2. 1.
Introduction
2.
Types of rigs
3.
Personnel at Rig Site
4.
How to drill a well
3.
4. 2 drilling goals
to build the well according to its purpose and in a safe manner
(i.e, avoiding personal injuries
and avoiding technical problems)
to complete it with minimum cost
Thereto the overall costs of the well during its lifetime in conjunction with the field development aspects shall be minimized. Fall 14 H. AlamiNia Drilling Engineering 1 Course (3rd Ed.) 4
5. Parameters
The overall cost minimization, or optimization, may influence
the location from where the well is drilled,
(e.g., an extended reach onshore or above reservoir offshore),
the drilling technology applied,
(e.g., conventional or slim–hole drilling, overbalanced or underbalanced, vertical or horizontal, etc),
and which evaluation procedures are run to gather subsurface information to optimize future wells.
Fall 14 H. AlamiNia Drilling Engineering 1 Course (3rd Ed.) 5
6. drilling technologies
To build a hole, different drilling technologies have been invented:
Percussion drilling
Cable drilling “Pennsylvanian drilling”
Drillstring
•
With mud Quick percussion drilling
•
Without mud “Canadian drilling”
Rotating drilling (Will be discussed exclusively)
Full cross-section drilling
•
Surface driven
o
Rotary bit
o
Rotary nozzle
•
Subsurface driven
o
Turbine drilling
o
Positive displacement motor drilling
o
Electro motor drilling
Annular drilling
•
Diamond coring
•
Shot drilling
Fall 14 H. AlamiNia Drilling Engineering 1 Course (3rd Ed.) 6
7. drilling technologies (Cont.)
Special techniques
Abrasive jet drilling
Cavitating jet drilling
Electric arc and plasma drilling
Electric beam drilling
Electric disintegration drilling
Explosive drilling
Flame jet drilling
Implosion drilling
Laser drilling
REAM drilling
Replaceable cutterhead drilling
Rocket exhaust drilling
Spark drilling
Subterrene drilling
Terra drilling
Thermal-mechanical drilling
Thermocorer drilling
Fall 14 H. AlamiNia Drilling Engineering 1 Course (3rd Ed.) 7
8.
9. drilling rig
A drilling rig is a device used to drill, case and cement oil and gas wells.
The correct procedure for selecting and sizing a drilling rig is as follows:
Design the well
Establish the various loads to be expected during drilling and testing operations and use the highest loads. This point establishes the DEPTH RATING OF THE RIG.
Compare the rating of existing rigs with the design loads
Select the appropriate rig and its components.
Fall 14 H. AlamiNia Drilling Engineering 1 Course (3rd Ed.) 9
10. Rig Classification
Rotary Drilling Rigs
Land
Mobile
Jackknife
Portable Mast
Conventional
Marine
Bottom Supported
Platform
Self Contained
Tendered
Barge
Jack-Up
Submersible
Floating
Drill Ship
Semi Submersible
Caisson Vessel
Tension Leg
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11. Land: Mobile Rigs
Jackknife rig
Portable mast
Fall 14 H. AlamiNia Drilling Engineering 1 Course (3rd Ed.) 11
12. Marine: Bottom Supported Platform rigs
Self Contained
Tendered
Fall 14 H. AlamiNia Drilling Engineering 1 Course (3rd Ed.) 12
13. Marine: Other Bottom Supported rigs
Fall 14 H. AlamiNia Drilling Engineering 1 Course (3rd Ed.) 13
A Jack–Up rig A submersible platform
A cantilever rig on a barge
14. Marine: Floating rigs
Fall 14 H. AlamiNia Drilling Engineering 1 Course (3rd Ed.) 14
Caisson vessel
(also called
sparbuoy) and
Diagram of a
spar–buoy
A tension–
leg platform
A drill–ship
Semi– submersible vessel
15. comparison of drilling rigs
Fall 14 H. AlamiNia Drilling Engineering 1 Course (3rd Ed.) 15
16. Well Classifications
According to a wells final depth, it can be classified into:
Shallow well: < 2000m
Conventional well: 2 000m –3500m
Deep well: 3500m –5000m
Ultra deep well: > 5 000m
With the help of advanced technologies in MWD/LWD and extended reach drilling techniques, horizontal departures of more than10000m are possible today.
Fall 14 H. AlamiNia Drilling Engineering 1 Course (3rd Ed.) 16
17.
18. Personnel
People directly involved in drilling a well are employed either by
the operating company,
the drilling contractor,
or one of the service and supply companies
The operating company is the owner of the lease/block and principal user of the services provided by the drilling contractor and the different service companies.
Fall 14 H. AlamiNia Drilling Engineering 1 Course (3rd Ed.) 18
19. Tasks
Since drilling contractors are companies that perform the actual drilling of the well, their main job is to drill a hole to the depth/location and specifications set by the operator.
Along with hiring a drilling contractor, the operator usually employs various service and supply companies to perform
logging,
cementing,
or any other special operations, including maintaining the drilling fluid in its planed condition.
Fall 14 H. AlamiNia Drilling Engineering 1 Course (3rd Ed.) 19
20. drilling crews
Most drilling crews consist of
a tool pusher,
a driller,
a derrickman,
a mud logger,
and two or three rotary helpers
(also called floormen or roughnecks).
Along with this basic crew configuration the operator sends usually a representative, called
company man to the rig.
For offshore operations the crews usually consist of many more employees.
