Поставьте следующие предложения во множественном числе.

1. My best friend is a boy.
2. This is a mouse.
3. That is a good pen.

3. Вставьте some, any или по и переведите.

1. Are there … English textbooks on the desk? Yes, there are.
2. Have you got... time to spare? I'd like to ask you... questions.
3. There is … butter on the plate.

4. Раскройте скобки, употребляя тре­бующуюся форму прилагательного.

1. Today the weather is (cold) than it was yesterday.
2. My friend’s car is not so (new) as my car.
3. (Long) day has an end.

5. Прочитайте и переведите текст устно. Перепишите и письменно переведите рой абзац текста. Ответьте на вопросы.

CENTRIFUGAL GOVERNORS

1. Most engines in industrial use have to run at a constant speed, irrespective of the load they carry. In order to keep the engine speed within the limits which it was designed for, a device which is known as a governor is incorporated in the engine. Its function is to control the running speed under all conditions of load.

2. The simplest form of governor consists of two balls which are attached to a vertical shaft by means of arms. These balls act as weights. While they are stationary, they are acted upon only by gravity. The vertical shaft is geared to the engine, and rotates with it. When the engine starts, it causes the shaft to rotate, and this forces the rotating balls outwards under the influence of centrifugal force. This movement of the balls at the end of their arms is trans­mitted to a sleeve which is free to slide up and down the shaft. As the engine increases speed, it rotates the shaft more quickly, and the weights rise further against the force of gravity. The sleeve also rises up the shaft, and when it rises beyond a certain point, it operates a throttle valve lever, and so reduces the flow of steam. The engine speed will then decrease, and as the sleeve slides down, it opens the throttle valve again. Governors which are required to work at very high engine speeds are normally weight-loaded. A weight is attached to the sleeve, and prevents the sleeve from rising too far.

3. Both the simple and weight-loaded governors depend on gravity and must therefore be kept in a vertical position. This is often a disadvantage overcome by the use of a spring instead of a weight. The spring performs the same function as the weight, and keeps the sleeve depressed. It can be mounted in any position. By making simple adjustments to the loading on the spring, the governor speed can easily be altered. Ball bearings at the pivots and at the top of the spindle serve to reduce wear and friction.

Vocabulary

1. centrifugal governor – центробежный регулятор

2. to incorporate - вмонтировать

3. arm - рычаг

4. weight - груз

5. to gear - присоединять

6. sleeve - втулка

7. throttle valve - дроссельный к лап

8. weight-loaded - нагружен грузом (на рычаге)

9. spring - пружина

10. pivot опора

Ответьте на вопрос: What do the weight-loaded governors depend on?

 

 

Вариант 5

 

1. Вставьте артикль, где необходимо:

1. She has two children.

1. On … table I have … book, two … pencils and … pen.
2. Will you have … cup of … tea?

2. Поставьте следующие предложения во множественном числе:

1. She has a nice book.
2. That is a coat..
3. This girl is a singer.

3. Вставьте some, any или по и переведите.

1. There is … cheese on the table, but there is … milk.
2. Is there…paper on your table?
3. There are … old houses in our street.

4. Раскройте скобки, употребляя тре­бующуюся форму прилагательного.

1. It was (bad) cold I ever had.
2. Apples are (cheap) than oranges.
3. (short) month of the year is February..

 

5. Прочитайте и переведите текст устно. Перепишите и письменно переведите второй и третий абзацы текста. Ответьте на вопросы.

CRANES

1. Cranes are of many different kinds, depending on the purpose for which they are intended and on the magnitude of the loads to be handled. They may be mobile or stationary. The load is picked up by means of such attachments as hooks or tongs (for individual loads) or by means of buckets, skips or grabs (for bulk materials). A special lifting attachment, used mainly for the handling of scrap iron, is the lifting magnet. These attachments are usually suspended from wire ropes which pass round various pulley systems and are wound on hoist drums which are driven by electric motors.

2. A major distinction can be made between bridge cranes and jib cranes. A crane of the bridge type has a trolley, or crab, which travels along a track and carries the winch that lifts the load. The commonest form of bridge crane is the overhead traveling crane used in factories, workshops, etc. Such a crane usually consists of a "bridge", comprising two girders, each end of which is mounted on a truck which travels on an overhead track along the length of the building. The crab can travel to and fro on a transverse track installed on these girders. The combined movements of the crab and of the crane as a whole enable the lifting hook to be brought into position at any desired point in the building.

3. A jib crane has an arm — called the jib or boom—which can usually perform a "slewing" motion, i.e. rotate horizontally about a vertical pivot mounted in the substructure of the crane. In addition, the jib is often able to perform a "luffing" motion, i.e. it can be raised or lowered by varying its angle of inclination. The combination of these two motions enables the hook to be brought into position at any desired point within a certain radius. A type of jib crane used on construction sites for tall buildings is the tower crane.

