Unit 7 Well completion

Ex.1 Learn the new words.

relation – условия залегания	vat - чан
cement grout - цементный раствор	formation - пласт
productive horizon – продуктивный горизонт, продуктивный пласт	reservoir features – коллекторные свойства
drilling the pay - бурение в продуктивном горизонте	pedestal - пьедестал
control valve – контрольный отвод	flange - фланец
diversion valve – вентиль для отвода газа	guard - кондуктор
back pressure - противодавление	spouting - фонтанирование
formation exposing – вскрытие пласта	angle of inclination – угол наклона
azimuth of the borehole - азимут буровой скважины	lithological properties – литологические свойства
occurrence - залегание	precautionary measures – меры предосторожности
fittings - арматура	solution - раствор
to blowout - сфонтанировать	flow line – выкидная линия
actuating oil and gas influx вызов притока нефти и газа	to put into the commission – ввести в эксплуатацию
digging - проходка	to be limited to - сводиться к
descending - спуск

Ex.2 Read and translate the text.

Well completion

Well completion includes several stages: drilling in the productive horizon; study of productive horizon; choosing design for the borehole; setting up the wellhead; actuating oil and gas influx fro31m the formation and putting the well in commission.

In order to create good conditions for developing the well, while digging the productive horizon it is necessary to ensure the least possible disturbance of reservoir features. To reduce negative impact, the following activities must be carried out:

a) while pay drilling, back pressure should be reduced to the minimum safe value, when spouting is impossible;

b) drilling in the productive horizon, horizon evaluation, descending and cementing of flow string must be carried out quickly to save time during which the washing liquid could contact with walls of the well;

c) during the formation exposing a high-quality clay solution should be applied for minimal water loss;

d) while drilling the pay in the field with favorable geological conditions blowing out the well with air or gas is recommended.

Study of a productive horizon aims examining collector wells, relation and exploitation of the productive horizon. When drilling in the produсtive horizon, well operation is most often limited to studying the formation and conducting geophysical investigations in order to determine the angle of inclination and azimuth of the borehole, the power and interval of formation occurrence, its porosity and permeability.

Choosing design of the borehole is carried out before drilling, because it depends on well location, lithological and physical properties of formation, presence of aquifers etc.

Complete formation exposing should be carried out with all precautionary measures in wells with high formation pressure.

The equipment for wellhead set-up includes: pedestal, flange, guard, and control and diversion valve to divert gas from the annulus.

The aim of oil and gas influx procedure is to reduce the pressure onto the formation. That is why certain activities are conducted in order to make the hydrostatic pressure in the well lower than in the formation. The process of oil and gas influx is the following.

At the well top there are installed special fittings. Pipes are put down into the well up to the filter. These pipes and fittings are used for further well operation. Water is pumped into the annulus through the open valve. Solution that fills the borehole reaches the surface along the internal pipes and then gets into the receiving vat. If the formation pressure is large enough, the well may blowout. Oil goes to the upper flow line.

Ex.3 Define the part of speech of each word.

influx	physical	precautionary	along	pressure
equipment	horizon	certain	exposing	lower
create	cement	occurrence	hydrostatic	clay

Ex.4 Find pairs of words-antonyms.

Cover, preceding, positive, non-productive, top, along, increase, create, influx, put into commission, pump in, destroy, rising, internal, pump out, install, upper, complete, dismantle, lower, actuate, productive, external, quickly, reduce, across, bottom, following, expose, slow down, negative, descending, efflux, slowly.

Ex.5 Answer the following questions about the text.

1.What is the text about? 2.Which types of work does well completion include? 3.What measures should be taken in order to reduce negative effect of the factors causing deterioration of reservoir features in productive horizons? 4.Why must drilling in the productive horizon, horizon evaluation, descending and cementing of flow string be carried out quickly? 5. What factors does design of the borehole depend on ? 6. How is well top set up? 7. What is well operation most often limited to when drilling in the produсtive horizon? 8.Why is it necessary to activate the influx of oil or gas? 9. What is the procedure of oil and has influx? 10.What is the aim of this procedure?

Ex.6 Read the text again. Put the items of the plan for well completion into the right order.

1. Wellhead set-up

2. The procedure of activating oil and gas influx is the following.

3. Choosing the design of the borehole

4. Drilling pay

5. Study of a productive horizon

Ex.7 Say, if the statements are true or false. Correct the false statements.

1. The aim of oil and gas influx procedure is to make the hydrostatic pressure in the well lower than in the formation. 2. Complete formation exposing should be carried out with all precautionary measures in well with low formation pressure. 3. The principle of blowing the well is the following: through annulus dirty water and rock particles are emitted from the bottomhole to the surface. 4. The main advantage of drilling well with air or gas is ability to control strata pressure. 5. Flowing well operation may be used only if the pressure on bottomhole is less than hydrostatic pressure of liquid-gas mixture that fills the entire wellbore from the mouth up to the face. 6. Many structural alloys corrode merely from exposure to moisture in the air. 7. The drilling fluid is thyrotrophic like a non-drip paint, and when not disturbed it will form a gel. 8. A ‘Christmas tree’, or "tree", is referred to a wellhead. 9. GTL technologies create more efficient processes to generate synthetic fuels and other substances from non-oil or non-conventional feedstocks while minimising the environmental impact.

Ex.8 Insert the right word from the brackets.

1. In petroleum production, completion is the (progress/process) of making a well ready for production. 2. To (reduce/increase) negative impact, special activities must be carried out. 3. Choosing design of the borehole is carried out (after/before) drilling. 4. There are an (increasing/engineering) number of ideas coming into the market place to extend the options for openhole completions. 5. The (river/flow) pipes are seamless. 6. For all these (actions/operations) there is used a drilling rig. 7. Galvanic corrosion occurs when two different (compounds/metals) electrically contact each other and are immersed in an electrolyte. 8. Oil and gas conversion and processing research is aiming to generate cleaner sources of (energy/supply) from the nation's abundant natural resources.9. Extracting crude oil normally (stops/starts) with drilling wells into the underground reservoir. 10. Drilling fluid is thyrotrophic like a non-drip paint, and when not (interrupted/disturbed) it will form a gel.

Ex.9 Translate the following sentences into English.

1.При разбуривании продуктивного пласта следует снижать противодавление на пласт до минимально безопасного значения. 2. Для вызова притока путем замены бурового раствора жидкостью с меньшей плотностью (например, водой) скважину оборудуют по специальной схеме. 3. В состав оборудование устья скважины входят: пьедестал, фланец, кондуктор, контрольный отвод и вентиль для отвода газа из затрубного пространства. 4. Воду нагнетают в затрубное пространство через открытую задвижку с помощью насоса. 5. Одной из основных функций промывочных жидкостей является защита бурового оборудования от коррозии. 6. Глинистые растворы приготавливают из глины и воды. 7. Вязкость – свойство жидкостей и газов оказывать сопротивление перемещению одной их частицы относительно другой. 8. Водоотдача – способность раствора при определенных условиях отдавать воду пористым породам. 9. Буровые насосы предназначены для нагнетания промывочной жидкости (воды, глинистого раствора) в скважину при геологоразведочном бурении на нефть и газ.10. Газовые фильтры служат для очистки воздуха, природного или другого газа от песка, смолистых веществ, металлической окалины, пыли и других твердых частиц и механических примесей на горизонтальных участках газопроводов.

Ex.10 Retell the text “Well completion”.