Water supply schemes

1. Mind the pronunciation of the words below.

scheme [skJm], urban [Wbqn], asbestos [xz'bestOs], cement [sI'ment], abrasion [q'breIZn], aspect ['xspekt], route [rHt], modelling ['mOdqlIN], strategic [strq'ti:GIk], identify [aI'dentIfaI], diameter [daI'xmItq].

2. Remember the following words and word combinations.

distribution – распределение

intake – водоприемное сооружение, водоприемник

transmission pipeline – магистральный трубопровод

water treatment works – водоочистные сооружения

forwarding pump station – перекачивающая станция

service reservoir – рабочий резервуар

convey – транспортировать, передавать

potable water – питьевая вода

(pressure) head – напор

prestressed concrete – предварительно напряженный бетон

reinforced concrete – армированный бетон

ductile iron – ковкое (мягкое) железо

assess – оценивать

performance (of a material) – характеристика, работа

durability – прочность, долговечность

resistance – прочность, стойкость

(water) main – магистральный водопровод

2.Watch out!

scheme – система, не только схема

master plan – генеральный план

identify – распознавать, не только идентифицировать

3. Text.

Many water supply schemes worldwide include river intakes and pump stations, raw water transmission pipelines, water treatment works, forwarding pump stations, transmission mains and service reservoirs. Schemes include water supply to both major urban areas and small rural communities.

Transmission pipelines are designed to convey a range of liquids including potable water, seawater, sewage and irrigation water, together with pipelines for the oil and gas industry. They are designed with diameters ranging from 75mm to 4m and pressures ranging from low pressure gravity pipelines to high pressure pipelines rated at 1,500m head.

Pipeline designers should be familiar with a wide range of materials including prestressed concrete; reinforced concrete; steel; ductile iron; asbestos cement; glass reinforced plastic; PVC-U; MDPE and HDPE.

In selecting the most appropriate pipe material for a given scheme they should consider the ground conditions along the pipeline route and assess the performance of the pipe material in terms of durability, resistance to chemical attack, corrosion and abrasion. The above aspects are considered in conjunction with the cost of procurement and installation to provide the most economical solution.

Comprehensive knowledge of the way a distribution system will operate can be gained through modelling and is essential to the efficient design of a distribution system. Modelling can be used at all stages of the asset cycle. As a planning tool, it can be used as the basis for master plans and strategic studies. As a design tool, it can be used for the sizing of mains and the location of reservoirs and pumping stations. As an operational tool, it can be used to identify constraints in the system and poor operational practices; and to monitor and control system operations.

Notes:

1. ranging from … to – от … до

2. PVC-U – поливинилхлоридуретан

3. MDPE – полиэтилен средней плотности

4. HDPE – полиэтилен высокой плотности

5. in terms of – относительно, в отношении

6. at all stages of the asset cycle – зд. на всех стадиях строительства системы водоснабжения

7. constraints – зд. сбои

4. Give synonyms.

select, appropriate, water supply scheme, run water, rural, potable water, be familiar with, in conjunction with, operate, essential, performance.

5. Give English equivalents of the word combinations below.

генеральный план, во всем мире, насосная станция, трубопровод низкого/высокого давления, наиболее подходящий материал, стойкость к коррозии, экономичное решение, обнаружить сбои, плохая работа, доставка и установка, водоснабжение городских районов, условия грунта.

6. Answer the questions.

1. What are transmission pipelines designed for? 2. What should pipeline designers take into consideration when selecting a pipe material? 3. What part does modelling play in designing a pipeline?

7. Translate the text in the written form using a dictionary.

Water suppliers devote substantial time and resources each year for the maintenance and repair of the water distribution system, as well as for the construction of new facilities required to accommodate system growth. However, because of the age of the water distribution system, we believe it is important to provide funding to rebuild deteriorated sections of the water system rather than continue to incur the expense of repair.

Each year a number of sections of water distribution mains are found to be in poor condition and in need of repair. These water mains have deteriorated due to age, the use of substandard materials in the past, soil conditions which have caused the mains to corrode, or a combination of these factors.

When water main breaks occur, valves are used to turn off the water so that repairs can be made. If the valves closest to the main break are inoperable, other valves must be closed, necessitating the interruption of water service to additional customers. To avoid this the distribution system should be surveyed to determine where older valves should be replaced and where the installation of additional valves would enhance system control.

Дата добавления: 2015-07-14