Drilling Engineering – Fall 2012
Drilling Engineering – PE 311
Rotary Drilling System
Prepared by: Tan Nguyen
Drilling Engineering – Fall 2012
General Information
Instructor: Tan Nguyen
Class: Tuesday & Thursday
Time: 11:00 AM - 12:15 PM
Room: WIER 129
Office: MSEC 372
Office Hours: Tuesday & Thursday 2:00 – 4:00 pm
Phone: ext-5483
E-mail: tcnguyen@nmt.edu
Prepared by: Tan Nguyen
Drilling Engineering – Fall 2012
Required Materials
1.
Applied Drilling Engineering – Adam T. Bourgoyne – SPE
Textbook OR
2.
Fundamentals of Drilling Engineering – Robert Mitchell & Stefan
Miska – SPE Textbook.
3.
Class notes
4.
PowerPoint slides
Prepared by: Tan Nguyen
Drilling Engineering – Fall 2012
Grading
Homework: 20%
Quizzes: 20%
Midterm exam: 30%
Final: 30%
Prepared by: Tan Nguyen
Drilling Engineering – Fall 2012
Movie
http://www.youtube.com/watch?v=DniNIvE69SE&feature=relate
d
Prepared by: Tan Nguyen
Drilling Engineering – Fall 2012
Main Rig Components
Prepared by: Tan Nguyen
Drilling Engineering – Fall 2012
Main Rig Components
1. Power System
2. Hoisting System
3. Fluid Circulating System
4. Rotary System
5. Well Control System
6. Well Monitoring System
Prepared by: Tan Nguyen
Drilling Engineering – Fall 2012
Main Topics in Drilling
1.
Rotary drilling
2.
Drilling fluids
3.
Drilling hydraulics
4.
Drilling bits
5.
Directional drilling
6.
Formation and fracture pressure
7.
Cements
8.
Casing design
9.
Tubing design
10.
Other topics: under balance drilling, cutting transport, etc.
Prepared by: Tan Nguyen
Drilling Engineering – Fall 2012
Steps To Drill an Oil/Gas Well
1. Complete or obtain seismic, log, scouting information or other data.
2. Lease the land or obtain concession.
3. Calculate reserves or estimate from best data available.
4. If reserve estimates show payout, proceed with well.
5. Obtain permits from conservation/national authority.
6. Prepare drilling and completion program.
7. Ask for bids on footage, day work, or combination from selected drilling
contractors based on drilling program.
8. If necessary, modify program to fit selected contractor equipment.
Prepared by: Tan Nguyen
Drilling Engineering – Fall 2012
Steps To Drill an Oil/Gas Well
9. Construct road, location/platforms and other marine equipment necessary for
access to site.
10. Gather all personnel concerned for meeting prior to commencing drilling (prespud meeting)
11. If necessary, further modify program.
12. Drill well.
13. Move off contractor if workover unit is to complete the well.
14. Complete well.
15. Install surface facilities.
16. Analysis of operations with concerned personnel.
Prepared by: Tan Nguyen
Drilling Engineering – Fall 2012
Drilling Rig
A drilling rig is a machine which creates holes (usually called boreholes) in the
ground. Drilling rigs can be massive structures housing equipment used to drill
water wells, oil wells, or natural gas wells, or they can be small enough to be
moved manually by one person.
Rotary table drive: rotation is achieved by turning the kelley at the drill floor.
Top drive: rotation and circulation is done at the top of the drill string, on a
motor that moves in a track along the derrick.
Prepared by: Tan Nguyen
Drilling Engineering – Fall 2012
Drilling Rig
Drilling rig preparing rock blasting
Water well drilling rig
Prepared by: Tan Nguyen
Drilling Engineering – Fall 2012
Drilling Rig
Oil drilling rig onshore
Rotary table drive
Prepared by: Tan Nguyen
Oil drilling rig onshore
Top drive
Drilling Engineering – Fall 2012
Drilling Rig
Rotary Table drive Drilling
Prepared by: Tan Nguyen
Top Drive Drilling
Drilling Engineering – Fall 2012
Drilling Rig
An advantage of a top drive is that it allows the drilling rig to drill longer
sections of a stand of drill pipe. A rotary table type rig can only drill 30’
sections of drill pipe while a top drive can drill 90-feet drillpipe. Therefore,
there are fewer connections of drill pipe and hence improving time efficiency.
Prepared by: Tan Nguyen
Drilling Engineering – Fall 2012
Drilling Rig
While the bit cuts the rock at the bottom of the hole, surface pumps are forcing
drilling fluids down the hole through the inside of the drill pipe and out the bit. This
fluid lubricates and removes cuttings. The fluid (with the cuttings) then flows out the
center of the drill bit and is forced back up the outside of the drill pipe onto the
surface of the ground where it is cleaned of debris and pumped back down the hole.
