50495081 Basic Well Control

1

IDPT Basic WCIPM

Well Engineering ModuleBasic Well Control

IPM IDPT

IDPT Basic WCIPM

• Module Contents

• Objectives and Introduction

• Well Control Fundamentals CD (Self Study)

• WC Incident root causes and IPM Standards

• Primary, Secondary and Tertiary Well Control

• Well Control Mathematics and the “U” Tube

• Kick Causes and Prevention

• Well Control Equipment (HP, LP, BOP, Accumulator, MGS)

• Shut In and Well Kill procedures

• Well Control reporting (Kick reporting, Kill Sheets, etc..)

Basic Well Control

2

IDPT Basic WCIPM

• Module Objectives

• At the end of this lecture and completion of the WCF CD YOU will be able to:

• Define the terms “kick” and “Blowout”

• Perform basic Well Control calculations

• Understand the causes of Well Control incidents

• State primary, secondary and tertiary Well Control procedures

• Understand Well Control Equipment

• Describe the Shut In and Kill methods

• Explain the reporting procedures for Well Control incidents

Basic Well Control

IDPT Basic WCIPM

“A catastrophic well control incident could

put IPM out of business”

- Antonio J. CampoIPM President

3

IDPT Basic WCIPM

• Introduction

• In simple terms, a kick can only occur when the formation pressure exceeds the mud hydrostatic pressure

• The resultant positive differential pressure is transferred intothe wellbore and there is an influx of formation fluids

• If the well is shut in after determining that a kick has occurred then the well can be killed under controlled conditions

• Blow-outs occur when the kick (influx) can not be controlled and there is an emission of wellbore and/or formation fluids at surface

• The rig crew must be fully trained and alert at all times in order to take immediate action to bring the well under control.

Basic Well Control

IDPT Basic WCIPM

• An uncontrolled Kick !

Basic Well Control

Workover RigLand WellRussia

Cause: >Proper equipment not deployed>Poor practices>Lack of training

4

IDPT Basic WCIPM

Basic Well ControlCan turn into this:

Or this:

IDPT Basic WCIPM

Well Control Incidents - Root Causes

• Lack of knowledge and skills of rig personnel• Improper work practices• Lack of understanding of Well Control from certification

training• Lack of application of policies and standards • Poor contractor & supplier management• Inadequate Risk Management & Management of

Change

5

IDPT Basic WCIPM

IPM StandardsStandards

3 HSE4 Quality28 Engineering

IDPT Basic WCIPM

IPM StandardsReference Title InTouch #

IPM-PO-QAS-001 Corporate QHSE Policy 3286066IPM-PO-QAS-002 Engineering Policy 3286067IPM-ST-QAS-001 Document Formatting Standard 3274817IPM-ST-QAS-002 Project Bridging Document 3286070IPM-ST-QAS-003 Glossary of QHSE Definitions 3286072IPM-ST-QAS-004 Management of Change 3286073IPM-PR-QAS-001 Document Numbering and Control Procedure 3274819IPM-FO-QAS-001 Management of Change Form 3286075IPM-CORP-S004 Indemnity and Risk 3286076IPM-ST-HSE-001 Gas Detection Service and Equipment 3286077IPM-ST-HSE-002 Life Saving and Evacuation Equipment 3286078IPM-ST-HSE-003 Simultaneous Operations 3286079IPM-PR-HSE-004 Hygiene in Camps and Accommodations 3286082IPM-PR-HSE-005 Preparation of a Simultaneous Operations Manual 3286083IPM-ST-WCI-001 Well Engineering Management System (WEMS) 3286084IPM-ST-WCI-002 Information to be Kept on Location 3286085IPM-ST-WCI-003 Kick Detection Equipment 3286086IPM-ST-WCI-004 Well Control Equipment Testing Requirements 3286087IPM-ST-WCI-005 BOP Stack and Diverter Minimum Requirements 3286088IPM-ST-WCI-006 Well Control Certification 3286089IPM-ST-WCI-007 Consensus of Well Control Procedures 3286090IPM-ST-WCI-008 Well Control Drills 3286091IPM-ST-WCI-009 Casing Liner and Tubing Pressure Testing 3286092IPM-ST-WCI-010 Minimum Chemical Stocks 3286093