4. Every crane has a certain lifting capacity, ranging from a few tons to many hundreds of tons, depending on the type of crane and the purpose for which it is intended. In jib cranes the capacity usually varies with the radius, which depends on the slope of the jib. When the latter is raised to a steep slope, the crane can carry a heavier load than when the jib is lowered to its farthest extent and the radius is large. This difference in lifting capacity at differ­ent radii is determined by the stability of the crane, i. e. its safety against overturning. The weight of the load (suspended from the jib) multiplied by the radius constitutes the overturning moment. The latter is balanced by a heavy counterweight.

5. Besides hooks, a variety of lifting and handling devices can be attached to cranes. An important device for picking up bulk mate­rials such as coal, ore, etc., is the grab. It can open and close to pick up the load and discharge it. These movements are produced by working the holding and closing ropes.

Vocabulary

1. crane - кран

2. load - нагрузка

3. mobile - передвижной

4. stationary - неподвижный

5. hook - крюк

6. tongs - клещи

7. bucket - ковш

8. grab - грейфер, ковш

9. lifting magnet - подъемный магнит

10. attachment - дополнительное приспособление

11. scrap iron - лом

12. ropes - тросы

13. bridge crane - мостовой кран

14. jib crane - кран-укосина, кран на колонке

15. crab - кошка (крана)

16. trolley - кошка (крана)

17. traveling crane - мостовой кран, пере­движной кран

18. boom - стрела

19. slewing - поворотный, вращающийся

20. luffing - изменение вылета стрелы; изме­нение наклона укосины

21. lifting capacity - грузоподъемность, подъ­емная сила

22. slope - наклон

23. counterweight - противовес

24. handling devices - устройства для подъ­ема грузов

25. working - зд. приведение в действие

Ответьте на вопрос: What is the load picked up with?

 

Вариант 6

1. Вставьте артикль, где необходимо:

1. This is my … table. On … table there is … flower.
2. I have no … pencil.
3. My … brother is not at … home.

2. Поставьте следующие предложения во множественном числе:

1. It is a long pencil.
2. Mary has a dog.
3. This is a sheep.

3. Вставьте some, any или по и переведите.

1. There is … ham on the plate.
2. There is … tea in the cup: the cup is empty.
3. There are … people in the garden because it is cold.

4. Раскройте скобки, употребляя тре­бующуюся форму прилагательного.

1. Winter is (cold) season of the year.
2. These sweets are (nice) than the sweets in that box.
3. The Baltic Sea is not so (warm) as the Black Sea.

5. Прочитайте и устно переведите текст. Перепишите и письменно переведите последний абзац текста. Ответьте на вопросы для самоконтроля

LIQUID FLOW AND METERING

1. The behavior of a fluid flowing through a pipe is affected by a number of factors, including the viscosity of the fluid and the speed at which it is pumped. Below a certain critical speed, the flow is smooth, but when the speed is increased beyond this value, the fluid becomes unstable, eddies being formed which give rise to turbulence and loss of kinetic energy. The speed at which this occurs varies both with the internal diameter of the pipe and with its surface characteristics. Small roughness on the pipe walls do not materially affect the flow. But heavy roughness increases the tur­bulence with more of the kinetic energy of the fluid being dissipat­ed as heat.

2. Liquids flowing through pipes are subject to loss of head due to frictional forces at the surface of the pipe.

3. An accurate estimation of the loss of head in a pipe is important, since it will determine the horse-power required to ensure discharge at the required rate and pressure. To calculate the frictional pres­sure drop in a given length of pipe of a given diameter and rough­ness the following data are necessary: the rate of flow of the fluid, its viscosity and density, losses due to the presence of sharp bends or elbows in the pipe, if they impede the normal flow.

4. The rate of flow at any section of a pipe can be measured by a variety of metering devices. In a Pitot-tube, a small fluid is brought to rest in a small-bore tube, the impact pressure being measured against the static pressure of the fluid in an outer tube. In other instruments, the stream is accelerated through a Venturi or nozzle. Its kinetic energy is thereby increased, and the rate of flow can again be determined from the pressure difference.

Vocabulary

1. behavior - поведение

2. dissipated - рассеивание

3. to affect - отрицательно влиять

4. head - напор

5. viscosity - вязкость

6. discharge - подача (жидкости)

7. critical speed - критическая скорость

8. rate - зд. скорость

9. smooth - равномерный

10. pressure drop - падение давления

11. unstable - неустойчивый

12. sharp bend - изгиб под острым углом

13. to impede - нарушать

14. eddies -

15. turbulence -

16. rate of flow - скорость течения

17. roughness - шероховатость

18. metering - замер

19. kinetic energy - кинетическая энергия

20. Pitot-tube - трубка Пито

21. small-bore – отверстие не большого диаметра

22. impact pressure – динамическое давление

23. Venturio – трубка Вентури

Ответьте на вопрос: When does the fluid become unstable?

Контрольные задания

для студентов заочного отделения специальности 230111 «Техническое обслуживание средств вычислительной техники и компьютерных сетей»

 

Вариант 1