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Файл:Нефтегазовое дело. Бурение скважин (на английском языке) = Oil and gas drilling engineering through English. Учебное пособие.pdf
10. Why are redundant safety systems and highly trained personnel
required by law in all countries?
Drilling rig
A drilling rig is a machine which creates holes (usually called
boreholes)
or shafts in the ground. Drilling rigs can be massive structures housing
equipment used to drill
water wells, oil we ll s, or natural gas extraction wells, o r
they can be small enough to be moved manually by one person. They sample
sub-surface mineral deposits, test rock, soil and groundwater physical
properties, and also can be used to install sub-surface fabrications, such as
underground utilities, instrumentation, tunnels or wells. Drilling rigs can be
mobile equipment mounted on trucks, tracks or trailers, or more permanent
land or marine-based structures (such as
oil platforms, commonly called
'offshore oil rigs' even if they don't contain a drilling rig). The term "rig"
therefore generally refers to the complex of equipment that is used to penetrate
the surface of the Ear th' s
crust.
Drilling rigs can be:
• Small and portable, such as those used in mineral exploration drilling,
water wells and environmental investigations.
• Huge, capable of drilling through thousands of meters of the Earth's
crust. Large "
mud pumps" circulate drilling mud (slurry) through the drill bit
and up the casing annulus, for cooling and removing the "cuttings" while a well
is drilled. Hoists in the rig can lift hundreds of
can force
acid or sand into reservoirs to facilitate extraction of the oil or natural
tons of pipe. Other equipment
gas; and in remote locations there can be permanent living accommodation and
catering for crews (which may be more than a hundred). Marine rigs may operate many hundreds of miles or kilometers distant from the supply base with infrequent crew rotation or cycle.
Oil and natural gas drilling rigs can be used not only to identify geologic
reservoirs but also to create holes that allow the extraction of oil o r natural gas
from those reservoirs. Primarily in onshore oil and gas fields once a well has
been drilled, the drilling rig will be moved off of the well and a service rig (a
smaller rig) that is purpose-built for completions will be moved on to the well
to get the well on line. This frees up the drilling rig to d rill another hole and
streamlines the operation as well as allowing for specialization of certain
services, i.e., completions vs. dril ling.
Oil well drilling utilises tri-cone roller, carbide embedded, fixed-cutter
diamond, or diamond-impregnated drill bits to wear away at the cutting face.
This is preferred because there is no need to return intact samples to surface for
assay as the objective is to reach a formation containing oil or natural gas.
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Sizable machinery is used, enabling depths of several kilometers to be
penetrated. Rotating hollow drill pipes carry down
bentonite and barite infused
drilling muds to lubricate, cool, and clean the drilling bit, control downhole
pressures, stabilize the wall of the
borehole and remove drill cuttings. The mud
travels back to the surface around the outside of the drill pipe, called the
annulus. Examining rock chips extracted from the mud is known as mud
logging. Another form of wel l logg ing is electronic and is frequently employed
to evaluate the existence of possible oil and gas deposits in the
can take place while the well is being drilled, using
Measurement While
borehole. This
Drilling tools, or after drilling, by lowering measurement tools into the newly
drilled hole.
The rotary system of drilling was in general use in Texas in the early
1900s. It is a modification of one invented by Fauvelle in 1845, and used in the
early years of the oil industry in some of the oil-producing countries in Europe.
Originally pressurized water was used instead of mud, and was almost useless
in hard rock before the diamond cutting bit. The main breakthrough for rotary
drilling came in 1901, when
steam-driven rig and of mud instead of water in the
The drilling and production of oil and gas can pose a
hazard to the
environment from the ignition of the entrained gas causing
Anthony Francis Lucas combined the use of a
Spindletop discovery well.
safety risk and a
dangerous fires and also from the risk of oil leakage polluting water, land and
groundwater. For these reasons, redundant safety systems and highly trained
personnel a re required by law in all countries with significant production.
(abridged from https://en.wikipedia.org/wiki/Drilling_rig)
Text 4.
Read the text about well drilling, don’t consult a dictionary. Is there
any unknown information for you? Say what is new for you (see example in
Unit 1).
Read again, then complete the sentences using the text.
1. … might be run in hole and cemented…
2. … casing is inse rted into the well once the drill pipe…
3. … logging tells the industry…
4. The swivel connects to the kelly…
5. … the pipe to the earth.