6

IDPT Basic WCIPM

IPM Standards (2)Reference Title InTouch #

IPM-ST-WCI-011 Kick Tolerance 3286095IPM-ST-WCI-012 Barriers 3286096IPM-ST-WCI-013 Authority during Well Operations 3286098IPM-ST-WCI-014 Agreement on Specific Well Control Procedures 3286099IPM-ST-WCI-015 Well Shut-in Method 3286101IPM-ST-WCI-016 Well Control Method 3286103IPM-ST-WCI-017 Kick Detection 3286104IPM-ST-WCI-018 Kick Prevention 3286106IPM-ST-WCI-019 Constant Bottomhole Pressure 3286107IPM-ST-WCI-020 Reporting of Kicks 3286108IPM-ST-WCI-021 Shallow Gas Risk Assessment and Contingencies 3286109IPM-ST-WCI-022 Well Control while Running Casing 3286110IPM-ST-WCI-023 Leak Off Test or Shoe Test 3286111IPM-ST-WCI-024 Procedures for Radioactive Sources 3286112IPM-ST-WCI-025 Casing and Tubing Design 3286113IPM-ST-WCI-026 Temporary and Permanent Abandonment 3286114IPM-ST-WCI-027 Wellbore Surveying and Collision Avoidance 3286115IPM-ST-WCI-028 Well Control Briefing Standard 3286116IPM-PR-WCI-002 Contingency Stripping Procedure 3286117IPM-PR-WCI-003 Testing of Cement Mixing and Pumping Equipment 3286118IPM-PR-WCI-004 Operational Requirements for Cement Slurries 3286119IPM-PR-WCI-005 Cement Placement 3286120IPM-PR-WCI-006 Setting and Verification of Cement Plugs 3286122IPM-PR-WCI-007 Survey Program PreparationIPM-PR-WCI-008 Technical and Operational Integrity 3303422

IPM-REF-WCI-001 Derivation of Kick Tolerance Calculation 3286124

IDPT Basic WCIPM

• The primary formula for Well Control

• U-Tube principles

• The calculation of pressures in the Static and Dynamic U-Tube conditions

Basic Well Control

7

IDPT Basic WCIPM

Well Control

• Primary Well Control :• The use of the Mud Weight to provide sufficient pressure to

prevent an influx of formation fluid into the wellbore

• Secondary Well Control:• Control Kick with Mud Weight and BOP Equipment

• Tertiary Well Control:• An Underground Blowout – to avoid a surface blowout

IDPT Basic WCIPM

Well Control Math

Volume:

1 gallon = If MW = 10 ppgP = 10 lb. = 0.52 psi

19.23 in2

Gradient = Change = 0.52 psi/ft

If MW = 1 ppgP = 1 lb. = 0.052 psi

19.23 in2

Gradient = Change = 0.052 psi/ft

Ht: 1

ft.

Area: 19.23 in2

G = 0.052 x MW(psi/ft) (ppg)

230.75 in3

8

IDPT Basic WCIPM

Well Control Math

MW: 10 ppg

Dept

h -f

t

G = 0.052 x MW(psi/ft) (ppg)

HP = G x D(psi) (psi/ft) (ft)

Pres

sure

-psi

0

1

2

3

0

0.52

1.04

1.56Only TVD is Considered

Not MD

IDPT Basic WCIPM

How vs Why

Given:• Gas Kick taken while

drilling at 6000 ft• Well Shut-In• MW = 10 ppg• Kill MW = ???

