Translate the words into Russian.

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Heat-heater-heated-heating; obtain-obtainable-unobtainable; reduce-reduction; viscosity-viscous; provide-provision; pass-passage; vaporize-vapour-vaporization-vaporizer; atomize-atomizer-atomization; revolve-revolution-revolving; rotate-rotation-rotating-rotary.

Choose the proper verb and put it into the correct form. There are more verbs than necessary.

1. The oil … in steam or electric fuel oil heater.

2. Heating … oil viscosity and … it easier to pump, filter and atomize.

3. The heated oil … through the burners where it is ….

4. Mechanical oil burners and steam-assisted ones … to obtain efficient atomization.

5. The furnaces of water tube boilers … with refractory firebrick.

( to heat, to regulate, to pass, to consist of, to reduce, to make, to atomize, to employ, to line, to depend)

6. Translate into English:

1. Топка должна обеспечить устойчивое горение топлива.

2. Стенки топки футерованы слоем огнеупора и покрыты слоем изоляции.

3. Для эффективного сгорания топлива необходим определенный комплекс условий.

4. В топке необходимо поддерживать высокую температуру, постоянно подавать в нее воздух и удалять продукты горения.

5. Топливо следует подогревать для уменьшения его вязкости.

6. Основное преимущество паромеханических форсунок состоит в высоком качестве распыления и широком диапазоне регулирования подачи.

TEXT B

UNIT VI. THE SUPERHEATER

The efficiency of the steam power plant is influenced by the steam conditions, i.e. pressure and temperature. That is why the superheater is an essential part of the modern marine boiler.

Steam is superheated by being heated above the temperature of saturation. Superheaters may be divided into several types:

- the convection type installed in one of the gas passages of the boiler;

- the radiant type installed in the boiler furnace;

- the multi-loop type placed remote from the furnace in the lower part of the uptake.

The convection type superheater usually consists of two headers into which seamless steel tubes are rolled. The tubes are connected to the steam inlet header and to the superheater outlet header. Steam from the boiler circulates through these tubes. Superheater tubes range from 1 to 2 in. in diameter; the temperature rarely exceeds 550°C, as the tensile strength of most metals decreases rapidly after passing 350°C.

With increased evaporation rates and higher superheat temperatures, many modern boilers use multi-loop type superheaters. These superheaters consist of a number of multi-loop tube elements. The steam enters all the tubes together, but makes several passes across the gas stream through each element.

The boiler drums are designed for a certain maximum operating pressure. When the steam pressure gets above the safe minimum, the safety valve should open and steam discharged. So all superheaters must have one or more safety valves.

Vocabulary

superheater, n пароперегреватель

efficiency, n производительность; КПД

steam conditions параметры пара

saturation, n насыщение

convection type superheater конвективный тип пароперегревателя

radiant type superheater радиационный тип пароперегревателя

multi-loop type superheater змеевиковый тип пароперегревателя

remote отдельно

uptake, n дымоход

seamless, adj бесшовный

roll, v вальцевать; прокатывать

inlet header входной коллектор

outlet header выходной (выпускной) коллектор

range, v колебаться в пределах

inch (in.), n дюйм

exceed, v превышать

tensile strength предел прочности

decrease, v уменьшать

evaporation rate скорость или интенсивность испарения;

паропроизводительность

gas stream поток газа

E X E R C I S E S

1. Give English equivalents:

Паросиловая установка, влиять, давление, выше температуры, устанавливать, размещать, соединять с, редко, быстро, использовать, поступать в, рабочее давление, слегка перегретый пар, вспомогательные механизмы, установка/агрегат, при необходимости, потребность в паре, существовать, в случае продувки котла.

2. Complete the statements. Choose the proper word from the list:

Saturation, inlet, tubes, outlet, drums, safety valve, uptake, headers

1. The seamless tubes are rolled into the ….

2. The steam is heated above the temperature of … corresponding to the pressure.

3. If the steam pressure rises above the safe minimum, the … should open.

4. The multi-loop type superheater is installed in the lower part of the ….

5. The tubes are connected to the steam … header and to the superheater … header.

6. The diameter of superheater … varies from 1 to 2 in.

7. The boiler … are designed for a certain maximum working pressure.

3. Answer the questions:

1. Why is a superheater an essential part of the modern marine boiler?

2. What steam is said to be superheated?

3. What types of superheaters do you know?

4. Where are convention type superheaters placed?

5. Where are radiant type superheaters placed?

6. Where are multi-loop type superheaters installed?

7. What does the convection type superheater consist of?

8. Speak about the tube size and operating temperatures.

9. Can you describe multi-loop type superheaters?

10. Why must all superheaters have one or more safety valves?

TEXT C

THE ECONOMIZER

The economizer is a feed-water heater in which flue gases are used as a heating medium. It is used to increase the temperature of feed water before it enters the boiler, by absorbing heat from the flue gases leaving the boiler.

The economizer is interposed between the boiler and stack. The economizer increases boiler efficiency, it lowers the temperature of the exhaust gases and heats up the incoming feed water as it passes through the economizer on its way to the steam drum.

