Science – scientist – scientific

Produce – product – production – productivity – productively – producer –productive

React – reactivity – reactive – reaction

Deposit – deposition – depositing

Pass – passing – passage

Relative – relatively – relation

Soluble – solution

X. give Russian equivalents to the following phrases:

1. to take precautions 1. определяться

2. at intervals 2. зона высокого давления

3. to set in a casing string 3. принимать меры предосторожности

4. to be determined by 4. в промежутки

5. blowout preventer 5. устанавливать колонну обсадных труб

6. high pressure zone 6. превентер выброса

I. Translate the following sentences into Russian:

1. Casing may be used to exclude fluids in other intervals than that from which it is desired to produce.

2. Casing also prevents escape of formation fluids through the well from one stratum to another.

3. Setting casing is an important job in drilling most wells.

4. Casing is run in the hole to shut off troublesome water sands, high pressure gas zones, prevent caving in and protect fresh water strata.

5. The water, if not prevented from entering the oil sand, will displace the oil due to its greater specific gravity and ruin the well.

6. The number and size of the casing strings used vary with the depth and choice of the operation.

7. Each casing string is cemented in place by a slurry pumped down the pipe and up the annulus between the casing and the open hole.

8. The cement is allowed to set for several hours before drilling or other operations are recommended.

9. When casing and cement have been set in the pay zone, there must be some opening made to allow the oil and gas to pass into the well bore.

10. In drilling into high-pressure formations, the well should always be equipped with a blowout preventer.

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XII. Complete the following sentences according to the text:

1. During drilling, special precautions have to be taken...

2. At intervals the hole...

3. The depth that each string is set...

4. When a potential oil or gas bearing formation is reached...

5. The tubing is suspended from the wellhead and...

XIII. Find in the text English equivalents to the following Russian words and expressions:

Обсадные трубы, вскрытие (пласта), продуктивный пласт, техническая колонна труб, удельный вес бурового раствора, ремонт, насосно-компрессорные трубы, спускать трубы в скважину, обвал, предупреждать, перекрывать.

XIV. Translate into English:

1. Чтобы предохранить стенки скважины от обвала, их крепили и теперь еще часто крепят специальными трубами, которые называются обсадными.

2. Обсадные трубы опускаются в скважину по мере того, как она углубляется.

3. Известно, что первые обсадные трубы были деревянные, затем стали применять стальные трубы.

4. Существует много способов добычи нефти и газа.

5. Прежде чем начать бурение скважины, необходимо установить вышку на месте, выбранном для бурения.

6. Нефтяной фонтан прекращается там, где не хватает давления в пласте, чтобы выталкивать нефть из скважины.

7. Если нефть не выталкивается из пласта, то необходимо поднять давление в пласте.

8. Известно, что нефтяники могут создавать искусственное давление, и пласты начнут снова давать нефть.

9. Существуют различные способы вскрытия продуктивного пласта.

10. Когда обсадная колонна перекрывает продуктивный пласт, то обсадку простреливают.

11. Простреливание обсадной колонны, которое называется «пулевой перфорацией», производится для притока жидкости к забою.

XV. Answer the following questions on the text:

1. What is the title of the text?

2. What is the main idea of the text?

3. What precautions have to be taken during drilling?

4. Why is the hole lined with steel pipe?

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5. What is the diameter of the casing?

6. Where is the casing lowered?

7. What does the casing string consist of?

8. Why is a blowout preventer fit?

9. What tests are carried out when a potential oil or gas bearing formation is reached?

10. Where is tubing suspended?

11. What is tubing used for ?

XVI. Divide the text of the lesson into several logical parts. Find in each part key sentences containing the main information. Give your opinion of the information presented in the text. Give a short summary of the text:

CEMENTING OPERATION.

The cementing of casing in oil wells is almost a universal practice and is done for a number of reasons, depending on the particular casing being cemented. Where conductor casing is required, it must be cemented in order to prevent the drilling fluid iron circulating outside the casing and thus causing the surface erosion which the casing was designed to prevent. Surface casing must be cemented in order to seal off and protect fresh water formations and give support at the surface for the deeper strings of casing. Intermediate strings of casing are cemented in order to seal off abnormal pressure formations effectively. Isolate incompetent formations which would cause excessive sloughing unless supported by casing and cement, and shut off zones of lost circu­lation in order to allow drilling to progress further. Oil strings are cemented in order to prevent migration of fluids to thief zones and sloughing of formations which would cause a reduction in well productivity. Cement also effectively protects the casing from corrosive environments, notably corrosive fluids, which nay exist in the subsurface formations.

With a few notable exceptions, Portland cement is the principal constituent of most cementing materials. It is the ordinary cement which has been used by the construction industry for many years. However, with the advent of its use for cementing casing in oil wells, the additional requirement of pumpability at increased temperature and pressure necessitated some revisions in specifications. Additives have been developed which change the specificati­ons of Portland cements to adapt them for use in oil well cemen­ting. In order for an oil well cement to perform satisfactorily its task, certain requirements must be met.

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XVII. Translate the following text in writing. Use a dictionary:

FUNCTIONS OF WELL CASING.

Casing used in oil and gas wells is designed to serve several purposes. In supports the walls of the well and checks caving tendencies of unconsolidated formations. Although some sedimentary rocks, particularly the harder sandstones and limestones, may stand without support for long periods of time, most of soft poorly consolidated sands, shales and clays cave readily and, in doing so, endanger the drilling tools and well equipment, develop cavities about the wells and restrict progress in excavation. Casing may be used to exclude fluids in other intervals than that from which it is desired to produce also, it prevents escape of formation fluids through the well from one stratum to another. Water must be prevented from entering the oil and gas yielding strata from overlying or underlying formations. Gas and oil must be confined within the well casing so that they may not escape into overlying formations. At the surface the casing affords a means of attaching a control valve by means of which flow of gas and oil may be regulated and pressure within the well controlled. In an uncased hole, gas and oil may escape through the well into lower pressure permeable formations and be dissipated through them so that complete recovery can never be effected.

Casing must be watertight, particularly if it is to be used, in sealing off water, and it should, if possible, be made of material that resists corrosion, particularly when in contact with saline ground waters. The material the casing is made must be hard and rigid enough to resist abrasion and distortion by the contact with the exposed rocks or the drilling tools. The walls of the casing must be as thin as is consistent with the necessary strength in order to avoid undue loss