SIDPP =

SICPP =

600 psi

900 psi

9

IDPT Basic WCIPM

How vs Why

How to calculate KMW:

KMW = (0.052 x 10 x 6000) + 6006000 x 0.052

KMW = 11.923 = 12 ppg

Why KMW is 12 ppg:

G10 = 0.052 x 10 = 0.52 psi/ft

HP10 = G x D = 0.52 psi/ft x 6000ftHP10 = 3120 psiPzone = HP10 + SIDPP = 3120 + 600Pzone = 3720 psi

Gkill = Pzone = 3720 = 0.62 psi/ftD

KMW = Gkill = 0.62 =11.923 ppg=12 ppg6000

0.052 0.052

KMW = (0.052 x MW x D) + SIDPPD x 0.052

IDPT Basic WCIPM

How vs Why

What is the significance of the 600 psiSIDPP?Why was the Drill Pipe gauge pressure used in the calculation rather than the SICP gauge pressure?Why do we round up to 12 ppg for the KMW?

SICPP =900 psi

SIDPP =600 psi

10

IDPT Basic WCIPM

The ‘U’-Tube

An arrangement of pipes in which the two legs are attached at the bottom

The Pressure at Point A = Pressure at Point B

A B

IDPT Basic WCIPM

The Well as a ‘U’-Tube

The ‘U’-Tube Can

Be Either:• Static• Dynamic Pressure Contributors:

• Pump Pressure

• DP Friction Loss

• Bit Pressure Loss

• Annular Pressure Loss (ECD)

• Back Pressure from Choke

What are the Pressure

Contributors?

11

IDPT Basic WCIPM

Static ‘U’-TubeGiven:• Shut-In after Gas Kick• Depth: 10,000 ft• MW: 10 ppg• BHP: ??• Avg Grad Ann: ??• EMW: ??• How Big was the Kick??

SIDPP = 500 psi

SICP = 700 psi

– 8-1/2” Vertical Well– 5 Stands 6-3/4”DC

P1 = P2

IDPT Basic WCIPM

Static ‘U’-Tube

BHP = SIDPP + HPDSBHP = 500 + (0.052 x 10 x 10,000)BHP = 5700 psi

BHP = SICP + HPAHPA = BHP – SICP HPA = 5700 – 700 = 5000 psiGA = HPA = 5000 psi = 0.5 psi/ft

D 10,000 ft

EMWA = GA = 0.5 = 9.6 ppg0.052 0.052

Note that BHP: P1 = P2

SIDPP = 500 psi

SICP = 700 psi

P1 = P2

12

IDPT Basic WCIPM

Static ‘U’-Tube

Height of Influx = SICP - SIDPPGMud - GInflux

= 700 psi - 500 psi(10 ppg x 0.052) - GInflux

Gas Influx: < 0.2 psi/ft Water Influx: > 0.4 psi/ftWorst Case: Assume Gas Influx = 0.1 psi/ft

= 700 - 500 = 200 psi 0.52 psi/ft – 0.1 psi/ft 0.42 psi/ft

Height of Influx = 476.2 ft (TVD)

Kick Size = Height of Influx (MD) x Annular Volume (5 Stands of 6-3/4” DC in 8-1/2” Hole)= 476.2 ft x 0.0259 bbl/ft

Kick Size = 12.4 bbls

IDPT Basic WCIPM

Dynamic ‘U’-Tube

Given:• What does the CDPP

measure?• How are DP losses

calculated?• How are Annular pressure

losses calculated?

P1 ≥ P2

CDPP psi

CCP psi

13

IDPT Basic WCIPM

DS Pressure Loss

• Step 1: Obtain the following dimensional parameters• Drill pipe ID ddp – inches• Drill pipe Length Ldp – feet• Drill collar ID ddc – inches• Drill collar Length Ldc – feet• Plastic Viscosity PV – centipoise• Yield Point YP - lb/100ft2

• Step 2: Calculate the average fluid velocity (ft/sec):• Drill collars: Vdc = GPM/(2.448 x ddc

2)• Drill pipe: Vdp = GPM/(2.448 x ddp

2)

IDPT Basic WCIPM

DS Pressure Loss

• Step 3: Calculate the frictional pressure loss:• Drill collars:

PLdc = [(PV x Vdc x Ldc)/(1500 xddc2)] + [(YP x Ldc)/(225 x ddc)]

• Drill pipe:PLdp = [(PV x Vdp x Ldp)/(1500 xddp

2)] + [(YP x Ldp)/(225 x ddp)]

• DSPL = PLdc + PLdp

14

IDPT Basic WCIPM


Given:• Depth: 10,000 ft• MW: 10 ppg• Circ DPP (CDPP): 2000 psi• Circ CP (CCP): 500 psi

• (backpressure)

• DS Pres Loss (dPDS): 1300 psi• Anl Pres Loss (dPA): 200 psi• BHP: ???

