2 Kellifereday Downhole Problems

2012 AAPL ANNUAL MEETING SPONSORSPLATINUM

GOLD

SILVER

SAN FRANCISCO SEMINAR GOLF

A wholly owned subsidiary of ExxonMobil

BRONZE

58th Annual Meeting - San Francisco

June 13-16, 2012

Downhole Drilling Problems:Drilling Mysteries Revealed!

Kelli Fereday, BP

AAPL - Copyright © 2012. All Rights Reserved.

Today’s Goal

Drillers have a term for downhole problems that can not be diagnoosed or understood:

The objective of this session is to turn these mysteries into understandable and solvable opportunities for improvement

AAPL - Copyright © 2012. All Rights Reserved.

Downhole Drilling Problems

• Industry Prevalence• Types of Drilling “Trouble Time” • Impact on Well Safety, Time, and Cost• Causes and Diagnosis of Drilling Problems• Examples and Remedies for Common Problems

– Downhole Failures– Stuck Pipe– Lost Circulation– Wellbore Stability– Well Control– Q&A

AAPL - Copyright © 2012. All Rights Reserved.

Typical Drilling Time Breakdown

Productive Time50%Non-Productive

Time25%

Invisible Lost Time25%

“Making Hole!Inefficient

Drilling Problems

Impact on the Industry• Biggest Impact - HSE

– Many drilling problems are also associated with increased risk to personnel

Example: Stuck Pipe May Require Jarring which can lead to dropped

objects

Example: Lost Circulation may lead to Lost of Well Control, resulting in

potential Damage to the Environment, Fire and/or Harm to Personnel

Impact on the Industry• Efficiency

– Estimates are as much as 10-40% (25% on average) of drilling time is non-productive time!

– US Rig Count ~1980 rigs, projected need by 2017 is 2500, or approximately a 25% increase

– Imagine being able to close that gap through improvements in drilling performance alone.

– US E&P Budget is about $170BB annually - > $$$

Baker Hughes Rig Countwww.bakerhughes.com

How do we diagnose NPT?• Drilling Reports

– Rig Morning Reports– Mud Reports– Cuttings Analysis

• Downhole and Surface

Measurements• Benchmarking

Sources of NPT – Deepwater Industry Example

DownholeProblems

EquipmentProblems

Top Sources of Downhole Problems

1. Downhole Equipment Failures

2. Downhole Cement Problems

3. Stuck Pipe

4. Lost Circulation

5. Wellbore Stability

6. Well Control

Likely Related

to Geology

Downhole Equipment Failures

• A single equipment failure can– Compromise the integrity of the well– Cost Millions of Dollars to Repair

• Common Equipment Failures– Casing– Drillpipe– Downhole Motors– Downhole Measurement Tools

• MWD• LWD

Vector Motorswww.nov.com

Downhole Cement Problems• Cement Left in Pipe

– Premature Setting– Surface Equipment Pump

Failures

• Cement Not Setting Properly– Cement never sets – “Bad

Shoe” or “No Shoe Test”– Cement allows for gas

migration– Cement seeps away into faults

or fractures – “Partial or Total Losses”

Picture from Halliburton website:

generic example of a cemented wellbore

Stuck Pipe

1. Differential Sticking– Pressure-related – The pipe is “sucked” up against the

formation due to a difference in pressure

2. Mechanical Sticking– A mechanical obstruction– Could be from the formation, wellbore

geometry, or tool failure

Differential Sticking – A Pressure Problem

Mechanical Sticking – Dirty Wellbore

• Too many “solids” in the wellbore!– Indications:

• higher pump pressure• fill on bottom• more “pull” required to move pipe• excessive cuttings on shakers• restricted circulation

• Why?– Unconsolidated Formations– Poor Hole Cleaning

• Prevention– maximise flow rates and rpm– Better mud properties– drill more slowly

Formations Fall in on the pipe!

Mechanical Sticking – Obstructions

• Obstructions– Indications:

• more “pull” required to move pipe• can still circulate• Increased torque• Unable to “make hole”

• Why?– Junk in the Wellbore– Hole Geometry

• Prevention– equipment QA/QC– housekeeping– correct drillstring/BHA design

Tool Failures or Junk in Hole

Doglegs or Underguage Hole

Stuck Pipe – How do we get free?

• Pull Harder (but don’t break it)• Jar on Pipe• Cut Pipe and Fish• Increase or decrease circulation• Pump other types of fluids or

chemicals

Lost Circulation• Conventional drilling utilizes

continuous fluid flow down the drillpipe to:– Remove cuttings– Maintain pressure– Cool the bit

• Key indicator in understanding what is happening downhole

• Circulation must be maintained at all times

• If the circulation is interrupted because fluid is flowing into the formation, that is called “Lost Circulation”

Lost Circulation - Causes

Induced

Natural

Lost Circulation - Solutions

Prevention

LCM

Wellbore Stability

• An unstable wellbore can result in:– Stuck Pipe– Lost Circulation– Loss of the entire wellbore

• 2 Main causes are:– Chemical Instability

• Reactive Formations– Mechanical failure of wellbore

• Faults• Insufficient Mud Weight

Well Control• Well Control means the ability to keep the hydrocarbons where

they belong at all times – in the ground.• Common terms

– “Taking a Kick”– Blowout

• Most dangerous downhole problem

Well Control• What causes loss of well control?

– Multiple Barrier Failures

• Equipment Failures• Loss of fluid pressure in the pipe

counteracting the natural pressure existing in the formation

• Industry Methods dealing with Well Control– Wellbore Monitoring– Well Kill Methods - how to safely remove

hydrocarbons from the wellbore• Circulating Methods• Non-circulating Methods

Mud BOP

Pre

ssu

re

Industry Challenges• The Great Crew Change

• Well Complexity

2000 2006 2012203040506070

43 50 60

Peak Age of Petroleum Engineers

Pete Stark, VP of industry relations for IHS

Technology Game-Changers

• Rig Automation• Advanced Downhole Tools• Real-time montioring• Managed Pressure Drilling• Simulators for Training

www.weatherford.com

Q&A