WELL COMPLETION AND WORкOVER OPERATIONS

EXERCISE 1 Read and translate the text "Completion", using the words after the text.

Completion

After drilling and casing the well, it must be 'completed'. Completion is the process in which the well is enabled to produce oil or gas. In a cased-hole completion, small holes called perforations are made in the portion of the casing which passed through the production zone, to provide a path for the oil to flow from the surrounding rock into the production tubing. In open hole completion, often 'sand screens' or a 'gravel pack' is installed in the last drilled, uncased reservoir section. These maintain structural integrity of the wellbore in the absence of casing, while still allowing flow from the reservoir into the wellbore. Screens also control the migration of formation sands into production tubulars and surface equipment, which can cause washouts and other problems, particularly from unconsolidated sand formations in offshore fields.

After a flow path is made, acids and fracturing fluids are pumped into the well to fracture, clean, or prepare and stimulate the reservoir rock to produce hydrocarbons into the wellbore. Finally, the area above the reservoir section of the well is packed off inside the casing, and connected to the surface via a smaller diameter pipe called tubing. This arrangement provides a redundant barrier to leaks of hydrocarbons as well as allowing damaged sections to be replaced. Also, the smaller diameter of the tubing produces hydrocarbons at an increased velocity in order to overcome the hydrostatic effects of heavy fluids such as water.

In many wells, the natural pressure of the subsurface reservoir is high enough for the oil or gas to flow to the surface. However, this is not always the case, especially in depleted fields where the pressures have been lowered by other producing wells, or in low permeability oil reservoirs. Installing a smaller diameter tubing may be enough to help the production, but artificial lift methods may also be needed. Common solutions include downhole pumps, gas lift, or surface pump jacks. The use of artificial lift technology in a field is often termed as "secondary recovery" in the industry.

The words to be memorized:

artificial lift methods – методы механической добычи

cased-hole completion – заканчивание скважины посредством обсадной колонны

completion – заканчивание скважины

depleted field – истощенное месторождение

formation sand – песок из пласта

fracturing fluid – жидкость для гидроразрыва

gravel pack – гравийный фильтр

hole completion - заканчивание скважины

leak – утечка, течь

permeability - проницаемость

to produce – добывать

producing well – добывающая скважина

production tubular – эксплутационная скважина

perforation – перфорационное отверстие

production zone – продуктивная зона

production tubing – эксплутационная насосно-компрессорная колонна

redundant – излишний, избыточный, резервный

reservoir rock – порода- коллектор

reservoir section – коллекторская порода

screen – фильтр

secondary recovery – вторичное извлечение

unconsolidated sand – неуплотненный песок

washout – размыв, отверстие в бурильной трубе

EXERCISE 2 Read and translate the text "Fishing tools", using the words after the text.

Fishing tools

Sometimes items of drilling or production equipment get lost in the borehole. When an item of equipment is lost in the hole, it is called a “fish”. A lost item is also called “junk”. Operations in the wellbore cannot continue until the fish or the junk is recovered from the hole. To recover the lost item, a fishing job is necessary. Special fish­ing tools are used for latching on to the fish and pulling it out to the surface. There are many types of fishing tools. For example, there is a type of fishing tool called a “junk bas­ket”, and there is another type called a “spear”. These fishing tools are very different. The spear is used to recover lost tubing. The spear enters the bore of the lost pipe. The diam­eter of the spear, therefore, must be smaller than the diameter of the pipe in the hole. When the spear enters the pipe, its teeth push out and grip the inner sides of the pipe tightly. Then it is usually possible to pull the fish out of the hole.

The junk basket is used for latching on to smaller pieces of junk. It is used for recovering lost pieces of equipment, for example. The bottom part of the basket is a shoe with hard-faced teeth. The shoe has a hole in its center. The fish is forced through the hole and enters the barrel of the basket. Spring-loaded fingers prevent the fish from drop­ping out of the barrel and falling back into the well.

Before fishing can begin, the string must be tripped out of the hole. The string is broken out in stands and the stands are stood back in the derrick. After that the fishing can begin.

The words to be memorized:

1. Annual – ежегодный

2. Borehole – буровая скважина

3. Coil tubing – гибкие трубы

4. Displacement of down hole fluid – замещение внутри скважинной жидкости

5. Downholetubing – скважинный трубопровод;

6. Fishing jobs – ловильные работы

7. Fishing tools – инструменты для ловли

8. Fluid – жидкость

9. Junk basket – шламоловка

10. Junk – металлические обломки

11. Latch on – прикреплять

12. Maintain – позволить, поддержать

13. Mandatory – принудительный

14. Production rate – дебит

15. Reserve – обратный

16. Solvent – растворитель

17. Spear – внутренняя труболовка

18. Spring-loaded fingers – подпружиненные пальцы.

19. Squeeze – сжатие

20. Treatment – обработка

21. Water-sensitive – чувствительный к воде

22. Well killing – глушение скважины

23. Wire line technique – канатная техника

EXERCISE 3 Answer questions about the text.

1. Why is a junk basket hollow?

2. Why are there many types of fishing tools?

3. What is a spear used for?

4. What is a junk basket used for?

5. How is usually an item lost in the hole called?

6. What is the purpose of fishing jobs?

7. On what condition can fishing jobs start?

EXERCISE 4 Are the following statements true or false? Correct the false ones with the right information and discuss your answers with a partner.

1. To recover the lost item, a fishing job isn't necessary.

2. A lost item is also called “fish''.

3. Before fishing can begin, the string mustn't be tripped out of the hole.

4. Sometimes production equipment get lost in the borehole.

5. The diameter of the spear must be bigger than the diameter of the pipe in the hole.

EXERCISE 5 Insert the omitted word from the text

1. The junk __________ is used for latching on to smaller pieces of junk.

2. The shoe has a hole in its __________.

3. The fish is forced through the __________and enters the barrel of the basket.

4. Spring-loaded fingers prevent the__________ from dropping out of the __________and falling back into the well.

5. Operations in the wellbore cannot __________until the fish or the junk is recovered from the hole.

6. The __________is used to recover lost tubing.

7. The spear enters the bore of the lost __________.

8. The bottom __________of the basket is a shoe with hard-faced teeth.

EXERCISE 6 Make up sentences out of two parts from the table:

EXERCISE 7 Connect the terms with their definitions.

EXERCISE 8 Read and translate the texts.

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