P1 ≥ P2

CDPP = 2000 psi

CCP = 500 psi

IDPT Basic WCIPM


BHP = CCP + HPA + dPA

= 500 + (0.052 x 10 x 10,000) + 200BHP = 5900 psi

BHP = CDPP + HPDS - dPDS

BHP = 5900= 2000 + (0.052 x 10 x 10,000) - 1300

OR

P1 ≥ P2

CDPP = 2000 psi

CCP = 500 psi

15

IDPT Basic WCIPM

Problem #1

THE ‘U’ –TUBE1/2 hour

IDPT Basic WCIPM

10 9.7

+350

156

0

SICP = 0 psi (overbalanced U-Tube)

BHP = SICP + HPAnn= 0 + (0.052 x 10 ppg x 10,000 ft)

BHP = 5200 psi

SITP = BHP - HPTub= 5200 – (0.052 x 9.7 ppg x 10,000 ft)

SITP = 156 psi

Zone Overbalance = BHP – Zone Pressure= 5200 – 4850 psi

Zone Overbalance = 350 psi

Problem #1

16

IDPT Basic WCIPM

+650

156

370

CTP = 156 psi (Held Constant)

CCP = dPAnn+ dPTub= 300 + 70

CCP = 370 psi

BHP = CCP + HPAnn - dPAnn= 370 + 5200 – 70

BHP = 5500 psi


Zone Overbalance = 650 psi ( 300 psi above Shut-In)

Problem #1

IDPT Basic WCIPM

+623

0

370 L

CTP = 0 psi (U-Tube Balanced)(Choke Fully Open)

CCP = dPAnn + dPTub= 300 + 70

CCP = 370 psi (Pressure Loss in U-Tube)

Volume of 9.7 ppgAnn = Volume of 10 ppg TubL x CapacityAnn = (10,000 – L) x CapacityTubL x 0.0986 = (10,000 – L) x 0.02

= 200 – L x 0.020.1186L = 200L = 1686 ft10,000 – L = 8314 ft

BHP = CTP + HP9.7 + HP10 - dPT= 0 + (0.052 x 9.7 ppg x 1686 ft) + (0.052 x 10 ppg x 8314 ft) + 300= 0 + 850 + 4323 + 300

BHP = 5473 psi



Problem #1

17

IDPT Basic WCIPM

+650

0

402 L

CTP = 0 psi (HPTub Greater than HPAnn)(Choke Fully Open)

BHP = CTP + HPT + dPT = 0 + 5200 + 300

BHP = 5500 psi



Volume of 9.7 ppgAnn = Volume of 10 ppg TubL x CapacityAnn = 10,000 x CapacityTubL x 0.0986 = 10,000 x 0.02L = 2028 ft10,000 – L = 7972 ft

BHP = CCP + HP9.7 + HP10 - dPAnnCCP = BHP - HP9.7 - HP10 + dPAnn

= 5500 - (0.052 x 9.7 ppg x 2028 ft) + (0.052 x 10 ppg x 7972 ft) + 70= 5500 - 1023 - 4145 + 70

CCP = 402 psi

Problem #1

IDPT Basic WCIPM

0

526

+650

CTP = 0 psi (HPTub Greater than HPAnn)(Choke Fully Open)

BHP = 5500 psi (Same as (#4))

Zone Overbalance = 650 psi (Same as (#4))

CCP = BHP – HPAnn + dPAnn= 5500 - (0.052 x 9.7 ppg x 10,000 ft) + 70= 5500 - 5044 + 70

CCP = 526 psi

Problem #1

18

IDPT Basic WCIPM

+494

0

370

CTP = 0 psi (U-Tube Balanced)(Choke Fully Open)