This is an endless cycle that is maintained as long as the drill bit is turning in the
hole.
In generally, there are four main systems of a rotary drilling process including: Rig
power system, hoisting system, drill string components, and circulating system.
Prepared by: Tan Nguyen
Drilling Engineering – Fall 2012
Rig Power System
The power generated by the power system is used principally for five main
operations: (1) rotating, (2) hosting, (3) drilling fluid circulation, (4) rig lighting system,
and (5) hydraulic systems. However, most of the generated power is consumed by
the hoisting and fluid circulation systems. In most cases these two systems are not
used simultaneously, so the same engines can perform both functions.
Rig power system performance characteristics generally are stated in terms of output
hoursepower, torque, and fuel consumption for various engine speeds. The following
equations perform various design calculations:
Prepared by: Tan Nguyen
Drilling Engineering – Fall 2012
Rig Power System
Prepared by: Tan Nguyen
Drilling Engineering – Fall 2012
Rig Power System
P – shaft power developed by engine, hp
(1)
(2)
Qi – heat energy consumed by the engine, hp
Et – overall power system efficiency
w – angular velocity of the shaft, rad/min;
(3)
w = 2pN with N is the shaft speed in RPM
T – output torque, ft-lbf
Wf – volumetric fuel consumption, gal/hour
H – heating value of diesel, 19,000 BTU/lbm
rd – density of diesel, 7.2 lbm/gal
33,000 – conversion factor, ft-lbf/min/hp
Prepared by: Tan Nguyen
Drilling Engineering – Fall 2012
Rig Power System
Prepared by: Tan Nguyen
Fuel
Type
Density
(lbm/gal)
Heating Value
(Btu/lbm)
diesel
7.2
19,000
gasoline
6.6
20,000
butane
4.7
21,000
methane
---
24,000
Drilling Engineering – Fall 2012
Rig Power System
Example 1.1. A diesel engine gives an output torque of 1740 ft-lbf at an engine
speed of 1,200 rpm. If the fuel consumption rate was 31.5 gal/hr, what is the output
power and overall efficiency of the engine.
Solution:
Angular velocity:
w = 2pN = 2p(1200) = 7,539.84 rad/min
The power output:
Heat energy consumed by the engine:
Overal efficiency:
Prepared by: Tan Nguyen
Drilling Engineering – Fall 2012
Hoisting System
The function of the hoisting system is to get the necessary equipment in and out of
the hole as rapidly as is economically possible. The principal items of equipment that
are used in the hole are drillstring, casing, and miscellaneous instruments such as
logging and hole deviation instruments. The major components of the hoisting
system are:
(1) the derrick,
(2) the block and tackle system,
(3) the drawworks,
(4) miscellaneous hoisting equipment such as hooks, elevators, and weight indicator.
Prepared by: Tan Nguyen
Drilling Engineering – Fall 2012
Derrick
The function of the derrick is to provide the vertical height required to raise sections
of pipe from or lower them into the hole. Derricks are rated according to their height
and their ability to withstand compressive and wind loads. The greater the height of
the derrick, the longer the section of pipe that can be handled. The most commonly
used drillpipe is between 27-30 feet. To provide working space below the derrick
floor for pressure control valves called blowout preventer, the derrick usually is
elevated above the ground level by placement on a substructure.
Prepared by: Tan Nguyen
Drilling Engineering – Fall 2012
Making a Trip
http://www.youtube.com/watch?v=5f3STxhzICQ
http://www.osha.gov/SLTC/etools/oilandgas/drilling/trippingout_in.html#
Prepared by: Tan Nguyen
Drilling Engineering – Fall 2012
Making a Trip
Tripping In
Tripping Out
• Setting Slips
• Elevators raised
• Breaking Out and Setting Back the Kelly
• Tripping In -- Latching Elevators to Top of
Stand
• Attaching Elevators to the Elevator Links
• Latching Elevators to Pipe
• Working on the Monkeyboard
• Breaking Out Pipe
• Maneuvering Pipe to Racking Area
• Moving pipe to rotary
• Pipe is made up
• Slips are pulled
• Slips are set
• Elevators are unlatched
• Process repeated for all stands
• Pickup kelly and attach to drill string
• Break circulation, and
• Resume drilling
Prepared by: Tan Nguyen
Drilling Engineering – Fall 2012
Making a Connection / Tripping In
Making a
mouse hole
connection
Prepared by: Tan Nguyen
Drilling Engineering – Fall 2012
Making a Connection / Tripping In
Moving Kelly
to Single in
Mousehole
Prepared by: Tan Nguyen
Stabbing
the Pipe
Single
Added.
