V. Find the equivalents to the following terms.

1. Low-capacity machines a) ил

2. Forced discharge b) централизованное управление

3. Semi-trailer c) машины малой емкости

4. Centralized control d) болотистый

5. Mud e) принудительная разгрузка

6. Boggy f) полуприцеп

VI. Find the equivalents to the following Russian terms.

1. Земляное полотно a) moist clay

2. Отвал b) boggy soil

3. Чернозем с) blade

4. Влажная глина d) earthen structure

5. Заболоченные земли e) black earth

VII. Make up sentences according to the scheme.

A … should be used …B

Помните, что глагол «should» с инфинитивом переводится как «следует».

A B

1. Jacks a) for assembling machines.

2. Tower cranes b) for raising a load to a small height.

3. Hoists c) for lifting materials to be used at construction.

4. Counterweight d) for digging irrigation ditches.

5. Elevating graders e) for removing snow from motor-roads.

6. Bulldozers f) for compensating for the weight of the boom

and part of the weight of the load.

VIII. Translate the following sentences paying attention to the verb “should”.

1. Scrapers should be used on moderately wet sandy soils and loams.

2. Scrapers should not be employed on soils containing large stones.

3. Mechanical feeding devices (питатели) should be used to deliver loose materials smoothly from hoppers to the receiver.

4. Screw conveyors should be used to handle cement, gravel, slag, concrete, wet clay and other loose or viscous materials.

5. Air-tyred and truck-mounted cranes should be provided with outriggers.

6. A semi-trailer elevating grader should be used together with a 100-horse power tractor.

IX. Read and translate the following text.

SCRAPERS

A scraper removes soil slice by slice, transports and places it in an earthen structure, or pushes it to a dump and then levels it. When moving over freshly dug soil the scraper also partially compacts it.

Fig. 5. Design and operation of scrapers:

I – scraper with forced discharge; II – scraper with half-forced discharge;

III – scraper with free discharge; ( a) loading, ( b) transportation, (c) discharge

Scrapers (Fig. 5) are extensively used in road-making, industrial and hydro-technical construction, etc. Scrapers can operate on a wide variety of soils, including black earth, sand and clay. On moist clay and black earth scrapers are not very efficient as the soil sticks to the walls of the bowl and clogs it. They are quite useless on boggy soils as the wheels sink into the mud. Scrapers should be used on moderately wet sandy soils and loams. They should not be used on soils containing large stones.

Scrapers can be classified as follows:

a) by the geometrical capacity of the bowl: 1.5, 3.0, 6.0, 10.0, 15.0, 25 cubic meters;

b) by the mode of locomotion: trailer, semi-trailer and self-propelled;

c) by the method of discharge: with free, half-forced and forced discharge.

Free discharge does not empty the bowl completely of sticky and moist soils. It is employed only in low-capacity machines.

Forced discharge proved to be the most reliable, although it involves a greater consumption of power.

d) by the system of control: scrapers with hydraulic or cable control.

Scrapers with bowls of 6 to 10 cubic meters in capacity were until recently designed in our country mainly with cable control due to the lack of sufficiently powerful hydraulic drives.

Scrapers are used together with tractors. When a scraper has to operate on heavy soil, the pull of one tractor or a two-wheel air-tyred tractor may be insufficient to cut a slice and fill the bowl. In such cases a crawler or a four-wheel air-tyred tractor is used as a pusher. The pulling force of a tractor can be used much better by making two or three scrapers into a train with a centralized control. The scraper controlled from the driver`s cab handles the soil in succession.