CCP = 370 psi (Pressure Loss in U-Tube)

BHP = CTP + HPTub + dPTub= 0 + 5044 + 300

BHP = 5344 psi



Problem #1

IDPT Basic WCIPM

0

100

200

300

400

500

600

0 1 2 3 4 5 6

370402

526

370

156

CTP/

CCP

-psi

Tubing Volumes

Problem #1

19

IDPT Basic WCIPM

0

100

200

300

400

500

600

700

800

900

1000

0 1 2 3 4 5 6

Tubing Volumes

650 650

623494

Over

bala

nce

-psi

Problem #1

IDPT Basic WCIPM

Kicks – Cause

There is ONE condition that allows a kick to occur:

The pressure in the wellbore becomes less than the pressure in the formation

20

IDPT Basic WCIPM

Kicks – Causes and Prevention

Cause Best Prevented By: Most Common

Least Common

1. Failure to keep hole full of proper weight fluid

Measurement of fill-up volume when tripping -

2. Drilling into zones of knownpressure with mud weight too low

Good engineering & well procedures and an alert, questioning attitude by WSS -

3. Drilling into unexpected, abnormal formation pressure

Careful engineering, proper well design -

Trip Tank!!

STUDY OFFSET WELLS

READ THE PROGRAM

IDPT Basic WCIPM

Kicks – Causes and Prevention

Most Common

Least Common

Careful engineering, proper well design -Case off Loss Circ ASAP!

5. Unloading mud by pulling balled assembly

Measurement of fill-up volume when pulling drill string – TRIP TANK!

6. Mud weight high enough to drill, but not to trip

4. Lost Circulation (Fluid Level, not rate of loss is critical in well control)

Measurement of fill-up volume when pulling drill string – TRIP TANK!

Cause Best Prevented By:

21

IDPT Basic WCIPM

Uncontrolled Kicks = Blowouts

Don’t Let it Happen

IDPT Basic WCIPM

Well Control Equipment

• Trip Tank

• LP and HP Well Control Equipment

• BOP Configuration and testing

• Accumulator, Manifold and Mud Gas Separator

22

IDPT Basic WCIPM

Well Control Equipment - Overview

HIGH PressureLOW Pressure

Pump

Trip Tank

Choke

Accum

Gas Buster DegasserSuction

MudStorage

Mud Mixing PVT

BOP StackWell Head

DP

To Pump

CSG

IDPT Basic WCIPM


What is the most important piece of well control equipment on the rig?

The Trip Tank

23

IDPT Basic WCIPM

Surface BOP Stack Configuration

Choke Line HCR

TOP RAMS

BLIND RAMS

BOTTOM RAMS

ANNULAR

BOTTOM RAMS

Kill Line

VR Plug Installed in

Casing Head

Replace with Double Gate (Pipe Rams – Blind Rams) in Selected Cases

IDPT Basic WCIPM

Sub-Sea BOP Stack Arrangement

BLIND RAMS

BOTTOM RAMS

UPPER ANNULAR

LOWER RAMS

BOTTOM RAMS

MIDDLE RAMS

BOTTOM RAMS

UPPER RAMS

BOTTOM RAMS

SHEAR RAMS

LOWER ANNULAR

LMRP CON

Stack Connector

Outer Choke

Inner Choke

Inner Choke

Outer Choke

Inner Choke

Outer Choke

Inner Choke

Outer Choke

24

IDPT Basic WCIPM

Pressure Test Frequency

During the first trip after the14-day interval with a maximum interval of 21 days or before as specified by local regulationsPrior to installation where possibleAfter installation of wellhead and BOP assembly and prior to drillingWhen any component change is madePrior to drilling into a suspected high pressure zoneAt any time requested by the Operator’s Drilling RepresentativeAfter RepairsPrior to the initial opening of the drill stem test toolsWhen bonnets have been opened solely for the purpose of changing rams prior to running casing, a body test to ensure the integrity of the bonnet seals will suffice