6. … rotary table , turbodril l, dynadrill…
7. … being at the p oint of impact…
8. … a drilling location is graded…
9. … the drilling location and heads on…
10. … can last anywhere from a few days…
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Well drilling
Oil well drilling has been the main means of producing oil ever since
Colonel Drake drilled that first well in 1859, which signaled the start of the
American petroleum industry .
Drilling techniques and equipment have changed throughout the decades
from cable too ls to r otary-based on es, from straight holes to sidetrack and GPSbased directional drilling, and from “guess” and “feel” to computer-based accuracy.
The biggest improvement in oil well drilling, however, has been in the
preparatio ns pr ior to e ver br ea k in g gro und .
The drilling of a well, especially a “wildcat” is a milestone event, involving practically every sub-discipline of the oil business and signifies the start of
direct field inve s ti ga t ion.
For the oil exploration and production company, the drilling of the well
represents final exploration sunk costs prior to the possibility of recovering
those costs through well production revenues. For the petroleum geolo gists and
the reservoir engineer the drilling of the well represents the final confirmation
of the interpretation of numerous strands of indirect evidence of oil’s presence.
For the production a nd facilities engineers, it repres ents the soon to be realized
asset requiring sub-surface and surface management and equipment to maximize product ion. And for the drilling engineer well – it is time to ea rn their pay .
Through experience and communications with geologists, reservoir engineers, production engin eers and facilities engineers – the technical team – the
drilling engineer develops a plan for reaching the targeted formation at the
bottomhole location identified, from the surface location specified – at the cost
authorized.
Before ever setting up on the drill location, the drilling engineer has
gained all of the necessary approvals to drill from the company and regulatory
authorities. The appropriate hole dimensions, the wireline testing procedures,
the well cas ing program and the cement volumes are all known upfront.
The drilling engineer has already scheduled an oil well drilling rig, alerted a wireline and cementing service company, ordered necessary drilling fluids,
tanks, pipe and safety equipment (inc luding blowout prevent ion equipment).
Operations normally proceed on a 24 hours per day basis and depending
on methods, depths, rock types encountered, can last anywhere from a few days
to several month s.
History has shown that rarely do operations proceed in a “normal” fashion. Each well has its own story. It is quite normal to encounter hard rock zones
and experience sand control problems, as well as for minor equipment breakdowns to occur – right next to a well which didn’t experience half of the prob-
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lems. Drill bits wear out, wrong auxiliary equipment is delivered, various other
events happen that slow progress, raise corporate anxieties and compromise
schedules.
Due to all of the proble ms which can and do happen on site, oil companies have increasingly focused on safe operations. This is something everyone
can control.
Most oil well drilling operations are actually completed by drilling service companies with oil company drilling engineers supervising. Oil companies
are using their natural leverage by insisting on safe operations by contractors
which minimize employee “accidents” and environmental impacts and maximize accountability. Drilling service companies with poor safety records are not
kept for long.
Operations proceed in accordance with terms of a permit issued by
the regulatory agency with jurisdiction. Normally, a drilling location is
graded, a conductor pipe is set to support subsequent casing strings, blo wout control equipment is installed and tested for well safety, the drilling rig
and auxiliary equipment is moved in and set up, and drilling operations are
underway.
Contemporary drilling operations consist of downhole tools (drill bits,
reamers, shock absorbers, etc.), drill string components (drill collars, drillpipe,
kelly, etc.) suspention equipment (rotary swivel, hook, blocks and wire rope),
supporting structures (derrick), rotary drive mechanism (rotary table, turbodrill,
dynadrill), hoisting equipment (drawworks, auxiliary brakes, cathead, etc.),
transmission system (mechanical transmission, clutch, belts and chains), prime
movers (diesel, turbo-electric), hydraulic circulating system (slush pump, high
pressure surface equipment, drill string, shale shaker, desander, degasser, mud
tanks/mixers), and rig floor and wellhead accessories/tools (cat lines, elevators,
rotary slips, power slip, safety clamps, power tongs, rig instrumentation, blowout prevention equipment, etc.)
Although each area is vitally important to safe and efficient drilling operations, the drill string including the downhole tools is the most important area; being at the point of impact, transmitting surface derived energy into bottom-hole torqu e an d hole dig gi ng.
