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- 7

 

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1. .

2. .

 

Does not run , is not lower , no air enters / , is not clogged , are not tightened - .

 

3. .

 

1. If the motor heats up you should check a head.

2. The head of the pump should not be lower than provided for.

3. The discharge valve should be throttled to reach the required head.

4. If the pump doesnt reach the required head I will check the direction of rotation.

5. It is not good because if the speed of the motor is lower than the designed one the pump wont reach the required head.

6. I will check the casing if the pump doesnt deliver water.

7. The pump wont deliver water if the suction pipe is closed.

8. The pump has insufficient capacities if it rotates in wrong direction.

9. If the pump rotates in wrong direction it will have insufficient capacities.

10. Yes the vacuum gauge shows that the suction vacuum is high.

11. If the seal rings are worn out I will change them.

12. If the packing gland heats up I will check that the pipe conveying water is not clogged.

13. If packings are tightened too much the packing gland will heat up.

14. Motor, discharge valve, pump casing, suction pipe, vacuum gauge, seal rings, packing gland, packings.

15. It is recommended to rotate the shaft mutually on the coupling.

 

- 1 -

III.

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- 2

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1. .

2. :

 

Chemical energy , heat energy , fuel for consumption , steam bubbles , to pass upward and downward - , natural circulation boiler , water tube boiler , hot combustion gases () , furnace walls , upper drum , lower drum , screen tubes , rows of tubing , boiler tube bank , radiant heat , transfer surface - , convection surface , heat transfer additional surface , saturated steam , superheated steam , heating surface , feed water , boiler feed pipe , air heater , exhaust gases , boiler design .

 

3. .

 

1. Where is heat energy contained? 2. Where is the heated water fed? 3. Where is the feed pipe located? 4. Where is chemical energy contained? 5. Where are steam bubbles formed? where are downcomers located?

 

4. .

 

1. Economizers are used to cool the gases. 2. Furnaces are used to convert chemical energy of fuel into heat energy.3. These tubes are used to connect the upper and lower drums. 4. Burners are used to mix air and fuel for a good combustion. 5. Metal surfaces in boilers are used to transfer heat from the hot gases to the water.

 

5. there is (are) , . ed . .

1. There is water converted into steam. , .

2. There are steam bubbles released from the boiling surface. , .

3. There are voids replenished from the upper portion. , .

4. There are the floor and roof tubes connected through headers and piping to the boiler drums. , .

5. There is one side of the furnace enclosed by screen tubes. , .

6. There is the first row of tubing called the boiler tube bank. , .

 

 

- 3

 

6. .

 

1. How is the tubing surrounding the furnace called? Why so? 2. How many sections is this boiler superheater divided into? 3. What is superheater tubing used for? 4. What is the air heater used for? 5. How is the tubing behind the first row of boiler tubes called? 6. How is that boiler called?

 

7. . in order to .

1. Saturated steam from the boiler upper drum is used to feed the superheating. Saturated steam from the boiler upper drum is used in order to feed the superheating. . , .

2. To obtain more thermal energy from the hot gases additional surface is provided. In order to obtain more thermal energy from the hot gases additional surface is provided. , . , , .

3. The convection heat transfer surface is provided to absorb heat from the hot gases. The convection heat transfer surface is provided in order to absorb heat from the hot gases. . , .

4. To connect the boiler tubes and drums a system of headers and piping is provided. In order to connect the boiler tubes and drums a system of headers and piping is provided. . , .

5. Flames emit radiant heat and the tubes are used to absorb this radiant energy. Flames emit radiant heat and the tubes are used in order to absorb this radiant energy. , . , , .

8. , .

1. No, it doesnt. 2. Yes, it does. 3. No, it doesnt. 4. No, it doesnt. 5.. Yes, it does. 6.. No, it doesnt

9. .

10. .

 

Radiant radiation radiate radiator * . To obtain obtainable unobtainable * . Power powerful powerless powerlessness * . Effective effect ineffectively effectively * . Boiler boiled boiling * . Wide widely width* . Contained container containing * c . To close enclose enclosed disclose* . To use use useful useless usefulness * .

 

 

- 4

 

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I. .