The pressure tests of all blowout preventers, wellhead components and their connections, BOP operating unit, choke manifold, kill and choke lines, standpipe manifold, kelly and kelly cocks, safety valves and inside BOPS shall be made:

IDPT Basic WCIPM

Accumulator Bottle

Bladder Assembly

Shell

Fluid Port Assembly

25

IDPT Basic WCIPM

Accumulator Sizing

PRECHARGEVOLUME AT

ACCUMULATOR OPERATING PRESS

MIN OPER PRESS 200 psi ABOVE

PRECHARGE PRESS

USABLE VOLUME

- MOST ALL MODERN ACCULULATORS ARE 3000 psi WORKING PRESSURE

Non

-Fla

mm

able

Gas

1200 psi

1000 psi

Acc

umul

ator

Fl

uid

3000 psi

IDPT Basic WCIPM

Accumulator SizingSLB STANDARD

SPECIFICATION:

• Close all (rams and annular) functions and Open all HCRs valves• Open all (rams and annular) functions and Close all HCRs valves• Close Annular• Open choke line remote operated valve

The accumulator volume of the BOP systems should be sized to keep a remaining stored accumulator pressure of 1380 kPa (200 psi) or more above the minimum recommended precharge pressure after conducting the following operations (with pumps inoperative):

26

IDPT Basic WCIPM

EXAMPLE:

BOP Equipment: 1 Annular + 3 Rams + HCR Valve

Usable Volume (UV): = 133 Gal

Closing Volume (CV): 20 + (3 x 10) + 1 = 56 Gal

Nominal (Bottle) Volume (NV): 2 x UV = 266 Gal

Opening Volume (OV): 20 + (3 x 10) + 1 = 56 GalClosing Volume (CV): 20 = 20 GalOpen Choke Line Valve (OV): 1 = 1 Gal

Accumulator SizingSLB STANDARD

IDPT Basic WCIPM

Accumulator Sizing

Calculation of Usable (Bottle) Volume

1.676.670Liquid Vol

10,00010,00010,000P x V

8.333.3310Gas Vol

120030001000Pressure

UseableOperatingPre-Charge

UV = 6.67 – 1.67

UV = 5

1 2 3Non

-Fla

mm

able

Gas

3000 psi

1200 psi

1000 psi

Acc

umul

ator

Fl

uid

USABLE VOLUME

27

IDPT Basic WCIPM

Hydraulic Pumps

SPECIFICATION:

• Closing annular preventer (excluding diverter) on minimum size drill pipe being used

• Opening hydraulic operated choke line valve• Obtain a minimum of 1380 kPa (200 psi) pressure above accumulator precharge

pressure on closing unit within two (2) minutes or less

The unit will include one (1) electric pump and two (2) back-up air pumps for accumulator charging. With the accumulator system removed from service, the pumps should be capable of:

IDPT Basic WCIPM

Choke and Standpipe Manifold

At least three flow paths must be provided that are capable of flowing well returns through conduits that are 76.14 mm (3”) nominal diameter or larger. At least one flow path:

• Shall be equipped with a remotely controlled, pressure operated adjustable choke. Simplified choke manifolds without remote control choke may be acceptable on light rigs with 2-3k psi stacks.

• Shall be equipped with a manually operated adjustable choke.• Must permit returns to flow directly to the pit, discharge manifold or other

downstream piping without passing through a choke. Two gate valves with full rated working pressure must be provided in this unchoked path.

28

IDPT Basic WCIPM

Float Valves

SPECIFICATION:

• Prevent sudden influx entry into the drill string• Prevent back flow of annular cuttings from plugging bit nozzles

Either plain or ported floats are acceptable

Float valves must be used while drilling and opening hole prior to setting surface casing or any time the posted well control plan is to divert and can also be used in deeper sections of the hole. They:

IDPT Basic WCIPM

Mud-Gas Separator

From Choke

Impi

ngem

ent

Plat

e

Baffle Plates

1. Diameter and length controls the amount of pressure in separator

2. Height and diameter and internal design control separation efficiency

Drain Line w/Valve

Vent Line

No Valves!!

