PETE 625 Well Control

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PETE 625Well Control

• Lesson 1
• Introduction

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Contents

• Introduction to course
• Basic Concepts
• Liquid Hydrostatics
• Multimedia Lesson 2. Well Control
• Network Places - juvkam-wold2 multimedia
  Lesson 2
• Read Watson, Chap. 1

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Catalog Description

• PETE 625. Well Control. (3.0). Credit 3.
• Theory of pressure control in drilling
  operations and during well kicks abnormal
  pressure detection and fracture gradient
  determination casing setting depth selection and
  advanced casing design theory supplemented on
  well control simulators.
• Prerequisite PETE 411

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Textbook

• Advanced Well Control, by David
• Watson, Terry Brittenham and Preston
• Moore. SPE Textbook Series, 2003
• Class Notes and Homework Assignments can be
  found at
• http//pumpjack.tamu.edu/schubert

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References Well Control

• Kicks and Blowout Control, by Neal Adams and
  Larry Kuhlman. 2nd Editions. PennWell Publishing
  Company, Tulsa, OK, 1994.
• Blowout Prevention, by W.C. Goins, Jr. and Riley
  Sheffield. Practical Drilling Technology, Volume
  1, 2nd Edition. Gulf Publishing Company, Houston,
  1983.
• Advanced Blowout and Well Control, by Robert D.
  Grace. Gulf Publishing Company, Houston, 1994.
• IADC Deepwater Well Control Guidelines, Published
  by the International Association of Drilling
  Contractors, Houston, TX, 1998.
• Guide to Blowout Prevention, WCS Well Control
  School, Harvey, LA, 2000.

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References - General

• Applied Drilling Engineering, by Adam T.
  Bourgoyne Jr., Martin E. Chenevert, Keith K.
  Millheim and F.S. Young Jr., Society of Petroleum
  Engineers, Richardson, TX, 1991.
• Drilling Engineering, A complete Well Planning
  Approach, by Neal Adams and Tommie Carrier.
  PennWell Publishing Company, Tulsa, OK, 1985
• Practical Well Planning and Drilling Manual, by
  Steve Devereux. PennWell Publishing Company,
  Tulsa, OK, 1998.

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Grading

• Homework 20
• Quiz A 20
• Quiz B 20
• Project 20
• Quiz C 20
• See Next Slide for Details

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Important Dates (tentative)

• QUIZ A - Week of October 11
• QUIZ B - Week of November 29
• Project Presentations Week of November 29
• Quiz C - When ever WCS simulator is complete

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Your Instructor

• Name Jerome J. Schubert
• Office 501K Richardson
• Phone [phone]
• e-mail jschubert_at_tamu.edu
• Office Hours TR 1000 1130 am

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Schedule

• Week 1 Introduction, Gas Behavior, Fluid
  Hydrostactics (Ch. 1)
• Weeks 23 Pore Pressure (Ch. 2)
• Weeks 45 Fracture Pressure (Ch. 3)
• Week 6 SPE ATCE - Houston
• Weeks 78 Kick Detection
• and Control Methods (Ch. 4)
• Week 9 Well Control Complications, Special
  Applications (Ch. 56)

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Schedule contd

• Week 10 Well Control Equipment (Ch. 7)
• Week 11 Offshore Operations (Ch. 8)
• Week 12 Snubbing Stripping (Ch. 9)
• Week 13 Blowout Control (Ch. 10)
• Week 14 Casing Seat Selection (Ch. 11)
• Circ. Press. Losses (Appendix A)
• Surge Swab Press. (Appendix B)
• Week 15 Project Presentations

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Definitions

• What is a Kick?
• An unscheduled entry of formation fluids into the
  wellbore of sufficient quantity to require
  shutting in the well
• What is a Blowout?
• Loss of control of a kick

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Why does a kick occur?

• Pressure in the wellbore is less than the
  pressure in the formation
• Permeability of the formation is great enough to
  allow flow
• A fluid that can flow is present in the formation

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How do we prevent kicks?

• We must maintain the pressure in the wellbore
  greater than formation pressure
• But,
• We must not allow the pressure in the wellbore to
  exceed the fracture pressure
• This is done by controlling the HSP of the
  drilling fluid, and isolating weak formations
  with casing

HSP HydroStatic Pressure
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Hydrostatic Pressure, HSP

• HSP 0.052 MW TVD
• HSP Hydrostatic Pressure, psi
• MW Mud Weight (density), ppg
• TVD Total Vertical Depth, ft

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HSP
10 ppg mud
TVD
HSP HSP HSP
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Problem 1

• Derive the HSP equation
• Calculate the HSP for each of the following
• 10,000 ft of 12.0 ppg mud
• 12,000 ft of 10.5 ppg mud
• 15,000 ft of 15.0 ppg mud

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Solution to Problem 1

• Consider a column of fluid
• Cross-sectional area 1 sq.ft.
• Height TVD ft
• Density MW
• Weight of the fluid Vol Density
• 1 1 TVD ft3 62.4 lb/ ft3 MW
  ppg/8.33
• 62.4 / 8.33 MW TVD

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Solution, cont.