A typical economizer consists of two or more solid-forged mild steel headers, to which series of tubes are connected. The tubes are rolled into the headers. When headers are not employed, return bends, usually connected by flange joints to the straight run of tubing, are used. The steel tubes range from 1 to 2 in. in diameter.

Economizers are parallel or counterflow – parallel when the gases and water flow in the same direction; counterflow when they flow in opposite directions. The counterflow is considered to be more effective, resulting in a greater heat transfer.

Air vents must be provided for the release of air when filling the economizer, or when raising steam. Drain valves fitted to the lower headers enable the economizer to be emptied of water when required.

Efficient soot blowing arrangements must be provided to keep the heat exchange surfaces free from soot. This is important not only in the interests of efficiency, but also to reduce the possibility of an uptake fire starting in sooty deposits.

Vocabulary

flue gases топочные газы

absorb, v поглощать

interpose, v располагать между

stack, n дымовая труба

efficiency, n коэффициент полезного действия, КПД

uptake, n дымоход

solid-forged цельнокованый

header, n коллектор

return bend обратное колено

flange joint фланцевое соединение

counterflow, n противоток; противоточный

drain valve спускной дренажный клапан

soot blowing arrangement сажеобдувочное устройство

deposit, n отложение

E X E R C I S E S

1. Give English equivalents:

Подогреватель питательной воды, топочные газы, греющая среда, поступать в котел, отработавшие газы, проходить через, состоять из, коллектор, с помощью, в одном направлении, в противоположном направлении, приводить к, теплопередача, при необходимости, поверхность теплообмена.

2. Insert prepositions and conjunctions:

1. … the economizer flue gases are used … a heating medium.

2. The economizer is interposed … the boiler and stack.

3. The economizer is placed … the uptakes.

4. Feed water passes … the economizer … its way … the steam drum.

5. The tubes are rolled … the headers.

6. Return bends are usually connected … flange joints … straight run … tubing.

7. The counterflow results … a greater heat transfer.

8. Drain valves enable the economizer to be emptied … water when required.

3. Answer the questions:

1. What is an economizer?

2. What is used as a heating medium in the economizer?

3. What is the economizer used for?

4. Where is the economizer interposed?

5. Does the economizer increase boiler efficiency?

6. What does a typical economizer consist of?

7. What is used when headers are not employed?

8. What is the diameter of the economizer steel tubes?

9. What can occur if the fed temperature falls below 115°C?

10. How are economizers classified according to their gas and water flow?

11. What are parallel and counterflow economizers?

12. Which flow is considered to be the more effective in economizers?

13. What must air vents be provided for?

14. What arrangements must be fitted to keep the heat exchange surfaces free from soot?

4. Translate the phrases containing comparatives and superlatives:

A great heat transfer – a greater heat transfer – the greatest heat transfer;

effective – more effective – the most effective; a large heating surface – a larger heating surface – the largest heating surface.

5. Translate into English:

1. Экономайзер – это подогреватель питательной воды.

2. Экономайзер увеличивает КПД котла.

3. Трубки экономайзера омываются с внешней стороны горячими топочными газами.

4. Возвратные колена подсоединены к прямому трубопроводу с помощью фланцев.

5. Противоток более эффективен, так как приводит к большей отдаче тепла.

6. На экономайзере устанавливают предохранительные клапаны, спускные дренажные клапаны и сажеобдувочные устройства.

UNIT 7

TEXT A

A Procedure for Starting a Boiler

A boiler is one of those machineries that gets the ship going. It is dangerous equipment which generates steam at extremely high pressure, and it is for this reason that proper care should be taken while operating it.

Starting a Boiler

The following steps may not apply to all types of boilers and each boiler requires some additional steps to be followed as for its system design. However, the basic steps remain the same:

1. Ensure that the vent valve on the boiler is open and check there is no pressure in the boiler.

2. Check that the steam stop valve is closed.

3. Check that all the valves for fuel are open, and let the fuel circulate through the system until it comes to the temperature required by the manufacturer recommendation.

4. Check and open the feed water valves to the boiler and fill the water inside the boiler drum to just above the low water level. This is done because it is not possible to start the boiler below the low water level due to safety feature which prevent boiler from starting. Also, the level is not filled much because if filled too much, the water inside the boiler might expand and over pressurize the boiler.

5. Start the boiler in automatic mode. The burner fan will start the purging cycle which will remove any gases present in the furnace by forcing it out through the funnel.

6. After the pre-set purge time the pilot burner will ignite.

7. The main burner which is supplied by heavy oil catches fire with the help of pilot burner.

8. Check the combustion chamber from the sight glass to ensure the burner has lit and the flame is satisfactory.

9. Keep a close eye on the water level as the pressure increases and open the feed water when the level of water inside the gauge glass is stable.

10. Close the vent valve after the steam starts coming outside.

11. Open the steam stop valve.

12. Once the working steam pressure is reached, blow down the gauge glass and check for the alarms.

E x e r c I s e s

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