3. Scrapers are used together with tractors.
4. Scrapers are controlled from the driver`s cab.
XVI. Answer the following questions.
1. What is a scraper used for ?
2. Where are scrapers extensively used?
3. On what soils can scrapers operate?
4. How are scrapers classified?
5. On what soils are scrapers quite useless?
6. What can you say about free discharge and forced discharge?
7. In what cases is a four-wheel air-tyred tractor used as a pusher?
8. In what cases are scrapers used together with tractors?
XVII. Translate the following sentences into English.
1. Известно, что скреперы предназначены для послойной разработки грунта.
2.При движении по свежеотсыпанному слою грунта скреперы частично уплотняют его.
3. Скреперы не могут работать на заболоченных землях вследствие того, что колеса вязнут в грунте.
4. Нельзя применять скреперы на грунтах, содержащих крупные камни.
5. Скреперы классифицируются по геометрической емкости ковша, по способу передвижения, по способу разгрузки и по системе управления.
6. Самой надежной, хотя и несколько энергоемкой, является принудительная разгрузка.
7. Свободная разгрузка применяется в машинах малой емкости.
Scrapers
Scrapers towed (буксировать) by crawler tractors have a very low traveling speed. The working cycle of a scraper takes 5 – 20 minutes. They can also be towed by two-wheel air-tyred tractors. The tractor and the scraper have two wheels each. The tractor and the scraper are linked by means of a pivot. So they can turn in two planes. The tractor can turn through 90 deg. to either side and through + or – 15 degrees vertically.
Scrapers have unique abilities for cutting, filling, pulverizing and grading. Scrapers handle areas restricted to rubber-tyred equipment. However (однако), scrapers lose (терять) traction on wet surfaces and cannot load materials that are too rocky (твердый) Because of their speed elevating graders outperform (превосходить) crawlers and are more economical on longer hauls (перевозки).
The all-purpose scraper can pulverize top soil, bring low spots to grade and finish grade projects sides. In road building the elevating scraper acts as a clean haul earthmover. Scrapers load up skin excess (излишки отбросов) that graders push to the side and haul it to low spots.
Situation: You are preparing for the examination in English and discuss the theme “scrapers” with your friend.
A. Let`s discuss the theme “scrapers”.
B. I don`t mind. As far as I know scrapers remove soil slice by slice and transport it to an earthern structure.
A. Yes, they also may push soil to a dump and then level it.
B. What do you think, can they compact soil?
A. Yes, they partially compact it. Scrapers can operate on a wide variety of soils, including black earth, sand and clay.
B. Can they operate on soils containing large stones?
A. No, as far as I remember, they should not be used on soils containing large stones.
B. I see, thank you.
A. Not at all.
УРОК 9 LESSON NINE
Фонетика: Повторение чтения буквосочетаний «OW» и «CH».
Грамматика: Перевод глаголов «to be», «to have» в модальном значении.
Complex Subject. (Повторение).
Тема: Автогрейдеры. Power Graders.
E X E R C I S E S
[Pu] - low, lower, tow, own, snow, follow, window.
[au] - power, powerful, tower, now.
[k] - mechanical, character, characteristic, chemical.
Example: necessary – necessity – необходимый – необходимость;
responsible – responsibility – ответственный – ответственность.
Active, possible, reliable, manoeuvrable, capable, stable, universal.
1.Power grader [`pauq`greidq] – автогрейдер
2. Scarifier [s`kxrifaiq] n – кирковщик
3. Side ditch [`said`diC] – кювет
4. Shape [Seip] v - придавать форму, профилировать
5. Towed [`tPud] a – прицепной
6. Gradient [`greidiqnt] n – уклон, скат
7. Profile [`prPufail] a – вертикальный
8. Possibility [,pOsi`biliti] n - возможность
9. Carry out [`kxri`aut] – выполнять
10. Lay [lei] v –прокладывать
11. Elevation [eli`veiSn] n –высота
12. Zero elevation [`ziqrPu eli`veiSn] – нулевая отметка
13. Volume [`vOljHm] n – объем
14. Set [set] v – устанавливать
15. Angle [`xNgl] – угол
16. Perform [pq`fLm] – выполнять
17. Repair [ri`pFq] n – ремонт
v – ремонтировать
18. Medium [`mJdiqm] a – средний
19. Plough [ plau] n - плуг
1. Gradient a) боковые откосы насыпи
2. Elevation b) возможность
3. Side ditch c) уклон
4. Possibility d) кювет
5. Towed grader e) высота
6. Sides of fills f) прицепной грейдер
1. Мощные автогрейдеры a) running gear
2. Земляное полотно b) small repair
3. Производительность с) powerful power graders
4. Ходовое оборудование d) capacity
5. Мелкий ремонт e) earth bed
Помните, что глаголы «to be» и «to have» переводятся «долженствованием», если после них стоит инфинитив глагола с «to».
1. Heavy graders are used when large volumes of soil have to be handled.
2. A powerful grader is a highly manoeuvrable machine.
3. The principal parts of an elevating grader are the main frame, a vertical frame, a share arm and a conveyor, etc.
4. When a scraper has to operate on heavy soil, the pull of one tractor may be insufficient to cut a slice and fill the bowl.
5. A bulldozer is a pendant attachment mounted on crawler and wheel tractors.
6. The weight of the load is to be estimated (оценивать) beforehand.
7. Cranes have to be provided with outriggers.
8. Bearing surface of a crane has to be increased by outriggers.
Example: We know that winches are widely used in construction.
Winches are known to be widely used in construction.
We know winches to be widely used in construction.
1. We know that towed graders are less manoeuvrable and have a smaller capacity.
2. It is considered that towed graders do not have great possibilities.
3. We believe that elevating graders are used for digging irrigation ditches.
4. We know that scrapers are used with tractors.
5. It is proved that forced discharge is the most reliable.
6. It is proved that forced discharge involves a greater consumption of power.
7. We know that a hoist is a simple suspension-type small-size mechanism.
POWER GRADERS
Power and towed graders are used in road construction to excavate side ditches, shape the surfaces and sides of fills and cuts and give them the required gradient. It should be noted that powerful self-propelled graders can also be used for laying earth beds, for building platforms and making profile cuts and banks. In winter-time power graders are used to clean roads of compacted snow.
A powerful grader is a highly manoeuvrable machine and its blade can be set at various angles both horizontally and vertically or brought out sideways.
Towed graders which perform the same functions as self-powered machines have no engine or transmission of their own and are driven by crawler tractors. Towed graders are known to be much less manoeuvrable and have a smaller capacity. This type of machine is not considered to have great possibilities and is not being developed. The basic operating members of a grader are a blade and a scarifier.
Power graders can be classified as follows:
a) by weight: light ( up to 9 tons), medium (up to 10-12 tons), heavy (13-15 tons), and very heavy (17-23 tons);
b) by the design of running gear: four wheelers (with one or two driving axles) and six-wheelers (with two or three driving axles;
c) by the type of control used: with the operating member, with mechanical (reduction gear) or hydraulic control.
Light power graders are employed to maintain and carry out repair on roads and to construct earth beds at zero elevation.
Medium graders are used to lay earth beds at small elevations and for repair jobs.
Heavy and very heavy graders are used when large volumes of soil have to be handled or when the soil is difficult to move.