2.

I.27. Look through Table 2 “Classification of Rock Penetration Methods”. All known methods or concepts of rock penetration are listed in it in general order of importance, with those having widest application appearing first. A particular machine employs a particular form of attack and particular method. Try and compose a little text.

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Table 2. Classification of Rock Penetration Methods.

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II

TEXT B. Fragmentation

In mining for coal, metallic, and nonmetallic minerals the process of removing minerals from the earth is called mining excavation. Excavation consists of fragmentation of mineral from their solid state, loading and transporting them to the surface. Fragmentation is accomplished by the use of explosives or mechanical means, the former being most commonly applied. Mechanical fragmentation is used primarily in coal mining, and the loading device is commonly an integral part of the machine. The principal machines are: the continuous miner, auger, coal plow, and coal cutter. There are many variations of them to meet varying conditions in coal seems.

The continuous miner rips the coal by a front-end cutting head comprising a number of continuously revolving chains upon which are mounted hard-metal-tipped cutters or picks. The chains are mounted on a bar which can be rotated horizontally and vertically. The cutter bar frame is mounted on a carriage which in turn is mounted on caterpillar treads. The broken coal is collected by a conveyor or other means of transport.

Augers up to 5ft (1.5 m) in diameter are used under high banks of abandoned steep mines to recover coal to a boring depth of about 200 ft (60 m). The auger is made in sections, the first one having a hard-metal-faced cutting tool that does the cutting as the auger is rotated. The force providing thrust and rotation to the auger is supplied by a diesel engine at the surface. Some machines are self-propelling.

The coal plow or planer was developed in Germany to mine coal by the longwall system. The plow is drawn back and forth along the face and cuts or stabs off the coal in a series of slices. The electric motor moves the plow by means of rotating drum and chain attached to the planer. Broken coal falls to the conveyor, which moves it to the entry. The pneumatic shifters move the conveyor and the plow towards the face as mining advances.

I. Answer the questions.

1.What is mining excavation?

2.What does excavation consist of?

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3.How is fragmentation accomplished?

4.Where is mechanical fragmentation used?

5.What are the principal machines used in fragmentation?

II.2. a) Draw in your note-book the diagram given below and complete it with the names of the continuous mine parts, b) Describe the construction of this machine.

Front-end cutting head

comprise

hard metal tipped cutters

is mounted

is mounted

is mounted

II.3. Describe the work of the auger and the coal plow or planer.

II.4. Give the summary of the text B.

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III

TEXT С Drills

Drills make opening of relatively small cross-section and long length, which are used to obtain samples of minerals during exploration, and to extract natural or artificial solutions or melts of minerals.

Rock drill is a percussion, rotary or combination action steel rod, tipped with a harder metal chisel or rolling gear-like bit. It chips out holes up to 12 in (30 cm) or more in diameter by 125 ft (38 m) or more long from surface and 1–3 in (2.5–8 cm) by 5–200 ft (1.5–60 m) from underground. Crawlers or wheeled carriers are used, and the smaller drills are often attached to hydraulically maneuvered booms. Air or liquids flush out the chips.

Diamond drills. Rotation of a pipe tipped with a diamond bit is used in exploration to penetrate the hardest rocks. Large units make holes up to 3 in (8 cm) in diameter and 5000 ft (1.5 km) or more deep: at the other extreme are units so small that they can be pack-carried.

Water-jet drills. For exploration and blasting in loose or weakly bonded materials, a water-jet washes out a hole as a well-supporting pipe is inserted.

Jet-flame drills. For economical surface blast holes in hard abrasive quartzitic rock, a high-velocity flame is used to small out a hole.

III.1. Write out the determination of a “rock drill”.

III.2. Find out the paragraph speaking on the sphere of application of drills.

III.3. Make up sentences according to the information of the text.

III.4. Give the summary of the text.

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UNIT IV

Materials handling.

Loading and Excavating Equipment.

I

I.1. Find the meanings of the new words from the dictionary.

I.2. Read and translate the phrases without a dictionary.

Cyclic operations, vertical transport, combined machines, excavating equipment, individual machine, surface mining, operating characteristics, working zone.

I.3. Guess the meanings of the words below minding the similarity ol their stems with those in your native language.

Category, bulldozer, function, type, elevator, variety, scene, safe, condition, front, major, locale, maneuver, to dominate, to modify, to summarize.

I.4. Define the common stem in each group of words, translate paying attention to the suffixes. Continue each line if you can.

–to operate, operation, operator ...

–to excavate, excavation, excavator ...

–to hoist, hoisting, hoister ...

–to locate, locale, location...

–to unite, unit, unification...

–to complete, complicative...

–to compete, competitive...

–to handle, hand, handling...

–to elevate, elevator...

–to continue, continuous, continuity...

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I.5. Translate the verbs with the suffix “- fy (-ify)”, form nouns

from the verbs.

to modify–modification

to classify–...

to unity–...

to identify–…

to simplify–...

to intensify–…

I.6. Translate the verbs with suffix “-ate”.

Detonate, dominate, consolidate, circulate, concentrate, rotate.

I.7. Form nouns of the verbs, with suffix “ -er (or)”. What do all these words mean?

I.8.Translate the words with the suffix “-ic”, minding that it may form nouns as well as adjectives:

Electric, climatic, characteristic, cyclic, automatic, metallic, economics.

I.9. Try and translate the names of combined machines.

Rubber-tired scraper, rope-drawn scraper, loader-excavator, boom-type excavator, front-end loader, bucket-wheel excavator, loading-haulage machine, load-haul-dump, tunnel-boring machine.

I.10. Revise grammar “Absolute Participle Construction”. Translate the sentences.

1. Different kinds of exploratory drilling are used, their choice depending on the geological conditions of the deposit. 2. The mine being gassy, flameproof equipment should be used. 3. Transport operations involve

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the removal of waste rock or mineral, the latter being transported to concentration plants, power stations, and railway stations. 4. Draglines being available in a wide range of sizes, they meet varying conditions. 5. Different types of machines are used for underground transport, main trends being towards the use of belt conveyors. 6. At the beginning of the nineteenth century coal-mining was a small but rapidly expanding industry, the coal output reaching only about 10 million tons per annum.

I.11. Read and translate text A.

TEXT A. Materials Handling. Loading and Excavating Equipment

1.All operations involved in excavating or moving bulk material during mining are termed materials handling. In cyclic operations, the two principal operations are loading and haulage, with hoisting when essentially vertical transport is accomplished. In continuous operations, where machines combine breakage and handling functions, cutting, drilling and blasting are eliminated, and extraction and loading are performed in a single function (excavation). In combined loading-haulage machines, materials handling is performed in a single operation.

2.The extraction and elevating of minerals, either broken or in place, is termed loading or excavating. A classification of mine loading-excavating equipment is presented in Table 3. Bases for the classification are the locale of mining (surface or underground) and continuity of operation (cyclic or continuous) Categories and common examples of individual machines are given for each.

3.The variety of equipment may overwhelm the student, certain machines dominating the scene however. For surface mining, shovels, loaders, draglines, and scrapers are in most common use. For underground mining loaders, load-haul-dump units (LHDs), and continuous miners are prevalent. In underground mines with large openings and sufficient headroom, surface equipment-dozers, shovels, trucks, loaders and drills, modified to meet safety and operating conditions-has increasing application.

4.Each category and individual machine has its own operating characteristics. Several have a unique feature: they perform joint functions of

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loading and haulage. Examples of loading equipment that perform substantial haulage are dozers, rubber-tired scrapers, rote-drawn scrapers, and LHDs.

5.Most loaders-excavators are required to operate in three working zones. These zones are digging, maneuvering-transporting and dumping. In stripping overburden or loading ore a boom-type excavator (power shovel, dragline, or bucket wheel) is used. In other conditions scrapers dozers, frontend loaders, or dredges find unique application.

6.The major features of large shovels, draglines and wheel excavators are summarized as advantages and disadvantages in Table 3. These three machines are competitive and commonly used to strip overburden in surface coal mining, being used often in recent years because of their greater range.

I.12. Answer the questions:

1.What is material handling?

2.How do cyclic and continuous operations differ?

3.What are the principal operations in cyclic method?

4.What is loading?

5.What are the main machines used in surface mining?

6.What kind of machines dominate in underground mining?

7.What is the unique feature of loading-excavating equipment?

8.What working zones do they distinguish?

9.What are the advantages of large shovel, dragline and wheel excavator?

10.Can you note the names of some boom-type excavators?

11.Why has the trend been to dragline in recent years?

I.13. Which of the statements are true? Correct false statements.

1.In cyclic operations hoisting is one of the three principal operations.

2.Cutting, drilling and blasting are eliminated in continuous operations.

3.In combined loading-haulage machines handling is performed in a single operation.

4.In underground mines with large openings and sufficient headroom surface equipment are used without any modification.

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5.The extraction and elevating of minerals either broken or in place is termed materials handling.

6.Bases for the classification of loading-excavating equipment are the locale of mining and continuity of operation.

7.For underground mining only load-haul-dump units (LHDs) are prevalent.

8.For surface mining shovels, loaders, draglines and scrapers are in most common use.

9.Most loaders-excavators are required to operate in two working

zone.

I.14. Group the words into four groups: a) nouns, b) adjectives; c) adverbs; d) verbs.

involve, excavate, principal, haulage, essentially, accomplish, breakage, handling, perform, equip, move, continuous, category, sufficient, modify, unique, equipment, scraper, summarize, advantage, strongly, competitive.

I.15. Compose as many phrases as you can, uniting the words of the two columns.

I.16. Fill up the blanks with suitable words from the box. What do they all mean?

loading, breakage, cutting, drilling, blasting, hoisting, haulage, extraction, excavation, handling

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