The drill string/subsurface assembly is composed primarily of a swiwel,
a kelly, a drill pipe, a drill collar and a bit. The swivel connects the rotating
drill string to the drilling rig support system. It suspends th e drill string, pe rmits free rotation and serves as the means for drilling fluid circulation. Drilling fluid is circulated through the drill pipe and bit to cool the bit and assist in
cutting removals. The drilling fluid also serves to coat the open-hole to prevent cave-ins and prevent a n y r eservo ir fluids (oil, gas and water) encountered
from rushing in.
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The swivel connects to the kelly, which is usually either a square or hexagonal-sided pipe of about 43 feet l ong that transmits the torque from the rotary
table on the rig floor to the drill string causing the bit to turn and make hole.
Drill pipe sections are connected to the kelly one at a time allowing the bit to
work deeper and dee per in the h ole.
The drill collar is a heavy-walled pipe which connects the drill bit to the
drill pipe. Its weight puts pressure on the bit to keep it working at the bottom of
the hole.
The drill bit is the primary downhole tool, cutting up formation as it rotates. Diamond bits are used for hard formations. However, tri-coned steelteethed bits are most commonly used today.
Sometimes, geologists inspect the cuttings that are circulated to surface to identify and confirm the formation that is currently bring drilled.at
various and defined intervals, the well may be logged by wireline service
companies. Why is this done? Well logging tells the industry experts the
formations they are in, the fluids present within th e formation (including oil)
and the quality of the cement job. In some drilling operations, wells are
logged as they are be ing using sophisticated tools which continuously transmit vital downhole information to surface without having to cease holemaking.
Metal pipe called surface casing is inserted into the well once the drill
pipe is removed, and is cemented to the earth by cementing service companies.
Cement is pumped and circulated within the well to permanently affix the pipe
to the earth. This provides support and limits communication between the surface and the subsurface to just that spa ce inside of the pipe.
Subsequent drilling punctures the bottom of the recently placed cement
sheath and continues down to the objective depth. To drill deeper, the rig crew
performs the seemingly routine act of ceasing rotary table rotation and mud circulation, liftin g the drill s tring, setting i t on s lips a t the f loor, brea king th e joint
between the kelly and the topmost drill pipe with tongs, screwing on an additional length of drill pipe at the kelly, lifting the string again, removing the
slips, lowering the string downhole and reestablishi ng mud circulation and rotary table rotation.
Intermediate casing might be run in hole and cemented, too, depending
on well design criteria and formation characteristics. When the total depth is
reached a final cementing job is conducted to either plug the well back up because no significant hydrocarbon was found, or to secure the production casing
string in place for future completion and production.
The drilling contractor rigs down and moves off of the drilling location
and heads on to the next assignment.
(abridged from https://postamericana.wordpress.com/tag/oil-well/)
75
Text 5
Read the text about blowout preventors, don’t consult a dictionary. Is
there any unknown information for you? Say what is new for you (see example in Unit 1).
Read once again and answer the following questions in Russian.
1. What is petroleum and how did it appea r?
2. What kinds of fossil fuels do you know and how do they differ from
each other?
3. What does petroleum consist of?
4. What sedimentary roc ks are the most common petroleum reservoirs?
5. What m e thods are used nowadays to locate petroleum traps?
6. How does the seismic exploration f unction?
7. What does a method of coiled-tubing drilling employ?
8. What are the three methods used in a drill bit rotation to turn the bit
downhole?
9. What are a rotary hose and mud swivel attached to the top of the kelly for?
10. What is a kelly and what is its function?
Read once again an d make a summary (see examples in Unit 2).
Blowout preventers
A drilling mud should have sufficient density (mud weight) to prevent
(hydrostatically) any gas, oil or saltwater from entering the wellbore uncontrolled. Sometimes however, these formation fluids do enter the wellbore under
great pressure. When it happens, a well is said to “take a kick”. It is especially
risky if the f luid is a gas or oil.
To guard against the dangers of such events, rigs are usually equipped
with a stack of Blowout Preventers (BOPs). Depending on the we ll depth and
other circumstances, there will be several BOP units bolted together and then to
the surface casing flange. One or more of these BOPs can be engaged to seal
off the wellbore if a kick occurs. Multiple BOPs in the stack provide flexibility
and redundancy in case of a fail ure.
