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Ballast Regulators

General Purpose Cranes

Jarvis Rail’s General Purpose Crane is used to support all railway work and is capable of lifting up to 12 tons. It can be used in tandem with another crane for lifting track panels and is particularly useful for switch and crossing work. This machine must always be loco hauled to site. Jarvis Rail’s GP cranes were

manufactured by Plasser and Theurer and Cowan and Sheldon.

1)What operations do ballast cleaners perform?

2)What is a twin jib track relaying machine?

3)What kinds of modern ballast regulators do you know?

4)How do general purpose cranes work?

5)What is a single line gantry?

Optional tasks

1. Look carefully through the tables describing the machines. Try to explain their differences and similarities.

Example: Ballast cleaners and ballast regulators are both self propelled but they differ in other technical features. Ballast cleaners travel only at speed of 56 kilometres per hour whereas ballast regulators develop the speed of 72 km/h.

2. Fill in the chart with the ticks and give reasons for your decision.

3.Check the new words in the dictionary. Try to explain the difference between the machines mentioned above. Use the new words.

4.Check your knowledge.

a. Choose less formal synonym to the following word:

The rate of this heavy duty machine depends on site and ground conditions.

1)place

2)spot

3)space

4)seat

b. Insert the necessary preposition:

They can lift out heavy track panels and replace them … new prefabricated panels while working from an adjacent line.

1)in

2)with

3)on

4)to

c.Give the right spelling of a construction machine which lifts out heavy panels:

1)crain

2)creyn

3)crane

4)creine

d.Choose the right variant:

Jarvis Rail’s General Purpose Crane is used to support all railway work and is capable … lifting up to 12 tons.

1)at

2)before

3)by

4)of

e. What is the English for ‘подвижной портальный кран’?

1)gantry

2)crane

3)tap

5.Now you are a mechanical engineer. You’ve just graduated from the University and your new job involves construction machines maintenance. There are a number of various machines in your company but you are responsible for only one. Give information about:

a)the type of this machine

b)where the worksite is situated

c)the age of the machine and its durability

d)its compulsory and optional functions

e)how many hours a day it can run non-stop

f)when its last technical examination took place

g)what you like and what you dislike about your machine.

Test 13

I. Match the terms with their definitions.

2. track prefabricated panels b. US — an open railway track for carrying goods such as coal

II. Match Russian and English words and phrases.

III. Look carefully through the tables in Unit 13 and decide if the sentences are true (T) or false (F).

a)Ballast cleaners can be used not only in plain line tracks.

b)Track relaying machines can replace new panels while working on one and the same line.

c)Ballast regulators make track tamping more difficult.

d)General purpose cranes can be used in tandem with another cranes.

e)Single line gantries can be used only on double track sections of railway.

IV. Choose the appropriate word in B and put it into the gap in A.

1.It can be used not only on _____________ but also a. travel switch and crossings, using an extended cutting bar.

2.A ballast regulator ploughs and sweeps __________ b. ballast after installation to tidy the track and facilitate tamping.

V. Make up sentences choosing the correct information to characterize road construction machines.

Road construction machines perform well as they

a)are designed specifically for track-laying duties

b)carry millions of passengers

c)are intended to perform alignment of railroad track, lining of track and tamping of ballast

d)accept imposed dynamic and static loads as cars, locomotives and trains

e)unclip the old rail and shift it out to the side, take out the old sleepers and dispose of them in wagons, retrieve new sleepers and drop them in position, and finally clip in the new rail

f)can store excess ballast and drop it in areas where ballast is depleted

g) achieve high speed and great transport capacity.

Unit 14

You are going to read a text which consists of nine paragraphs. First read the opening of each paragraph.

1)Earth digging operations require…

2)It is impossible to start on a construction job without a good deal of preliminary levelling the site. To carry out this work one must employ the earth-moving equipment...

3)Plant for site preparation and excavation can be divided into four classes…

4)Bulldozers of different types belong to the first class of machines…

5)A scraper which belongs to the second class of earth moving machines is simply a large box with an open mouth dragged along the surface of the ground until it is full.

6)The universal excavator is an earth-moving machine that can be equipped with different attachments known under the following names…

7)Some decades ago only rope-controlled excavators were in use.

8)With the wheeled excavator, which is considerably lighter than the crawler mounted one, means to provide additional stability are incorporated. Before starting digging operation outrigger arms provides for …

9)A recent model incorporates a telescopic dipper arm: when extended it can dig deeper and has a greater discharge height and when retracted it produces its greatest digging force at the bucket…

a.Guess how the paragraphs will continue.

b.What do you think the text is about?

