VIII. Translate into Russian paying attention to the Infinitive:

1. The properties of the rock to be drilled determine the type of the drilling bit to be used.

2. The bit is to be replaced from time to time.

3. In order to replace the bit the driller must lift it to the surface.

4. This bit is too dull to crush the hard rock.

IX. Speak on all types of bits. Lesson Nine Casing

I. Words and expressions to be remembered:

1. to reinforce - укреплять

2. to thread - навинчивать, прикручивать

3. to lower - опускать

4. to perform - выполнять .

5. aid - помощь

6. derrick – буровая вышка

7. to prevent - предотвращать

8. to penetrate - проникать

9. clearance - пространство

10. casing – обсадка, обсадные трубы

11. to fit – оснащать

12. equipment - оборудование

13. to accumulate - накапливать

14. particle - частица

15. to reduce - уменьшать

16. wear - износ

17. bit - долото

18. to subject - подвергаться

19. separation - отделение

20. valuable - ценный

21. sleeve - ниппель, муфта

22. tube – труба

23. bore hole – скважина

24. to ascend – подниматься

25. to flush – промывать

15. chiefly – в основном, главным образом

16. to ensure – гарантировать

17. removal – устранение

18. bottom hole – забой скважины

19. otherwise – иначе

20. thereby - поэтому

II. Read and translate the words:

diameter, either, clearance, equipment, wear, capable, subject, saturation, precipitate.

III. Read and translate the text: Casing

Steel casing tubes from 114 to 426 mm and over in diameter and from 6 to 13 metres long, are used for reinforcing well walls. They are either connected to each other by casing sleeves or threaded to­gether, and then lowered into the borehole, the connecting and "run­ning" (or lowering) operations being performed with the aid of special devices on the derrick. To prevent subterranean water from penetrating into the well, the clearance between the casing and the walls of the well is filled with cement injected under pressure,

During the further drilling operations the mud fluid ascends along the clearance between the drill pipes and the casing. The lower part of the production spring is fitted with special equipment for the cementing operation. The mud fluid used in drilling operations is main­ly for flushing the hole, chiefly for ensuring the removal of the cut­tings from the bottom hole to the surface as otherwise particles of the rock may accumulate on the bottom hole, thereby reducing the drilling speed and increasing the wear of the bits.

IV. Answer the following questions:

1. What tubes are used for reinforcing the walls of the well?

2. How are the tubes connected with each other?

3. Why is the clearance between the walls and the casing filled with cement?

4. What is the mud fluid used for?

V. Arrange the following words in pairs of synonyms:

reinforce, perform, clearance, aid, well, help, make, consolidate, borehole, space, lower, put down, important, efficient

VI. Arrange the following words in pairs of antonyms:

lift, increase, destroy, disconnect, reduce, lower, reinforce, connect, bottom, inefficient, important, head, prevent, permit

VII. Find Gerund in the sentences and try to translate the sentences into Russian:

1. Steel casing tubes are used for reinforcing well walls.

2. To prevent subterranean water from penetrating into the well the clearance between the casing and the walls of the well is filled with cement under pressure.

VIII. Translate into English:

1. Для укрепления стенок скважин используют стальные обсадные трубы.

2. Между собой трубы соединяются с помощью резьбы.

3. Спускоподъемные операции ведутся различными приспособлениями.

4. Затрубное пространство заполняют цементом.

5. Иногда частицы пород накапливаются на забое скважин.

6. Это уменьшает скорость бурения и увеличивает износ долот.

IX. Speak on:

1. The sizes of the casing tubes and their using for.

2. The mud fluid using for drilling operations.