At the top of the BOP stack is a bag type preventer commonly referred to
as a Hydril. This unit contains a steel ribbed, elastometric insert which can be
expanded hydraulically to seal the annulus. Below the bag preventers are the
ram-type preventers with hydraulically driven rams that close against the pipe
or against themselves, thrusting in from opposite sides of the pipe. These preventers can be pipe, blind or shear rams, pipe rams have heads with a concave
76
shape to grip the pipe and form a seal around it; they accomplish the same
function as the bag preventer but are rated at higher pressure. Blind rams come
together over the hole to form a fluid-tight seal against one another in the event
the pipe is not in the well or if it has parted and fallen down into the wellbore.
Shear rams sever the pipe before sealing together.
Below the blowout preventers is the drilling spool. It has an opening in
its side to allow drilling mud and the kick fluids to be pumped out. A highpressure choke line connected to the spool with a special back-pressure valve
(the choke) in the line. During well-control procedures, the choke is used to
hold back-pressure on the annulus while heavier mud is pumped down the drill
string to kill the kick. If the invading fluid contains gas, the gas must be removed from the mud exiting the well. Gas-cut mud from the choke is sent to a
gas separator vessel. The gas is flared and the mud is returned to the pits for reconditioning.
Casing and liner. When a well is being drilled, exposed formations must
be periodically covered and protected by a steel pipe. This is done for several
reasons – to keep the hole from caving it, to protect the formations being dril le d
and/or to isolate different geological zones from each other. These protective
pipes are called casings and liners. Casing refers to pipe that starts at the surface or mud line and extends down into the borehole. The term “liner ” applies
to pipe whose upper end does not reach the surface or mud line but is inside
and overlaps the bottom of the last casing or liner. Casing and liners are either
totally or partially cemented in place .
Casing. Two, three or more casing strings may be run in a well, with the
smaller pip e being run inside the larger sizes, and the smaller ones going deeper
than the larger. The “surface casing” is run and cemented at a depth to protect
freshwater aquifers and to avoid mud seepage into shallow sand and gravel
beds; it might be set at about 2000 ft. The next string is the “intermediate” casing. It is run and cemented when there is a need to change the mud to a density
that can’t be tolerated by the exposed formations or by the surface casing. Below the intermediate casing may be a nother string of casing or a liner.
Liners. It may not be necessary, economical or practical to line the entire,
already-cased hole all the way to the surface just to protect the lower open hole.
This is especially true as the hole nears total depth and becomes smaller. So a
liner is run through from the bottom of the hole, up into the casing, overlapping
it by several hundred feet. Liners are held in place inside the casing by special
tools called liner hangers. The practice of running a liner protects the last open
hole interva l, whic h o fte n includes the reservoir section.
Cementing. After a string of casing or a liner has been properly landed in
the hole, a cement slurry is mixed and quickly pumped down the inside of the
casing (or liner). Pressure drives it out the bottom and up into the annular sp ace
77
between the pipe and the hole wall. Cement is followed downhole by just
enough fluid to push all but th e last p art of i t out of th e casin g or li ner. On ce all
the cement hardens, that small quantity still inside the casing or liner is drilled
out and the hole proceeds into a few feet of new rock beyond the end of the
casing. Then the casing or liner is pre ssur e-tested to see how much mud weight
it will be able to hold, for future reference. If it fails the test, a remedial cement
job (squeeze) may be required. Once the cement job passes the pressure test,
drilling can res ume.
Producing petr o le um. Well completion. The next step, after setting casers
and liners, is the completion phase of a well. Completion simply means making
the well ready to produce oil and gas under controlled pressures and flow r ates.
If the producing formation is strong enough, as in the case of the limestone, a
length of casing can be cemented immediately above it, leaving the producing
formation unsupported. This is called an open hole completion. If the reservoir
rock needs s upport, other methods can be used.
Perforated casing or liner. In this method, casing or liner is run all the
way through the producing zone and cemented in place. Then, holes are shot
(by explosive charge) through the casing and cement, into the formation. These
perforations are cr e ated with a per f or ating gun that is lowered into th e hol e on a
wireline. The gun is then fired electrically, and powerful, shaped charges perforate the pipe and the zone at predetermined intervals. Once the perforations
have been made, oil and/ or gas can flow into the casing.