Fall 14 H. AlamiNia Drilling Engineering 1 Course (3rd Ed.) 20
21. crew requirements
Tool Pusher:
supervises all drilling operations and is the leading man of the drilling contractor on location.
Company Man:
The company man is in direct charge of all company’s activities on the rig site.
He is responsible for the drilling strategy as well as the supplies and services in need. His decisions directly effect the progress of the well.
Fall 14 H. AlamiNia Drilling Engineering 1 Course (3rd Ed.) 21
22. crew requirements (Cont.)
Driller:
The driller operates the drilling machinery on the rig floor and is the overall supervisor of all floormen.
He reports directly to the tool pusher and is the person who is most closely involved in the drilling process.
He operates, from his position at the control console, the rig floor brakes, switches, levers, and all other related controls that influence the drilling parameters.
In case of a kick he is the first person to take action by moving the bit off bottom and closing the BOP.
Fall 14 H. AlamiNia Drilling Engineering 1 Course (3rd Ed.) 22
23. Inside a control console
Fall 14 H. AlamiNia Drilling Engineering 1 Course (3rd Ed.) 23
24. crew requirements (Cont.)
Derrick Man:
The derrickman works on the so– called monkeyboard, a small platform up in the derrick, usually about 90 ft above the rotary table.
When a connection is made or during tripping operations he is handling and guiding the upper end of the pipe.
During drilling operations the derrickman is responsible for maintaining and repairing the pumps and other equipment as well as keeping tabs on the drilling fluid.
Fall 14 H. AlamiNia Drilling Engineering 1 Course (3rd Ed.) 24
25. crew requirements (Cont.)
Floormen:
During tripping, the rotary helpers are responsible for handling the lower end of the drill pipe as well as operating tongs and wrenches to make or break up a connection.
During other times, they also maintain equipment, keep it clean, do painting and in general help where ever help is needed.
Mud Engineer, Mud Logger:
The service company who provides the mud almost always sends a mud engineer and a mud logger to the rig site. They are constantly responsible for logging what is happening in the hole as well as maintaining the proper mud conditions.
Fall 14 H. AlamiNia Drilling Engineering 1 Course (3rd Ed.) 25
26.
27. drilling process
In rotary drilling, the rock is destroyed by the action of rotation and axial force applied to a drilling bit.
The drilling bit is located at the end of a drill string which is composed of drill pipes (also called joints or singles), drill collars, and other specialized drilling tools.
Drill collars are thick walled tubes responsible for applying the axial force at the bit.
Rotation at the bit is usually obtained by rotating the whole drill string from the surface.
Fall 14 H. AlamiNia Drilling Engineering 1 Course (3rd Ed.) 27
28. A simplified drillstring
The components of the drillstring are:
Drillpipe
Drillcollars
Other Accessories called bottom hole assembly (BHA) including:
Heavy-walled drillpipe (HWDP)
Stabilisers
Reamers
Directional control equipment
Etc. Fall 14 H. AlamiNia Drilling Engineering 1 Course (3rd Ed.) 28
29. Functions of the drillstring
The drill string is the mechanical linkage connecting the drillbit at the bottom of the hole to the rotary drive system on the surface.
The drillstring serves the following functions:
transmits rotation to the drillbit
exerts weight on the bit;
the compressive force necessary to break the rock
guides and controls the trajectory of the bit; and
allows fluid circulation
which is required for cooling the bit and for cleaning the hole. Fall 14 H. AlamiNia Drilling Engineering 1 Course (3rd Ed.) 29
30. drilling process (Cont.)
A large variety of bit models and designs are available in industry.
The choice of the right bit, based on the characteristics of the formations to be drilled, and the right parameters (weight on bit and rotary speed)
are the two most basic problems the drilling engineer faces during drilling planning and drilling operation.
The cuttings are lifted to the surface by the drilling fluid.
At the surface, the cuttings are separated from the drilling fluid by several solid removal equipment.
Drilling mud is picked up by the system of pumps and pumped again down the hole.
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31. connection
As drilling progresses, new joints are added to the top of the drill string increasing its length, in an operation called connection.
A pipe slips is used to transfer the weight of the drillstring from the hook to the master bushing. Fall 14 H. AlamiNia Drilling Engineering 1 Course (3rd Ed.) 31
32. round trip
As the bit gets dull, a round trip is performed to bring the dull bit to the surface and replace it by a new one.
A round trip is performed also to change the BHA.
The drillstring is also removed to run a casing string. The operation is done by removing stands of two (“doubles”), three (“thribbles”) or even four (“fourbles”) joints connected, and stacking them upright in the rig.
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33. Removing one stand of drillstring
Fall 14 H. AlamiNia Drilling Engineering 1 Course (3rd Ed.) 33
34. wiper trip
Sometimes the drillstring is not completely run out of the hole.
It is just lifted up to the top of the open-hole section and then lowered back again while continuously circulating with drilling mud.
Such a trip, called wiper trip,
is carried out to clean the hole from remaining cuttings that may have settled along the open–hole section.
Fall 14 H. AlamiNia Drilling Engineering 1 Course (3rd Ed.) 34
35. 1.(CDF) Jorge H.B. Sampaio Jr. “Drilling Engineering Fundamentals.” Master of Petroleum Engineering. Curtin University of Technology, 2007.
Chapter 1 and 2
2.(WEC) Rabia, Hussain. Well Engineering & Construction. Entrac Consulting Limited, 2002.
Chapter 16