Schlumberger 1999

DRILLING

Making a hole or well to make access into reservoir and to produce hydrocarbon (oil & gas) from subsurface.

To collect the subsurface geological and reservoir data/information for further hydrocarbon exploration as well as development.

ChristmasTree

Pipeline to Flow

Process and

Storage

Surface Casing

Intermediate Casing

Production Casing

CompletionFluid

CementPacker

Cement

Cement

Tubing

WellFluids

Oil or Gas Zone

Perforations

OIL EXTRACTING HISTORY

In the earliest day of oil production, oil was collected from surface seepages.

Mine shafts were dug to make a well (like water well in Java) to produce shallow oil.

In the early 19th century peoples developed cable tool drilling

DRILLINGTYPE OF DRILLING : Cable Tool Drilling Rotary Rig Drilling

TYPE OF RIG : Onshore drilling rigs Semi-submersible rigs Jack-up units

TYPE OF WELL DRILLING : Conventional Drilling Directional Drilling Slant Drilling

CABLE TOOL DERRICK

JACK UP UNIT

A jack-up unit

is a barge with legs that can be lowered or raised. The barge is towed

to the drilling location with its legs in the raised position. Once in position, the legs are lowered. When they reach the sea-bed, the barge's body is hoisted above the water, creating a stable drilling platform. The length of the legs determines the depth of water in which a jack-

up barge can be

used. They can generally be used in up to 100 meters of water. Jack-up barges are widely employed in the relatively shallow waters of the North Sea's Southern basin.

SEMI-SUBMERSIBLE RIG

A semi-submersible drilling rig

is normally a self-

propelled working platform supported by vertical columns on submerged pontoons. By varying the amount of ballast water in the pontoons, the unit can be

raised or lowered in the water.

A semi-submersible vessel is normally held in position by up to eight very large anchors, or by dynamic positioning: computer controlled directional propellers to keep the vessel stationary relative to the sea-bed, compensating for wind, wave or current.

Semi-submersibles can drill in water depths to 300 meters or more all year round.

SETTING UP THE RIG

Depending upon the remoteness of the drill site and its access, equipment may be transported to the site by truck, helicopter or barge.

Some rigs are built on ships or barges for work on inland water where there is no foundation to support a rig (as in marshes or lakes).

Once the equipment is at the site, the rig is set up. Here are the major systems of a land oil rig:

Power System

Mechanical System

Rotating Equipment

Casing

Circulation System

Derrick

Blowout

Preventer

RIG EQUIPMENT POWER AND MECHANICAL SYSTEMS

Mechanical system - driven by electric motors hoisting system - used for

lifting heavy loads; consists of a mechanical winch (drawworks) with a large steel cable spool, a block-and- tackle pulley and a receiving storage reel for the cable

turntable - part of the drilling apparatus

Power System large diesel engines - burn

diesel-fuel oil to provide the main source of power

electrical generators - powered by the diesel engines to provide electrical power

RIG EQUIPMENT THE DERRICK

Derrick - support structure: holds the drilling apparatus tall enough to allow new

sections of drill pipe to be added to the drilling apparatus as drilling progresses

Blowout preventers and Rams - high-pressure valves (located below the rotary table or on the sea floor) seal the high-pressure drill

lines and relieve pressure when necessary to prevent a blowout (uncontrolled gush of gas or oil to the surface, often associated with fire)

Can shut off either the annular space (between pipe and well) or the complete hole.

RIG EQUIPMENT ROTATING EQUIPMENT

Rotating equipment - used for rotary drilling

swivel - large handle that holds the weight of the drill string; allows the string to rotate and makes a pressure-tight seal on the hole

kelly - four- or six-sided pipe that transfers rotary motion to the turntable and drill string

turntable or rotary table - drives the rotating motion using power from electric motors

drill string - consists of drill pipe (connected sections of about 30 ft / 10 m) and drill collars (larger diameter, heavier pipe that fits around the drill pipe and places weight on the drill bit)

Drill bit(s) - end of the drill that actually cuts up the rock; comes in many shapes and materials (tungsten carbide steel, diamond) that are specialized for various drilling tasks and rock formations

Casing - large-diameter concrete pipe that lines the drill hole, prevents the hole from collapsing, and allows drilling mud to circulate

RIG EQUIPMENT THE MUD CIRCULATION PROCESS

There's more to drilling than simply rotating the bit.

Fluid is circulated while the drilling proceeds.

Powerful pumps move the fluid down the pipe, through the bit and back to the surface, carrying the cuttings and other debris with it.

Thus, on a rotary rig (unlike the cable tool), drilling can be continuous as stopping to bail the cuttings is no longer required.

The drilling mud also stabilizes the walls of the hole.

