1. INSTRUCTOR © 2017, John R. Fanchi
All rights reserved. No part of this manual may be reproduced in any form without the express written permission of the author.
© 2004 John R. Fanchi All rights reserved. Do not copy or distribute.

2. To the Instructor
The set of files here are designed to help you prepare lectures for your own course using the text Introduction to Petroleum Engineering, J.R. Fanchi and R.L. Christiansen (Wiley, 2017)
File format is kept simple so that you can customize the files with relative ease using your own style. You will need to supplement the files to complete the presentation topics.

3. ROTARY DRILLING © 2017, John R. Fanchi
All rights reserved. No part of this manual may be reproduced in any form without the express written permission of the author.
© 2004 John R. Fanchi All rights reserved. Do not copy or distribute.

4. Outline Prime Movers Hoisting System Drill String and Bits
Circulating System
Well Control System
Typical Drilling Problems
Pressure Control

5. PRIME MOVERS
© 2004 John R. Fanchi All rights reserved. Do not copy or distribute.

6. Rotary Drilling System
Prime Movers
Hoisting System
Rotating System
Circulating System
Controlling System

7. Purpose of Prime Mover Prime Movers supply rig power Mechanical Rigs
Engines directly hooked up to drawworks, rotary table, pumps, etc.
Normal maintenance & crews

8. Prime Movers Engines Provide Power

9. HOISTING SYSTEM
© 2004 John R. Fanchi All rights reserved. Do not copy or distribute.

10. Hoisting System Derrick or Mast Drawworks
Crown Block
Traveling Block
Hook
Hoisting Line
Drill Floor
Derrick or Mast
Drawworks
Crown Block & Traveling Block
Hook & Swivel
Drilling Line (cable)
Top Drive (newer technology)

11. Hoisting System

12. Finger board under monkey board
Derrick or Mast
Crown Block
Monkey
Board
Traveling
Block
Monkey Board
Finger board under monkey board
Mud Hose
Traveling Block

13. Derrick or Mast V-door Pipe ramp Derrick is raised in sections
Mast is raised as single unit

14. Traveling Block
Hook
Swivel
Kelly

15. Kelly
Kelly Bushing
Rotary Table
Drill Pipe
Swivel

16. DRILL STRING AND BITS
© 2004 John R. Fanchi All rights reserved. Do not copy or distribute.

17. Drill Pipe Drill Collar Joint Joint
Bit
Drawworks
Crown Block
Traveling Block
Hook
Kelly
Rotary Table
Drill Floor
Drillstring
Drill Collar
Drill Pipe
Swivel
Box
connection
Pin
connection
Joint
Joint

18. Insert Tricone Drill Bit
Pin connection
Mud Nozzle or Jet
Leg
Cone with buttons

19. Bit Efficiency: Based Upon Cost Per Foot Drilled
cost/ft drilled decreases as # of ft drilled increases
$/Ft
Bit wearing out
Time to replace bit
Time to drill
Bit Efficiency is a measure of when a bit begins to wear out

20. Weight on Bit Measure WOB using sensors on drill bit
bottom hole assembly (BHA) such as MWD
Limit WOB so bit is not crushed
Bits can withstand approximately 3,000 to 10,000 psi per inch of bit diameter
Typical bit diameters are 3 ¾” to 26”
Many modern drillstrings include downhole motor in BHA
Downhole motor provides more power to bit

21. Stability Map of Typical PDC Bit
Dynamic dysfunction zones
Design WOB and RPM to stay in Stable Zone
Source: SPE (2011, Fig. 1)

22. Torsional Stress Torsion caused by twisting moment (aka torque)
Shear or Torsional Stress
τ = Tr/J
Differential Angle of Twist
dϕ/dz = T/GJ
ϕ = angle of twist
z = length along axis of pipe
T = torque
J = polar moment of inertia
G = shear modulus
τ = shear stress
T = torque
r = outer radius of pipe
J = polar moment of inertia

23. CIRCULATING SYSTEM
© 2004 John R. Fanchi All rights reserved. Do not copy or distribute.

24. Circulating System

25. Mud System Has Many Purposes
Lift cuttings to surface
Control formation pressure
Protect formations
Prevents subsurface fluids (water, gas, oil) from flowing into well
Lubricate
Cool bit

