Вариант V

1. Перепишите и переведите следующие предложения, обращая внимание на сложные формы инфинитива (см. Образец выполнения № 1).

1. New cities are to be constructed in this region.

2. I am glad to have been invited to this party.

3. There are some problems to be solved immediately.

4. It suggested that I must have read all of the Belgian artist and writer's books.

5. A cracking noise made me think we might have brought home an unwilling creature.

6. Both experiences have made me want to experiment and challenge myself even more.

7. They made me wait 2 and half hours before a doctor finally agreed to examine me.

2. Перепишите и переведите следующие предложения. Помните, что объектный и субъектный инфинитивные обороты соответствуют придаточным предложениям (см. Образец выполнения № 2).

1. We know the geological prospecting to be developing now.

2. Decreasing of volumes of oil extraction is said to continue till 1996.

3. Samotlorskoye deposit is known to be one of the top ten largest deposits of the world concerning oil reserves.

4. We know the existence of oil and gas resources in Siberia to have been predicted by I.M. Gubkin in 1934.

5. We know a laser to be a device that stimulates the electrons of a light-producing material to vibrate simultaneously.

6. Lasers are known to have found an application in the printing industry.

7. Light waves are now believed to be due to the motions of electrons themselves within the atoms.

8. Chemical investigations have shown each element to combine with another only in definite proportions.

3. Перепишите и переведите следующие предложения, содержащие придаточное условия. Определите тип условного предложения (см. Образец выполнения № 3).

1. If this article were on radio-electronics we should read it without dictionary.

2. It would have been impossible to launch space rockets, if we had not had the necessary polymeric materials and synthetic fuels.

3. If oil is found in a region, the oil extractive and oil processing enterprises are created.

4. If liquids expand upon freezing, an increase of pressure lowers the freezing point.

5. If the metal had been heated slowly, the first changes in its appearance would have occurred at a temperature of 1000 К.

6. It would be impossible to determine the properties of these materials without intensive studies in our research laboratory.

4. Прочитайте и устно переведите текст. Explotation of flowing wells

By flowing or gushing of an oil well is meant the process of oil motion from the bottom hole to the head of the well under the action of the formational energy.

Natural flowing of an oil well is possible only if its bottom hole pressure is greater than the hydrostatic pressure exerted on the bottom hole by the weight of the column of gas-oil mixture rising to the well head. The gas which evolves from the oil when it approaches the heard of the well is exceedingly important for flowing. The numerous bubbles of gas dispersed in the oil not only reduce its specific gravity, but also actively participate in lifting the oil, since they entrain particles of the surrounding liquid when they float to the surface.

The energy of the expanding gas is best used by fitting flowing wells with small diameter tubings which are usually lowered almost to the bottom of the well, to the perforated interval. The gas disperses uniformly over the entire cross section of the tubing as it rises and also carries along the oil near the walls of the tubes. In tubings with a great diameter partial separation of the oil and gas occurs: the oil is more saturated with gas bubbles at the central section of the tube and it moves with a greater velocity, while the oil is much less mobile at the walls of the tube, it becomes gradually degassed, and, mixing with fresh oil, increases its specific gravity, thus creating additional back pressure on the stratum. This is why flowing wells are no longer operated by withdrawing oil directly through the casing string.

When a flowing well is in operation, an excess pressure, called the buffer pressure, appears at the well head. It is approximately equal to the difference between the bottom hole pressure and the hydrostatic pressure created by the weight of the column of the oil and gas-oil mixture filling the tubing. The buffer pressure characterizes to a certain extent the productive capacity of wells at a given oil field.

The oil and gas are arranged separately in the annular space, i.e., in the annular clearance between the production casing and the tubing. There is always a gas «cushion» – free compressed gas – in the upper part of the annular space, while its remaining part is filled with oil. Almost the entire volume of the annular space becomes filled with compressed gas, if oil and gas flow from the stratum into the well in a free state.

The pressure of the gas in the annular space is determined by the difference between the bottom hole pressure in the operating well and the hydrostatic pressure created by the column of fluid in if. This quantity does not characterize operation of the well, but does give an idea of the distribution of oil and gas in the annular space.

As oil rises to the well head along the tubing, the evolution of gas from it is accompanied by a number of secondary phenomena. In particular the composition of the oil changes and it cools down. When paraffin base oil is involved cooling of the oil results in paraffin deposition on the walls of the tubes.

An increase in the volume of the free gas results in an increase in the velocity of the gas-oil mixture, and it is much higher at the well head than lower in the well.