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Drilling Engineering 1 Course (2nd Ed.)
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 costThereto the overall costs of the well during its lifetime in
conjunction with the field development aspects shall be minimized.
Spring14 H. AlamiNia Drilling Engineering 1 Course (2nd Ed.) 4
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.
Spring14 H. AlamiNia Drilling Engineering 1 Course (2nd Ed.) 5
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 driveno Rotary bito Rotary nozzle
• Subsurface driveno Turbine drillingo Positive displacement motor drillingo Electro motor drilling
Annular drilling Diamond coring Shot drilling
Spring14 H. AlamiNia Drilling Engineering 1 Course (2nd Ed.) 6
drilling technologies (Cont.)
Special techniquesAbrasive 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
Spring14 H. AlamiNia Drilling Engineering 1 Course (2nd Ed.) 7
Rig Classification
Rotary Drilling Rigs
Land
Mobile
JackknifePortable
Mast
Conventional
Marine
Bottom Supported
Platform
Self Contained
Tendered
Barge
Jack-Up Submersible
Floating
Drill ShipSemi
Submersible
Caisson Vessel
Tension Leg
Spring14 H. AlamiNia Drilling Engineering 1 Course (2nd Ed.) 8
Land: Mobile Rigs
Jackknife rig Portable mastSpring14 H. AlamiNia Drilling Engineering 1 Course (2nd Ed.) 9
Marine: Bottom Supported Platform rigs
Self Contained TenderedSpring14 H. AlamiNia Drilling Engineering 1 Course (2nd Ed.) 10
Marine: Other Bottom Supported rigs
Spring14 H. AlamiNia Drilling Engineering 1 Course (2nd Ed.) 11
A Jack–Up rig A submersible platform
A cantilever rig on a barge
Marine: Floating rigs
Spring14 H. AlamiNia Drilling Engineering 1 Course (2nd Ed.) 12
Caisson vessel
(also called
sparbuoy) and Diagram of a spar–buoy
A tension–
leg platform
A drill–ship Semi–
submersible
vessel
Personnels
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.
Spring14 H. AlamiNia Drilling Engineering 1 Course (2nd Ed.) 14
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.
Spring14 H. AlamiNia Drilling Engineering 1 Course (2nd Ed.) 15
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, calledcompany man to the rig.
For offshore operations the crews usually consist of many more employees.
Spring14 H. AlamiNia Drilling Engineering 1 Course (2nd Ed.) 16
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.
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.
Spring14 H. AlamiNia Drilling Engineering 1 Course (2nd Ed.) 17
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.
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.
Spring14 H. AlamiNia Drilling Engineering 1 Course (2nd Ed.) 18
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.
Spring14 H. AlamiNia Drilling Engineering 1 Course (2nd Ed.) 19
rig systems
For all rigs, the depth of the planned well determines basic rig requirements. The most important rig systems are:Power system,
Hoisting system,
Drilling fluid circulation system,
Rotary system,
Derrick and substructure,
Well control system,
Well monitoring system
Spring14 H. AlamiNia Drilling Engineering 1 Course (2nd Ed.) 23
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.
Spring14 H. AlamiNia Drilling Engineering 1 Course (2nd Ed.) 24
A simplified drillstring
The lower portion of the drill string, composed of drill collars
and specialized drilling tools,
are called bottom hole assembly (BHA).
Spring14 H. AlamiNia Drilling Engineering 1 Course (2nd Ed.) 25
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.
Spring14 H. AlamiNia Drilling Engineering 1 Course (2nd Ed.) 26
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.
Spring14 H. AlamiNia Drilling Engineering 1 Course (2nd Ed.) 27
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.
Spring14 H. AlamiNia Drilling Engineering 1 Course (2nd Ed.) 28
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.
Spring14 H. AlamiNia Drilling Engineering 1 Course (2nd Ed.) 30
1. Jorge H.B. Sampaio Jr. “Drilling Engineering Fundamentals.” Master of Petroleum Engineering. Curtin University of Technology, 2007. Chapter 1 and 2
1. Power System
2. Hoisting System:A. Introduction
B. The Block & Tacklea. Mechanical advantage and Efficiency