RIG EQUIPMENT CIRCULATION SYSTEM

Circulation system - pumps drilling mud under pressure through the kelly, rotary table, drill pipes and drill collars pump - sucks mud from the mud pits

and pumps it to the drilling apparatus pipes and hoses - connects pump to

drilling apparatus mud-return line - returns mud from hole shale shaker - shaker/sieve that

separates rock cuttings from the mud shale slide - conveys cuttings to the

reserve pit reserve pit - collects rock cuttings

separated from the mud mud pits - where drilling mud is mixed

and recycled mud-mixing hopper - where new mud is

mixed and then sent to the mud pits

RIG EQUIPMENT THE

DRILLSTRING

CONTROLLING THE WEIGHT ON THE BIT

The weight is held partly by the hook etc. If not, the drill bit wouldnt turn! Collars are added to the drill string to add more weight

Hence the driller can control the weight on the bit by adding/ removing collars or by raising/lowering the swivel tackle.

TYPE OF BIT -

Which bit?

Largest bit is used first, decreasing with depthFor each formation & depth have a particular set of jet sizes, gallons per minte, pump strokes per minte, minimum annular velocity (speed mud returns at to keep the hole clean), bit hydraulic horsepower.Hence the hydraulic and bit programs work in tandem to most efficiently drill the well giving best cost per foot, drilling time, minimum down time.

CONTINUING THE DRILLING PROCESS

Drilling continues in stages: Drill run and cement new casings, then drill again.

When the rock cuttings from the mud reveal the oil sand from the reservoir rock, the final depth may have been reached.

At this point, the drilling apparatus is removed from the hole and perform several tests to confirm this finding: Well logging - lowering electrical and gas sensors into the hole

to take measurements of the rock formations Drill-stem testing - lowering a device into the hole to measure

the pressures, which will reveal whether reservoir rock has been reached

Core samples - taking samples of rock to look for characteristics of reservoir rock

DRILLING PROBLEMS

Other Drilling ProblemsOther Drilling Problems

PRODUCING SAND

WELL COMPLETION TYPE

1. 1. OpenholeOpenhole CompletionCompletion

OpenholeOpenhole completion completion merupakanmerupakan penyelesaianpenyelesaian sumursumur dimanadimana casing casing dipasangdipasang hanyahanya sampaisampai didi atasatas zonazona produktifproduktif (interest zone). (interest zone). JadiJadi sumursumur diproduksidiproduksi dengandengan kondisikondisi terbukaterbuka didi sepanjangsepanjang zonazona produksiproduksi..

CASING SHOE

PACKER

CEMENT

CASING

PRODUCTION STRING

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2. Liner Completion

Ada dua model penyelesaian sumur menggunakan Liner Completion :

1. Screen Liner CompletionCasing diset sampai di atas zona produksi yang kemudian digabungkan dengan kombinasi liner dan screen yang tidak disemen di seluruh permukaan zona produksi

2. Perforated Liner Completion

Metode penyelesaian sumur dengan melakukan pemasangan liner dan disemen pada zona produktif yang kemudian dilaksanakan pelobangan (perforated) pada zona-zona yang paling produktif

CASING SHOE

PACKER

CEMENT

CASING

PRODUCTI ON STRING

LINER HANGER

SLOTTED LINER

LINER SHOE

OIL SAND

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Perforated casing completion adalah penyelesaian sumur dengan menutup semua zona produktif dengan menggunakan casing dan disemen kemudian dilakukan perforasi (pelubangan) pada daerah-daerah produksi di lubang sumur

CASING SHOE

PACKER

CEMENT

CASING

PRODUCTION STRING

PERFORATION

OIL SANDP

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3. Perforated Casing Completion3. Perforated Casing Completion

THE MAST (CHRITMAST-TREE)

Setelah

pemboran

dinyatakan

berhasil

dan

mendapatkan

minyak

atau

gas, maka

di

kepala

sumur

dipasang

chritmas

tree yang didefinisikan

sebagai

rangkaian

dari

valve dan

fitting yang digunakan

untuk

control produksi

dan disambungkan dengan bagian

atas

tubing head. Pertama

kali christmas

tree digunakan

untuk

tekanan

aliran

rendah

dan

menengah

dari

suatu

sumur, dimana

rangkaian

dari

tees, elbows, nipples, valve yang dibeli

secara

terpisah

dan

dirangkaikan

jadi

satu

di

lokasi.

PRODUCING WELL COMPLETION

Slide Number 1DRILLINGOIL EXTRACTING HISTORYDRILLINGCABLE TOOL DERRICKSlide Number 6JACK UP UNITSEMI-SUBMERSIBLE RIGSETTING UP THE RIGRIG EQUIPMENTPOWER AND MECHANICAL SYSTEMSRIG EQUIPMENT THE DERRICKRIG EQUIPMENT ROTATING EQUIPMENTRIG EQUIPMENT THE MUD CIRCULATION PROCESSRIG EQUIPMENT CIRCULATION SYSTEMSlide Number 15RIG EQUIPMENTTHE DRILLSTRINGSlide Number 17Slide Number 18CONTINUING THE DRILLING PROCESSSlide Number 20Slide Number 21Other Drilling ProblemsSlide Number 23Slide Number 24Slide Number 25Slide Number 26Slide Number 27