Dredging ships. Практикум для СПО

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UNIT I

DREDGING SHIPS

I. Pre-reading task

Exercise 1. Study the following words and word combinations.

dredger — земснаряд silt — тина

pole — багор

reclaim — восстановить, осушить waste area — пустошь

soil — грунт dyke — плотина dam — дамба lock — шлюз bucket — черпак

suction dredger — землесос cutter — фреза

cutter suction dredger — землесосный снаряд для скальных пород washing-out-pipe — гидроразмывная труба

nozzle — сопло

suction pipe — сосуновая труба hopper — грунтовой трюм mud barge — шаланда

II. Reading activities

Exercise 2. Read the text.

Text

[…]

A dredger is a vessel specially designed to remove part of seabed in order to produce a greater depth of water.

[…]

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The first dredgers were invented in Denmark in the XII-th century. The Dutch at that early period cleared their canals of silt with a pole to which was attached a bag held open by a steel ring. The apparatus, operated from the side of a stationary barge, was dragged along the bottom and then emptied into the barge. In the XVII-th and XVIII-th centuries numerous dredging projects were carried out in France, England, Italy and Russia. Dutchmen worked on the reclamation of waste areas along the banks of the Dnieper and Volga rivers, and remained there until the start of the First World War.

[…]

What sort of work do dredgers carry out? Broadly speaking, there are five main categories:

-excavating and maintaining the depth of navigable waters;

-reclaiming soil for use as fill;

-constructing or improving irrigation and drainage systems;

-building dykes, dams and other defenses against water;

-Infrastructural work such as locks, bridges and port facilities.

[…]

There are several kinds dredgers for various dredging operations. They are: hydromonitors, bucket dredgers, suction dredgers, cutter suction dredgers and some others.

[…]

The most simple dredging device is a hydromonitor. It washes out the bottom by means of water sprayed under pressure through the nozzles of the washing-out - pipe.

[…]

A suction dredger is a ship which has a suction pipe to suck the mixture of water and ground. To carry out dredging operations on hard bottom suction dredgers are provided with cutters. Such dredgers are called cutter-suction dredgers.

[…]

Bucket dredgers work on hard and rocky bottom. Their buckets are usually made of high grade steel. The bucket line is mounted on a ladder. The dredged material is elevated from the sea bottom by rotating the bucket line. The buckets are discharged into the hopper or into the mud barge by means of conveyers.

[…]

The modern dredging ships have up-to-date automating dredging equipment.

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Exercise 3. Think of a title for each paragraph and put them down in the appropriate boxes.

III. Comprehension check

Exercise 4. Answer the questions.

1.What is a dredger?

2.When and where were the first dredgers invented?

3.What is the range of tasks for dredgers?

4.What kinds of dredgers do you know?

5.How does a hydromonitor work?

6.What dredgers are used to carry out dredging operations on heavy bottom?

7.What material are the buckets made of?

8.What equipment do modern dredgers have?

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UNIT II

SUCTION DREDGER

I. Pre-reading task

Exercise 1. Study the following words and word combinations.

centrifugal pump — центробежный насос

axial-flow pump — насос с осевым движением потока tool — инструмент

spoil — пульпа

suction head — грунтоприёмник dredging pump — грунтовой насос force piping — силовой трубопровод

II. Reading activities

Exercise 2. Read the text.

Text

This is often the most commonly used form of dredging.

A suction dredger is a dredger extracting the soil by use of a centrifugal or axial- flow dredge pump. A suction dredger has a suction pipe to suck the mixture of water and ground. A plain suction dredger has no tool at the end of the suction pipe to

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disturb the material. The spoil enters the suction head, passes through the suction pipe and then enters the dredging pump. The pump driven by the main engine delivers the spoil into the ship’s force piping from where it passes to the floating piping rested on floating pontoons. If it is necessary to deliver the spoil ashore, the shore–piping is connected to the floating piping.

To carry out operations on hard bottom suction dredgers are provided with cutters.

Exercise 3. Fill in the gaps.

1.A suction dredger is a dredger extracting the … by use of a … or … … dredge pump.

2.The mixture enters the … …, passes through the … … and then enters the

……

3.The pump delivers the … into the …

4.The shore-piping is connected to…

5.To carry out operations on hard bottom suction dredgers are provided with …

III. Comprehension check

Exercise 4. Answer the questions.

1.What is a suction dredger?

2.What types of pumps are used on suction dredgers?

3.How does a suction dredger work?

4.What are the suction dredgers provided with to work on hard bottom?

IV. Grammar check

Exercise 5. Match the sentences and their English equivalents.

1.Насос, приводимый в движение главным двигателем, доставляет грунт

вгрунтовой трюм, шаланду или на берег.

2.Насос приводится в движение главным двигателем, чтобы доставлять грунт в грунтовой трюм, в шаланду или на берег.

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3.Землесосы снабжаются фрезами для производства работ на твёрдом

грунте.

4.Землесосы, снабжённые фрезами, производят работы на твёрдом грунте.

a)Suction dredgers are provided with cutters to carry out operations on hard

bottom.

b)Suction dredgers provided with cutters carry out operations on hard bottom.

c)The pump is driven by the main engine to deliver the spoil into the hopper, to the mud barge or ashore.

d)The pump driven by the main engine delivers the spoil into the hopper, to the mud barge or ashore.

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