MUD

GA

S

3. Height of ‘U’-Tube (D) and distance from bottom of separator to top of ‘U’-Tube controls fluid level and stops gas from going out of the bottom

Siph

on B

reak

erD

dNo

Valv

es!!

Mud

29

IDPT Basic WCIPM

Exercise - MGS Design

IDPT Basic WCIPM

EXAMPLE:Well Depth: 10, 000’

Hole/CSG Size (12-1/4” x 13-3/8”): 0.125 bbl/ftDrill Pipe (5”, 19.5#): 0.025 bbl/ft

MW: 12 ppg KMW: 14 ppg

Kick Vol: 50 bbl

Kill Speed: 3 BPM

Well Killed by Driller’s Method Csg Press when gas reaches surface: 1987 psiCsg Press when gas out: 1057 psi

Avg Gas Rate during 1st minute of venting: 3,202 MCF/DAvg Gas Rate during last minute of venting: 1,722 MCF/DAvg Gas Rate while venting: 2,462 MCF/D


30

IDPT Basic WCIPM

0 5 10 15 20

Pressure Loss in 100 ft

0 5 10 15 20

5

1

0

1

5

2

0

2

5

30

Gas Flowrate – MMSCF/D

Upst

ream

Pre

ssur

e –

psi

4” ID 6” ID

8” ID10” ID

12” ID

Gas Temp = 75º F

Downstream Pressure = Atmospheric


IDPT Basic WCIPM

DIVERTERS


Are NOT Well Control Equipment

31

IDPT Basic WCIPM

Diverters

• Diverter Requirements

• Diverter Procedures

IDPT Basic WCIPM

Designed to direct UNCONTROLLED flow away from personnel

• Major weaknesses of the Diverter:1) Plugging:

A large number particles of this size: Can bridge off these flow paths:

2) Erosion:• Gas/Sand mixtures flowing through diverter lines have been measured

to erode though steel at the rate of 8”/hour

• Water mixtures have been measured at 16”/hour

NO RELIABLE MEANS EXIST TO ELIMINATE THESE PROBLEMS

Diverters

8” 12”

1/4 -1/2”

32

IDPT Basic WCIPM

Diverter Configuration

Surface

Casing Shoe

Riser

Diverter

Entry

Diverter Line

Flow Line

IDPT Basic WCIPM

SLB Diverter Requirements Land, Swamp Barge & Jack-Up

Relief Lines• At least two relief lines installed to permit venting at

opposite ends or sides of the rig• On Land a single line is permissible

• The relief line shall be at least 8” (203 mm)• No other lines into or out of diverter lines or housing

33

IDPT Basic WCIPM


Relief System• The diverter relief system shall be inserted with a minimum number of

bends and all lines well secured. Each diverter relief line will be equipped with a pressure-operated full opening, unrestricted valve. The operating sequence of the diverter will be as follows:• Open selected valve• Close diverter

These functions shall be interlocked. A means of switching flow from one vent to the other without closing in the system must beprovided.

IDPT Basic WCIPM


Relief System• Special care should be taken to protect pipe bends form erosion. This may

include:• Use of long radius pipe bends• Providing extra metal thickness at bends• Sleeve-type connections shall not be used in the diverter system• A power-operated valve must be installed to automatically shut off mud returns

to the pits when the diverter is closed, if the mud return line and diverter relief outlet from the well is a common outlet or the mud return line connects below the diverter head

34

IDPT Basic WCIPM


Relief System• Special care should be taken to protect pipe bends form erosion. This may

include:• Use of long radius pipe bends• Providing extra metal thickness at bends• Sleeve-type connections shall not be used in the diverter system• A power-operated valve must be installed to automatically shut off mud returns

to the pits when the diverter is closed, if the mud return line and diverter relief outlet from the well is a common outlet or the mud return line connects below the diverter head