Perforated or slotted liner. In the second method, a pre-perforated or slotted liner (with holes or slots that are level with the productive zone is hung
from the bottom of the last string of casing. If the production formation is weak
or poorly consolidated, sand and other solids will be carried into the well as the
oil or gas is produced. To prevent this “sand production”, the slotted or perforated liner may contain a wire-wrapped or a prepacked-gravel protective layer
to keep the sa nd from enter ing the wellbore.
Gravel packing. Another approach that is helpful if the producing formation is weak (such as loose sand), and must be supported or held back, is the
conventional gravel pack. A gravel packing operation consists of circulating
and placing carefully sized gravel into the annular space between the liner and
the wellbore wall. The pack forms a permeable layer to exclude any formation
particles from the wellbor e th at becomes loose duri n g pro du ct io n.
(abridged from http://www.studfiles.ru/preview/4616339/)
6. B r a i n s t o r m !!!
Look at the chart below. It gives basic parts of a drilling unit. English
and Russian terms are given in an alphabetic order, try to match terms as
terminological equiv alents (for help see Appendix)
78
1
Annular blowout preventor
Балкон верхового рабочего
2
Blowout preventor stack
Блок противовыбросовых превенторов
3
Brace
Бурильные трубы
4
Cathead
Буровая вышка
5
Catline boom
Буровая лебедка
6
Cellar
Буровой канат
7
Choke maniford
Буровой крюк
8
Crown block
Буровой шланг
9
Crown platform (crow’s nest)
Буровые насосы
10
Degasser
Бытовка
11
Derrick (mast)
Ведущая труба
12
Desanders and desilters
Вертлюг
13
Dog house
Вибросита
14
Drawworks
Газосепаратор для бурового раствора
15
Drill (derrick) floor
Гасители пульсаций
16
Drill pipe
Гидравлические аккумуляторы (для ПВО)
17
Driller’s console
Дегазатор
18
Drilling line
Емкости для бурового раствора
19
Duck’s nest
Емкость для долива скважины при подъеме труб
20
Elevators
Емкость для топлива
21
Fingers
Запасной амбар для бурового раствора
22
Fuel tank
Запасные емкости
23
Gerontimo line
Кронблок
24
Girt
Кронблочная площадка
25
Hook
Лестница
26
Housting line
Линия для выхода бурового раствора
27
Hydraulic accumulation
Линия для закачки бурового раствора
28
Kelly
Мостки для сброса и подъема труб на площадку
29
Leg
Обвязка вышки
30
Monkey board
Опора вышки
31
Mouse hole
Отверстие в подкронблочной площадке
32
Mud (rotary) hose
Пальцы для свечей
33
Mud discharge line
Первичные двигатели (генераторы)
34
Mud pumps (hogs)
Перила
35
Mud return line
Пескоотделители и илоотделители
36
Mud tanks (pits)
Плашечные противовыбросные превенторы
37
Mud-gas separator
Подвышечное основание
38
Pigpen
Подкронблочная площадка вышки
39
Pipe racks
Пояс вышки
40
Pipe ramp (V-door)
Превентор универсальный гидравлический (ПУГ)
41
Power tongs
Пульт бурильщика
42
Prime movers
Рабочая площадка бурового станка
43
Pulsation dampeners
Роторный стол
44
Ram blowout preventors
Силовой ключ
45
Rat hole
Стеллажи для труб
46
Reserve pit
Стояк для бурового шланга
79
47
Reserve tanks
Стрела натужного троса
48
Rotary table
Талевый блок
49
Shale shakers
Трос для аварийной эвакуации верхового рабочего
50
Shock hose
Трос лебедки
51
Stairways
Шахта устья скважины
52
Standpipe
Шланг-амортизатор
53
Substructure
Шпилевая катушка
54
Swivel
Штуцерный манифольд
55
Traveling blocks
Шурф для квадрата
56
Trip tank
Шурф для свечей
57
Water table
Элеватор
Look at the diagram showing basic parts of a drilling unit. Observe and
learn the drilling unit structure (for help see Appe ndix).
7. Writing
Some people use electronic translator programs, they do not understand that such translation cannot be perfect. Correct these Google translation texts consulting or iginal English petroleum drilling engineering text s.
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