II. 5 .

1. Water tube boilers are widely used on up- to date cargo ships.

2. The additional heating surface provide more thermal energy from hot gases.

3. A system of headers and piping is provided to connect the boiler tubes and drums.

4. Air and fuel are mixed in the burner for combustion.

5. All the tubing surrounding the furnace absorb the radiated energy emitted by flame.

 

III. .

 

1. A part of the steam boiler that burns fuel is the furnace.

2. A device of the boiler that heats the feed water is the economizer.

3. A part of a steam power plant that converts water into steam is the boiler.

4. A device of the steam boiler that heats the steam is the superheater.

5. A device of a steam boiler that heats the steam is the air heater.

6. A device of a steam power plant that supplies the water to the boiler is the feed pump.

7. A part of the steam boiler that protects the furnace walls from high temperatures is the screen.

8. A device of the steam power plant that converts steam into water is the condenser.

 

IV. .

 

For converting , for transferring , for releasing , surrounding gases , boiling surface - , circulating water - .

 

V. .

 

1. The economizer receives feed water at one end. 2. Heated water is fed directly to the feed pump.

2. The gases pass through the boiler tube bank. 4. The tubes are fed with saturated steam.

5. Downcomers are located behind the first row of tubes. 6. The first row of tubes is backed by several more rows of tubing. 7. The furnace is enclosed from three sides. 8. The tubes are connected with piping. 9. Air and fuel are mixed for combustion. 10. The bubbles are released from the surface.

 

VI. .

 

1.In water tube boiler water circulates in tubes which are surrounded by gases from the outside.2. Fuel and air are mixed in the burner for effective combustion. 3. Chemical energy of fuel converts into steam heat energy in the boiler. 4. Circulating water and steam cool tubes and absorb fuel. 5. Burners are located on the front of the boiler. 6. Furnace roof, floor and walls of are screened in some up-to-date boilers. 7. Tubes surrounding the furnace form a convection heat transfer surface.8. Tubes located (backed) behind the first row form a convection heat transfer surface. 9. Superheater heats steam and economizer heats feed water. 10. Air cooler heats the air which is then transferred to the furnace for combustion.

 

- 5

 

VII. .

 

1. The burner mixes fuel and air for combustion.

2. The heat from the hot gases is transferred to a metal surface.

3. Steam bubbles are formed on the inside surface of the boiler.

4. The bubbles pass upward.

5. The voids are replenished by water.

6. We have a natural circulation boiler when no mechanical means are used to cause the steam to pass upward and the water to pass downward.

7. The hot combustion gases should be cooled to the minimum to recover as much of the heat energy in the gases as possible.

8. The circulating steam and water must cool the metal tubing.

9. The furnace is enclosed on three sides: by the roof, by the floor, by a row of screen tubes widely spaced.

10. The tubes are connected through a system of headers and piping to lower and upper drums.

11. Screen tubes are connected to the upper and lower drums.

12. The first row is also spaced widely.

13. The tubing is called radiant heat transfer surface because it absorbs the radiated energy emitted by flames.

14. A few rows of widely spaced screened tubes which form the forth side of the furnace are called the boiler tube bank.

15. Some tubes are considered convection heat transfer surface because they absorb heat from the hot gases by means of convection heat transfer.

16. Additional convection heat transfer surfaces help to obtain more heat from the hot gases.

17. Superheater is used for cooling the gases. no boiling takes place in its tubes. tubes are fed with saturated steam from the top of the upper boiler drum and as the gases are cooled the steam is superheated.

18. No boiling takes place in the economizer, water is only heated.

19. Yes, air heaters recover heat energy from the exhaust gases and heat the air for combustion.

 

VIII. , 6.

 

1. . .

2. .

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- 6

 

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1. .

2. :

 

Combustion space , furnace volume , excess air , refractory fire brick , fuel supply , air supply - , products of combustion , mechanical oil burners , rotary cup atomizers , oil pump , combustion process , fully water cooled furnace , continuous oil fuel supply , to remove products of combustion , flame protection , mixing of oil with air , cone shaped spray , atomizer nozzles , automatically controlled boiler ,viscosity valve - .

 

 

- 7

 

3. Present Perfect Passive .

 

1. Furnace walls have been lined with refractory fire brick. .

2. Mechanical oil burners have been employed for efficient atomization. .

3. Rotary cup atomizers have been designed with automatic ignition system. .

 

4. , must.

