CHAPTER 4 DRILLING OPERATIONS: AN OVERVIEW

• Jurisdiction: United States

Basic Oil & Gas Geology And Technology For Lawyers And Other Non-Technical Personnel
(2001)
CHAPTER 4
DRILLING OPERATIONS: AN OVERVIEW
Ramona M. Graves
Petroleum Engineering Department Colorado School of Mines
Golden, Colorado

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WELLS DRILLED IN THE UNITED STATES

From DeGolyer and MacNaughton, December 2000

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ESTIMATED COST OF DRILLING AND EQUIPPING OIL WELLS IN THE UNITED STATES

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ESTIMATED COST OF DRILLING AND EQUIPPING TOTAL WELLS IN THE UNITED STATES

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DEPTH INTERVAL OF WELLS DRILLED IN THE UNITED STATES IN 1999 (Percentage)

[Page 4-5]

How to Drill a Well — Part 1

• Determine location	• Move in rig up (MIRU) drilling rig
— Geology	— Rigs are portable
— Legal	— Assembly
— Economic	• Drilling
• Prepare site	— Keep a sharp bit on bottom
— Survey	— Add joints every 30 feet
— Clear	— Tripping
— Level	— Use mud
— Water source	• Liquid
— Reserve pit	— Oil
— Roads	— Water
— Reclamation	• Pneumatic
— Dig cellar	— Air
— Dig rat hole and mouse hole	— Natural gas
— Set conductor pipe	— Nitrogen
• Drill surface hole

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How to Drill a Well — Part 2

• Run surface pipe	• Trouble
— Protect fresh water	— Kicks and blow-outs
— Anchor BOPE	— Lost circulation
• Cement surface pipe	— Stuck pipe
— WOC	— Fishing
— Nipple up BOPE	— Mechanical breakdown
• Drill out of surface pipe	— Lost hole
— Leak off test	• Run intermediate casing
• Drill ahead (turn to the right)	— Protects hole
• Evaluation while drilling	• Sloughing
— Mud logging	• High pressure
— Coring	• Low pressure
— MWD	• Salt
Drill stem tests (DST)	• Cement intermedia
• Drill out of interme??

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How to Drill a Well — Part 3

• Drill ahead	• If a keeper
• Reach total depth (TD)	— Run production casing
• Evaluate	— A liner is casing that doesn't reach
— Logging	the surface.
• Electrical	— Cement
• Acoustical	• If a dry hole
• Radioactive	— Plug and abandon as per regulatory
— DST	requirement and prudent operators
• Three things can happen	procedures
— Production is found	• Rig down move out (RDMO)
— Dry hole	drilling rig
— Learned science

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Rig Equipment

• Power	• Rotary Table
— Motors	• Drill String
— Compound	— Swivel and Kelly
• Hoisting	— Drill Pipe
— Drawworks	— Bottom Hole Assembly
— Blocks and Tackle	— Bit
— Mast	• Well Control
— Substructure	— Blow-out Prevention Equipment
• Circulation System	• Ancillary
— Mud Pumps	— Instruments and Doghouse
— Capacity
— Solids Control System

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Power — Motors

• Power

— Hoisting — Drawworks

— Fluid Circulation — Mud Pumps

— Rotary Table

— Other

• Miscellaneous pumps

• Lights

• Television sets

• Coffee pots

• Types

— Diesel — electric

— Diesel — direct drive

— Steam

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Circulation System — Solids Control System

• Solids can be...