Ready
to Drill
Drilling Engineering – Fall 2012
Tripping Out
Put Kelly in
Rathole
Prepared by: Tan Nguyen
Use
Elevators
for
tripping
Drilling Engineering – Fall 2012
Tripping Out
Prepared by: Tan Nguyen
Drilling Engineering – Fall 2012
Block and Tackle
Block and tackle is comprised of the crown block, the travelling block, and the drilling
line. The principal function of the block and tackle is to provide a mechanical
advantage which permits easier handling of large loads.
Prepared by: Tan Nguyen
Drilling Engineering – Fall 2012
Machenical Advantage
The mechanical advantage M of a block and tackle is defined as the ratio of the
load supported by the traveling block, W, and the load imposed on the
drawworks, Ff.
(4)
Prepared by: Tan Nguyen
Drilling Engineering – Fall 2012
Pully
A pulley transfers a force along a rope without changing its magnitude. In Figure a,
there is a force (tension) on the rope that is equal to the weight of the object. This
force or tension is the same all along the rope. For this simple pulley system, the
force is equal to the weight, as shown in the picture. The mechanical advantage of
this system is 1!.
In the Figure b, the pulley is moveable. As the rope is pulled up, it can also move up.
Now the weight is supported by both the rope end attached to the upper bar and the
end held by the person! Each side of the rope is supporting the weight, so each side
carries only half the weight. So the force needed to hold up the pulley in this example
is 1/2 the weight! Now the mechanical advantage of this system is 2.
Prepared by: Tan Nguyen
Drilling Engineering – Fall 2012
Pully
a
Prepared by: Tan Nguyen
b
c
d
Drilling Engineering – Fall 2012
Block and Tackle
Without friction between the block and the tackle, the mechanical advantage is given by
(5)
Equation (1.5) tells us the ideal mechanical advantage is equal to the number of lines.
For frictionless between the block and tackle, the power efficiency is given by
(6)
In general, the power efficiency can be calculated
(7)
Prepared by: Tan Nguyen
Drilling Engineering – Fall 2012
Block and Tackle
The load applied to the derrick, Fd, is the sum of the hook load, W, the tension in the
dead line, Fs, and the tension in the fast line, Ff:
(8)
The total derrick load is not distributed equally over all four derrick legs. Since the
drawworks is located on one side of the derrick floor, the tension in the fast line is
distributed over only two of the four legs. Also, the dead line affects only the leg to which
it is attached. If E > 0.5, the load on leg A is greatest of all four legs. Since if any leg
fails, the entire derrick also fails, it is convenient to define a maximum equivalent derrick
load, Fde, which is equal to four times the maximum leg load.
Prepared by: Tan Nguyen
Drilling Engineering – Fall 2012
Block and Tackle
Maximum equivalent derrick load:
(9)
Prepared by: Tan Nguyen
Drilling Engineering – Fall 2012
Drawworks
The drawworks is a complicated mechanical system with many functions:
1. To lift drill string, casing, or tubing string, or to pull in excess of these string loads to
free stuck pipe.
2. Provide the braking systems on the hoist drum for lowering drill string, casing string,
or tubing string into the borehole.
3. Transmit power from the prime movers to the rotary drive sprocket to drive the rotary
table
4. Transmit power to the catheads for breaking out and making up drill string, casing
and tubing string.
Prepared by: Tan Nguyen
Drilling Engineering – Fall 2012
Drawworks
Prepared by: Tan Nguyen
Drilling Engineering – Fall 2012
Drawworks
Prepared by: Tan Nguyen
Drilling Engineering – Fall 2012
Efficiency Factor, E
The input power to the drawworks is calculated by taking into account the efficiency
of the chain drives and shafts inside the drawworks. The efficiency factor E is given
by the following equation:
Where K is sheave and line efficiency per sheave; K = 0.9615 is in common use.
Prepared by: Tan Nguyen
Drilling Engineering – Fall 2012
Example
Example 1.2: A rig must hoist a load of 300,000 lbf. The drawworks can provide an
input power to the block and tackle system as high as 500 hp. Eight lines are strung
between the crown block and traveling block. Calculate:
1. The static tension in the fast line when upward motion is impending
2. The maximum hook horsepower available.
3. The maximum hoisting speed
4. The actual derrick load
5. The maximum equivalent derrick load
6. The derrick efficiency factor
Prepared by: Tan Nguyen
Drilling Engineering – Fall 2012
Example
1. The static tension in the fast line when upward motion is impending
2. The maximum hook horsepower available.
Ph = Epi = 0.844 x 500 = 420.5 hp
3. The maximum hoisting speed
4. The actual derrick load
5. The maximum equivalent derrick load
6. The derrick efficiency factor
Prepared by: Tan Nguyen