IDPT Basic WCIPM

Shut-In Procedure while Drilling

Paths on Choke Manifold Closed (Hard Shut-In), Float in Drill string

2. Raise string to shut-in position (time permitting)3. Stop the pumps and flow check; if well flows,

proceed without delay to next step4. Close annular/ open remote controlled choke line valve (HCR)5. Notify man in charge6. Check space out and close pipe rams and locks7. Bleed off pressure between pipe rams and annular (if possible)8. Record annulus and drill pipe pressure and pit gain

1. Stop rotation

35

IDPT Basic WCIPM

4. Notify man in charge

Shut-In Procedure while Tripping

1. Set slips below tool joint (No tool next to shear ram)2. Install full opening safety valve and close same3. Close annular/open remote controlled choke line valve (HCR)

between safety valve and top drive) and open safety valve6. Read annulus and drill pipe pressure and pit gain

5. Make up kelly or top drive (insert a pup joint or single

Paths on Choke Manifold Closed (Hard Shut-In), Float in Drill string

IDPT Basic WCIPM

Hard Shut-In vs. Soft Shut-In

Hard Shut-InAdvantages:

• Influx stopped in shortest possible time• Quick and simple procedureDisadvantages:• Perceived pressure pulse or ‘Water Hammer’ effect that is

thought to damage formation

36

IDPT Basic WCIPM

Hard Shut-In vs. Soft Shut-In

Soft Shut-InAdvantages:

• Perceived pressure pulse is reducedDisadvantages:• A larger influx is obtained due to the delay in fully shutting

the well in• More complex due to requirement of ensuring valve

alignment before closing BOP

IDPT Basic WCIPM

Hard Shut-In vs. Soft Shut-In Conclusions

Soft Shut-In• Little improvement to pressure pulse• Significant effect from additional influx

Hard Shut-In• ‘Water Hammer’ smaller than shut-in pressure rise• Formation exposed to lower net pressure• Results favor Hard Shut-In

• Minimum confusion, Less influx volume, Lower annular pressure

• Safety of personnel and equipment without risk to well

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IDPT Basic WCIPM

Well Kill ProceduresCONSTANT BHP WELL CONTROL METHOD

Circulate Gas Out Holding Constant BHP

P1 = P2

IDPT Basic WCIPM

Well Kill Procedures

• 4 Methods• Drillers Method

• Circulate kick out• Then pump kill weight mud

• Wait and Weight Method• Mix KW mud (Well shut in) and pump into wellbore.

• Volumetric, Lubricate and Bleed• When circulation is a problem

• Bullheading

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IDPT Basic WCIPM

ADVANTAGES

Driller’s Method

• Simplicity – Less calculations are required than Wait and Weight• Can start circulation immediately – Effect of gas migration reduced• Removes influx and stabilizes wellbore pressure at earliest possible time• Viable option if limited barite is available

DISADVANTAGES• Method will require at least two circulations • Under certain conditions the highest shoe pressure• Two circulations may cause damage to Well Control Equipment

IDPT Basic WCIPM

Wait and Weight Method

• In some circumstances, it generates the lowest pressure on the formation near casing seat.

• In a long open hole section, it is the least likely method to induce lost circulation.

• Requires one less circulation, therefore less damage to Well Control Equipment

• Defacto standard for majority of our clients

• Requires longest waiting period prior to circulation. In a case where a significant

amount of hole is drilled prior to encountering the kick, the cuttings may settle out

and plug annulus

• Gas migration is a problem while the density of the system is increased

ADVANTAGES

DISADVANTAGES

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IDPT Basic WCIPM

Well Control Incident Reporting

• All WC Incidents will be reported in QUEST within 24 hours of the incident.

• The QUEST entry shall be accompanied by a Well Control Incident Report

IDPT Basic WCIPM


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IDPT Basic WCIPM


IDPT Basic WCIPM


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IDPT Basic WCIPM

• Now you should be able to:

• Define the terms “kick” and “Blowout”

• Understand the causes of kicks and blowouts

• Describe primary, secondary and tertiary WC procedures

• Perform basic WC calculations

• Describe the necessary equipment for Well Control

• Be able to report a WC incident in Quest

• Fill out a killsheet.

Basic Well Control

50495081 Basic Well Control

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Transcript of 50495081 Basic Well Control