1. Read the text and match the openings above to the paragraphs. Example: 6-a)

a)… First, machines which plane off a thin layer of soil and push it in front of them. Second, machines which plane off a thin layer of soil at the same time picking it up and carrying it where required. Third, machines which dig out soil by some form of a bucket and load it for transportation into separate vehicles. Fourth, machines designed especially for trenching by means of a number of buckets mounted either on a continuous chain or on a wheel.

b)… The crawler-mounted excavator has two other advantages over its rope-operated counterpart: with separate hydraulic motors for each track it is possible to put one track in reverse while the other is driven forward so that the machine can be turned within its own length and the boom can be of the adjustable radius type, so that the reach, digging depth and discharge height can be quickly varied to suit the job.

c)… leveling the machine on sloping ground so that trenches with vertical sides can be cut perpendicular to the direction of the slope. In some models the revolving superstructure of the machine can be moved transversely in special guides so that a trench can be dug parallel and close to a wall or some other obstruction this movement being carried out hydraulically too.

d)… A bulldozer represents by itself an earth-moving machine which carries out its work with the help of a blade mounted on a tractor of either crawler or wheel type.

e)… the employment of a great plant of powerful earth-moving machines, the excavators being the most important of them.

f)… It has a cutting edge that digs. There is a considerable variety of scrapers from small units to huge ones made to accommodate 30 cubic yards of soil and to absorb the power of two tractors while at work.

g)… shovel, drag line, backacter or backhoe, grab or clamshell, crane. Conversion from one type to another is a comparatively easy operation.

h)… Now hydraulically operated excavators are in wide use, especially hydraulic backhoes. In hydraulically operated backhoes hydraulic rams are used instead of ropes and winches to operate the boom and the dipper arm. The hydraulic system makes it possible to pivot the bucket on the dipper arm. This movement provided by an additional ram on the dipper arm gives the operator a means for selecting the proper angle of cutting for the bucket both at the start of the digging stroke and during the stroke to obtain optimum digging performance.

i)… Site preparation and excavation are the most fully mechanized of all the operations in building construction. Most excavating machinery is heavy and slow-moving and must be carried from site to site on special transporters. It is clear that the use of expensive mechanical plant requires careful planning and efficient site organization if full advantage is to be taken of its high rate of production.

2. Read and remember the meanings of the words.

3. What would be the best title for this text?

•Earth-moving machinery

•Excavators

•Construction and road machines

•Technology of machine construction

4. Complete these sentences with the words and word combinations from the text.

1)There is a considerable variety of scrapers ________________.

2)Some decades ago only rope-controlled excavators ______________.

3)A bulldozer represents __________________.

4)Independent movement of the outrigger arms provides for _____________.

5)Site preparation and excavation are ______________________.

6)In hydraulically operated backhoes hydraulic rams are __________.

5. Combine the incomplete sentences in group A with their endings in group B.

6.In some hydraulically operated f. … the machine can turn within its own excavators the revolving superstructure length.

…

7.With extended telescopic boom … g. … can be moved perpendicularly to

6. Match the words with the same meanings.

7. Read the Russian text and render it in English.

На универсальных гидравлических экскаваторах наиболее часто применяют обратную и прямую лопаты, грейфер, рыхлители, гидромолот, погрузчик и сменные рабочие органы для различных работ.

При работе обратной лопатой улучшается наполнение ковша и точность выгрузки в результате его поворота относительно рукояти, появляется возможность широкого применения удлиненных стрел и рукоятей, а также профильных ковшей для рытья и очистки каналов, кюветов.

Прямую лопату гидравлических экскаваторов широко применяют на экскаваторах 4-й размерной группы, а также машинах большей мощности. Основными составными частями ее являются стрела, рукоять, ковш и гидроцилиндры — подъема стрелы и поворота рукояти.

На экскаваторах ЭО-4124А устанавливают как поворотный, так и неповоротный ковши. Экскаватор с погрузочным оборудованием (погрузчиком) предназначен для разработки грунтов и погрузки сыпучих и дробленых материалов выше уровня стоянки машины. Как и у прямой лопаты, погрузчик работает движением ковша от себя (от машины в сторону забоя или отвала материалов). Вместимость ковша погрузочного оборудования обычно в 1,5…2 раза больше вместимости копающего ковша прямой лопаты, что позволяет

существенно повышать производительность экскаватора.

На экскаваторах с гидравлическим приводом устанавливают жестко подвешенные грейферы. Основное преимущество жестко подвешенного грейфера по сравнению с канатным заключается в том, что им можно создать необходимое давление на грунт при врезании, т.е. независимо от массы грейфера эффективно разрабатывать плотные грунты.

Оборудование грейфера с составной стрелой состоит из рукояти, используемой от обратной лопаты, подвески, механизма поворота ковша и гидроцилиндра для замыкания и открывания челюстей ковша.

Экскаватор с рабочим оборудованием однозубого рыхлителя предназначен для разрушения мерзлых грунтов, разработки трещиноватых скальных пород, взламывания асфальтового покрытия, выемки бордюрного камня, корчевания пней.

Сменное рабочее оборудование захватно-клещевого типа предназначено для рыхления мерзлых грунтов, разборки старых зданий, взламывания и погрузки асфальтобетонных покрытий, снятия и укладки дорожных плит, труб, установки колодцев. Поставляют его отдельными комплектами в двух исполнениях (с одно- и трехзубым рыхлителемзахватом) и устанавливают вместо ковша и рукояти обратной лопаты, составную стрелу из двух частей оставляют.

Use the words and phrases given below: