Английский язык для горных инженеров-механиков. Учебное пособие

1. In cyclic operations machines perform_______and_______. 2. When essentially vertical transport is accomplished________is performed. 3. In continuous operations machines combine________and________functions.

4.In continuous operations_________,_______and________are eliminated.

5.Combined loading-haulage machines perform materials_______ in a single operation. 6. The extraction and elevating of monorails is termed loading or_______.

I.17. Which of the machines are commonly used for surface (1) and for underground mining (2).

plow, loader, shovel, truck, LHD, continuous miner, dragline, drill, dozers, auger, rubber tired scraper, dredge, borer, shearer, bucket-wheel excavator.

I.18. Compose sentences.

I.19. Fill up each blank with the suitable preposition, translate the sentences.

in, of, for, by

1.....surface mining shovels, loaders, draglines and scrapers are prevalent. 2.....continuos operations extraction and loading are performed.....a single function.3. Bases.....the classification.....mine loading-excavating

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scrapers, rope-drawn scrapers and LHDs. 6.A boom type excavator is

I.20. Look through Table 3 and speak on advantages and disadvantages of shovels, draglines, and bucket wheel excavators. Say which of the paragraphs in the text speak on them.

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

I.22. Entitle paragraph 3.

I.23. Which of the paragraphs speak on machine functions in cyclic and continuous operations?

I.24. Make a plan to the text A and retell it.

II

II.1. Read text В and choose the most suitable title.

1.Power shovels.

2.The advantages of draglines.

3.The construction of shovels and draglines.

4.Power shovels and draglines.

5.The principle of work of draglines and shovels.

6.Working capacity of draglines and shovels.

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Table 3. Comparison of Features of Shovel, Dragline, and Bucket

Wheel Excavator.

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TEXT В

1.Shovels in open-pit mines range from small machines equipped with 2 yd (1.5 m) buckets to large machines with 36 yd (27.5 m) buckets. A 6 yd (4.6 m) shovel will, under average conditions, load about 6000 tons per shift. However, the nature of the material loaded will have a significant effect on productivity. If the material is soft or finely broken, the shovel productivity will 1 be high.

2.The modern power shovel is full-revolving, mounted on tractor and operated by electric motors, diesel engine or gasoline engine. It is mobile unit moving under its own power and handled by one operator. Its principal motions are the swing about its axis, the crowding action as the dipper cuts into the bank, the final swing to dumping position, and the operating of the dipper door to discharge the content of the dipper. The dipper is provided with a cutting edge i and with teeth for tearing and cutting into the bank and for handling coarse loose rock.

3.The power shovel excavates from the level upon which the machine stands to a bank height determined by the highest position of the bucket: it loads material into cars, belt-conveyer hoppers, or other units.

4.Although it competes with the front-end loader, dragline, hydraulic excavator, and other excavating machines the shovel is still the work horse of the surface mining industry.

5.A dragline is similar to a power shovel, but uses a much larger boom. A bucket is suspended by a steel cable over a sheave at the end of the boom. The boom is mounted on a heavy steel frame that can be rotated 360 degrees. The boom angle can be adjusted to digging conditions. The bucket is cast out toward the end of the boom and is pulled back by a hoist together with a load of material which is deposited in an ore haulage unit or on a waste pile. Buckets vary in weight to suit digging conditions: heavier buckets with the weight concentrated close to the cutting edges are required for hard digging.

6.The dragline is a versatile machine. It will dig noncoherent and wellfragmented blasted material but not coarsely broken or compact materials. It will excavate below water. Short-boom draglines are used in coal stripping

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overburden excavation in soils, sands and gravels. Dragline capacity depends upon the machine size and type, the operating and digging conditions.

7. Draglines are available in a wide range of sizes to meet varying conditions. They range in size from machines with buckets of a few cubic yards capacity to machines with buckets of 500 yd (115 m) capacity. Bucket capacity up to 25 yd (weight 35 tons plus load 65 tons) and booms up to 250 ft in length represent the common size.