 

1. Must the air pass through vanes? 2. Must the mixture of oil fuel and air burn in suspension?

2. Must the furnsce setting withstand high temperatures? 4/ Must the air registers control the air supply?

 

5. Past Indefinite Passive.

 

1. The oil was given a whirling motion in the burner inner chamber. 2. The oil was discharged through a nozzle as a cone-shaped spray. 3. Air for combustion was supplied at a burner.4. the fuel supplied to the atomizers was heated.

 

6. .

 

1. Why are furnace walls lined with insulation? 2. Why are the products of combustion removed?

3. why are burners designed to burn fuel? 4. Why are air registers used to control air supply?

 

7. may.

 

1.Rotary atomizers may be electrically driven. 2. These atomizers may be steam turbine driven. 3. Modern atomizers may be fitted with viscosity valve and automatic ignition system. 4. The burner atomization quality and reability in operation may be high.

 

8. .

9. .

 

Absorb absorption absorber * ; obtain obtainable unobtainable * ; radiate radiation radiant radiator * ; weigh weight weightless * - ; power powerful powerless * ; seam seamless * ; heat heater heated heating.* .

 

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I. .

II. 5 2 ( ).

 

 

- 8

 

1.In boilers the furnace front wall is made of refractory fire brick because it is exposed to high temperature. 2. Air registers control the air supply. 3. A diffuser in the air register is provided for flame protection. 4. A combustion process takes place in the furnace. 5. Mechanical oil burners are of two types: centrifugal atomizers and rotary cup atomizers.

 

III. :

 

1. .

2. .

3. .

4. .

 

IV. .

 

1. The furnace is restricted by surfaces forming combustion space.

2. The oil fuel and air should be burnt in suspension.

3. Thorough mixing of oil fuel and air result in high furnace temperatures.

4. The furnace walls are lined with fire brick and insulation.

5. For the efficient combustion process a certain set of conditions is necessary.

6. Burners are designed for burning fuel.

7. Burners are employed for obtaining efficient atomization.

8. Mechanical atomizing oil burners are classified according to thier method of atomization.

9. The oil is discharged through a nozzle as a cone shaped spray.

 

V. .

 

1.Air for combustion is supplied to the burner. 2. The air is supplied to pass through vanes. 3. The oil fuel and air are mixed at the atomizer nozzle. 4. The oil fuel is supplied to the atomizer. 5. Oil fuel burning equipment consists of atomizer proper and air registers. 6. The diffuser is fitted for the flame protection. 7. Modern atomizers are used with automatically controlled boilers. 8. Modern atomizers are fitted with viscosity valve and automatic ignition system.

 

VI. :

 

1. A furnace must provide a steady burning of fuel. 2. Thorough mixing of fuel with air is very important for a combustion process. 3. Non water cooled furnace walls are lined with fire and insulation brick. 4. A certain set of conditions is necessary for efficient burning of fuel. 5. It is necessary to maintain high temperature in the furnace, to provide continuous air supply to it and to remove the products of combustion. 6. Mechanical oil burners are employed for fuel oil burning. 7. Oil is given a whirling motion and is discharged through the nozzle in the form of a spray in the burner inner chamber. 8. The fuel supplied to atomizers should be heated to decrease its viscosity. 9. Burning equipment consists of atomizer proper and air registers. 10. Rotary cup atomizers are widely used on marine fleet.

 

 

- 9 -

 

VII. .

 

1. A furnace provides steady burning of fuel. 2. The furnace is restricted by surfaces forming combustion space. 3. The mixture of oil fuel and air is burnt in suspension. 4. Furnace walls are lined with fire brick and insulation. 5. The following conditions are necessary to provide the efficient combustion process: maintenance of high furnace temperature, provision of continuous oil fuel and air supply, removing products of combustion. 6. There are many different types of burners. 7. Mechanical atomization burners may be classified as centrifugal atomizers and rotary cup atomizers. 8. Oil fuel burning equipment consists of atomizer proper and air registers. 9. An air register controls the air supply. 10. A diffuser is for the flame protection and better mixing of oil with air. 11. The oil is given a whirling motion in the burner inner chamber. 12. The air for combustion is supplied at the burner. 13. The air passes through vanes to be given a whirling motion. 14. The whirling motion results in thorough mixing of oil fuel and air at the atomizer nozzle. 15. The oil fuel should be heated to decrease its viscosity. 16. Rotary cup atomizers proved reliable in marine practice. 17. They are driven by both steam turbines and electric motors.

 

VIII. :

 

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2. , .

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- 10

 

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