26. Drilling Mud Fresh Water – water-based drilling mud
Diesel Oil – oil-based drilling mud
Synthetic Oil – synthetic-based drilling mud
Additives
Clay – bentonite
Chemicals

27. Drilling Mud Density Component Density Water 8.3 lbs/gal Bentonite Mud
(1 g/cc or 62.4 lb/cu ft)
Bentonite Mud
9 to 10 lbs/gal
Heavy Mud
15 to 20 lbs/gal

28. Drilling Mud Is More Dense than Water
Component
Density
Water
8.3 lbs/gal
(1 g/cc or 62.4 lb/cu ft)
Bentonite Mud
9 to 10 lbs/gal
Heavy Mud
15 to 20 lbs/gal

29. Mud Types – 1
Water based
Oil based
Foam
Mist
Air
Polymer

30. Circulating System

31. Wellbore Failures Related to Mud Weight
Optimum MW
MW = mud weight
PP = pore pressure
SFG = shear failure gradient
FG = fracture gradient
After Zhang, et al, SPE (2008)

32. Preventing Formation Damage
Drill with:
Underbalance pressure
Brine
Oil-based drilling mud
Air

33. Sluffing (or sloughing)
Can occur when mud pressure is inadequate
Heaving: Partial or complete collapse of the walls of a hole
Cave-in: collapse of the walls of the wellbore

34. WELL CONTROL SYSTEM
© 2004 John R. Fanchi All rights reserved. Do not copy or distribute.

35. BOP
BOP
Annular BOP
Blind Shear Ram
Pipe Ram
Kill Line
Casing head

36. TYPICAL DRILLING PROBLEMS

37. Examples of Drilling Problems
Crooked hole
Hole sloughing – cave in
Stuck pipe
Fishing

38. Sloughing (aka sluffing)
Heaving: Partial or complete collapse of the walls of a hole
Cave-in: collapse of the walls of the wellbore
Source:

39. Occurs when compressive load > critical value
Buckling
Tubular deformation
Occurs when compressive load > critical value
Sinusoidal buckling
Tube snaps into sinusoidal shape
aka snaking or lateral buckling
Helical buckling
Tube snaps into helical (spiral) shape

40. Fishing (aka Retrieving)
Fishing Tools

41. PRESSURE CONTROL

42. Possible Issues Abnormal Pressure Kick Formation Damage
e.g. overpressured formation
Kick
high pressure formation fluids flowing into wellbore
HTHP – high temperature & high pressure
Typically >300° F & 10,000 psi
Formation Damage
Poor rig & crew performance
Slow drilling
Logistics

43. Source: http://oilgasglossary.com/
BLOWOUTS
Uncontrolled flow of reservoir fluids
into wellbore
sometimes to surface
Source:

44. Relief Well Dual Strategy Relief Well Event Occurs (e.g. blowout)
Kill Well
Surface Intervention

45. Lose drilling mud, e.g. in high perm formation
Lost Circulation
Lose drilling mud, e.g. in high perm formation

46. Lost Circulation Lake Peigneur, Louisiana
Diagram showing the oil rig disaster is available at
The rig was drilling in a lake above a salt dome.

47. Video Lake Peigneur, LA (Nov. 20, 1980)
Operations at Lake Peigneur
Texaco drilling from surface of lake with 14” drill bit
Diamond Crystal Salt Company mining salt under lake
Jefferson Island salt mine
Major operational problem: flood mine
Rig was drilling in a lake above a salt dome.
 Video of the oil rig disaster in Lake Peigneur, Louisiana:

48. Lake Peigneur Settlement
Texaco and Wilson Brothers paid $44.8 million in settlement
$32 million to Diamond Crystal
$12.8 million to nearby Live Oak Gardens (residential)

49. QUESTIONS?
© 2004 John R. Fanchi All rights reserved. Do not copy or distribute.

50. SUPPLEMENT
© 2004 John R. Fanchi All rights reserved. Do not copy or distribute.