II.2. Answer the questions:

1.What may be the capacity of shovels' buckets?

2.What is the capacity of a 6 yd shovel?

3.What factors can change the shovel productivity?

4.Is a power shovel a versatile machine?

5.What are the principal motions of power shovels?

6.What power source is used to move a shovel?

7.What is the main difference in construction between a shovel and a dragline?

8.Why do buckets vary in weight?

9.On what is the bucket cast?

10.Can a dragline dig coarsely broken materials?

11.What are the capacities of a common size dragline?

12.How wide is the range of sizes of draglines?

II.3. Say what paragraphs speak on the boom and the bucket of a dragline.

II.4. Find the paragraphs which speak on the conditions in which a shovel and a dragline will dig.

II.5. Say what paragraphs speak on size of shovels and draglines. Compare their capacities.

II.6. Complete the table below using the information of the Text В and of the Table 3

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III

TEXT С

The potash seam is worked using a specially designed double-drum shearer built in MDPA’s central workshop. These machines are unidirectional in operation, hauling themselves along the face by a capstan working on a chain anchored at the face-ends. The machine cuts the ore as it works the face from the tail gate to the main (conveyor) gate, and returns idle.

The lower drum is the leading drum, cutting the bottom part of the seam with its picks working upwards. Ideally, the machine is adjusted so that the lower drum cuts just to the underside of a relatively hard central anhydrite band which, like all the other subbeds in the seam, is remarkably persistent throughout the deposit. The upper drum slightly behind the lower, works the top half of the bed, its picks cutting downwards-in the ideal case it easily deals with the now unsupported mid-seam anhydrite band.

All material cut from the face has to pass between the picks on the two drums which rotating in opposite sense almost mesh together and behave like a two-roll crusher, eliminating oversize lumps which would be unsuitable for the conveyor system. The machines, while all of basically the same design are tailor-made to suit the height of the potash bed to be worked in each panel, the motor power being selected according to the work each drum is expected to do.

Normally the shearer takes a 110 m cut off the face at each traverse, and after completing one cut is slitted back to the other end to start another cut. As the retreat face progresses, the inner wall of the tail drive is drilled and blasted, temporarily widening the passage to accommodate the shearer, as it moves forward into position to make the next cut.

*MDPA–name of a firm.

III.1. After reading the text choose the most suitable title.

-The design of the double-drum shearer.

– Working conditions of the double-drum shearer.

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–A unidirectional machine to work out potash seams.

–The sequence of operations of double-drum shearer work

–The work of a double-drum shearer.

III.2. Try to divide the most complex sentences of the text into 2-3 simple ones.

III.3. Find out sentences containing Absolute Participle Construction.

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UNIT V

Haulage and Hoisting.

Features of Principle Haulage Units.

I

I.1. Find the meanings of the new words and special terms from the dictionary.

I.2. Guess the meanings of the words below minding the similiarity of their stems with those in your native language.

a)horizontal, vertical, functions, normal, distance, maximum, conveyor, zone.

b)identified, grade, primary, equipment, indicated, to elevate,

hydraulic,

pneumatic, complete, variety, predominate rubber, rail, critical, especial, double

I.3. Complete the lines in the way it is in the first one. Pay special attention to column 3 where you must use suffixes “-age”, “-ing”, “-tion” to different words.

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I.4. What is the meaning of “self”? Translate the words below.

Look up into the dictionary to be familiar with a great number of words containing “self”.

I.5. Prefixes in the box are often used to give adjectives a negative meaning. Form the opposites to the words, using the convenient prefixes.

ab-, dis-, il-, im-, un-, ir-, in-

Normal, limited, regular, legal, movable, possible, honest, soluble, true, convenient, similar, usual, stable, flexible.

I.6. Define the meanings of the derivatives.

user using used

use useful useless unused unusable

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