• This weight is equally distributed over an area
  of 1 sq.ft. or 144 sq.in.
• Therefore,
• Pressure Weight / area
• 62.4 MW TVD/(8.33144)
• HSP 0.052 MW TVD

W
F PA
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Solution, cont.

• HSP 0.052 MW TVD
• HSP1 0.052 12 10,000 6,240 psi
• HSP2 0.052 10.5 12,000 6,552 psi
• HSP3 0.052 15.0 15,000 11,700 psi

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Terminology

• Pressure
• Pressure gradient
• Formation pressure (Pore)
• Overburden pressure
• Fracture pressure
• Pump pressure (system pressure loss)

• SPP, KRP, Slow circulating pressure, kill rate
  pressure
• Surge swab pressure
• SIDPP SICP
• BHP

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U-Tube Concept
400
400
600
600
Mud HSP 4,800 psi
HSP 5,200 psi
HSP 5,200 psi
Mud HSP 4,800 psi
Influx HSP 200 psi
Influx HSP 200 psi
5,600
5,600
5,600
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More Terminology

• Capacity of
• casing
• hole
• drillpipe
• Annular capacity
• Displacement of
• Drillpipe
• Drill collars

• Rig Pumps
• Duplex pump
• Triplex pump
• KWM, kill weight mud
• Fluid Weight up

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Problem 2

• Calculate the mud gradient for 15.0 ppg mud
• G15 0.052 MW 0.052 15 0.780
  psi/ft
• Calculate the HSP of 15,000 of 15 ppg mud
• HSP 0.780 15,000 11,700 psi

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Problem 3

• The top 6,000 ft in a wellbore is filled with
  fresh water, the next 8,000 with 11 ppg mud, and
  the bottom 16,000 ft is filled with 16 ppg mud.
• (i) What is the BHP?
• (ii) What is the pressure 1/2 way to bottom?
• (iii) Plot the mud density vs. depth
• (iv) Plot the mud gradient vs. depth
• (v) Plot the pressure vs. depth

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Problem 3 solution

• (i) BHP 0.052 (8.33 6,000) (11
  8,000) (16 16,000)
• 20,487 psi
• (ii) Pressure 1/2 way down (at 15,000 ft)
  0.052 (8.33 6,000)
• (11 8,000) (16 1,000)
• 8,007 psi

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Problem 3 solution
Mud Density, ppg

• (iii) Plot MW vs. Depth

0 5 10 15 20
0 5,000 10,000 15,000 20,000 25,000 30,000
8.33 11.0 16.0
Depth
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Problem 3 solution
Mud Gradient, psi/ft

• (iv) Plot mud gradient vs. Depth
• Depth Gradient
• ft psi/ft
• 0-6,000 0.433
• 6,000-14,000 0.572
• 14,000-TD 0.832

0 0.2 0.4 0.6 0.8 0.9
0 5,000 10,000 15,000 20,000 25,000 30,000
0.433 0.572 0.832
Depth
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Problem 3 solution
Mud Pressure, kpsi
0 5,000 10,000 15,000 20,000 25,000 30,000

• (iv) Plot HSP vs. Depth
• ft psi
• _at_ 6,000 2,599
• _at_14,000 7,175
• _at_ 30,000 20,487

8 5 10 15 20
2,599 psi 7,175
psi 20,487 psi
Depth
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Addition of Weight Material

• The amount of barite
• required to raise the
• density of one barrel
• of mud from MW1 to
• MW2, ppg

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Problem 4, Derive Barite Eq.

• Consider one bbl of mud of density, MW1, add WB
  lbs of barite to increase the mud density to MW2.
• Wt, lb Vol, bbl
• Old Mud 42 MW1 1
• Barite WB (WB lbs / 1,490 lb/bbl)
• Mixture WB 42 MW1 1 (WB / 1,490)
• Density of Mixture total weight / total volume

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Problem 4

• New Density Weight / Volume
• MW2 (WB42 MW1 lbs) / 1(WB/1,490)bbl42
  gal/bbl
• 42 MW2 1(WB/1,490) WB42 MW1 lbs
• WB (MW2 / 35.4) -1 42 MW1 42 MW2
• WB(MW2 - 35.4) (42 35.4) (MW1 - MW2)

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Stopping an Influx

• Increase Pressure at Surface
• Increase Annular Friction
• Increase Mud Weight

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Stopping an Influx
Mud Hydrostatic Pressure
Depth
Pressure
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Stopping an Influx Soln.1
Depth
Mud Hydrostatic Pressure
Pressure
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Stopping an Influx Soln.2
Depth
Mud Hydrostatic Pressure
Pressure
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Stopping an Influx Soln.3
Depth
Mud Hydrostatic Pressure
Pressure