SLAPS-16-24 A review of the methods and modeling for ...perforators.org/wp-content/uploads/2016/10/SLAPS-16-24_A-review-of...introduction open perforation cement ... dynamic underbalanced

2016 LATIN AMERICA PERFORATING SYMPOSIUM, BUENOS AIRES

A REVIEW OF THE METHODS AND MODELING FOR

DYNAMIC UNDERBALANCE PERFORATING

AUTHORS: David Cuthill, GEODynamics, Inc.; Martin Tilbrook, Vause

(Thailand); Wararit Toempromraj, PTTEP; Terrell Saltarelli, GEODynamics, Inc.

SLAP 16-24

1 A REVIEW OF THE METHODS AND MODELING FOR DYNAMIC UNDERBALANCE PERFORATING

SLAP 16-24

� A dynamic underbalance, at the time of perforating, can be obtained by using separate atmospheric chambers or by increasing the flow area in the main perforating gun

� When the perforating gun fires, the chambers and perforating gun body open to the wellbore and a short duration underbalance is created

INTRODUCTION

Open Perforation

Cement

Casing

Charge and

Core Debris

Pulverization Zone

Grain Fracturing Zone

Compacted Zone

(Damaged Perm., kc)

Undamaged

Permeability, k

Drilling Damaged

Permeability, kd

2 A REVIEW OF THE METHODS AND MODELING FOR DYNAMIC UNDERBALANCE PERFORATING

SLAP 16-24

� This underbalance event can improve clean up of the compacted region around the perforation tunnel

• Assuming both the amplitude of the underbalance is sufficient and the time to maximum underbalance pressure is rapid enough

INTRODUCTION

Open Perforation

Cement

Casing

Charge and

Core Debris

Pulverization Zone

Grain Fracturing Zone

Compacted Zone

(Damaged Perm., kc)

Undamaged

Permeability, k

Drilling Damaged

Permeability, kd

A REVIEW OF THE METHODS AND MODELING FOR DYNAMIC UNDERBALANCE PERFORATING

SLAP 16-24

3

INTRODUCTION

� Various configurations can be used to create the dynamic underbalance, including

• Large exit hole diameter punch charges in the main perforating carrier or on the adjoining chambers; or

• A dynamic surge vent can be placed between the loaded perforating carrier and the atmospheric chamber

• In both cases the punch charges or vent system rapidly opens at the time of gun detonation

� Each system has its merits; with proper system configuration and the use of wellbore dynamics modeling, a dynamic underbalance can be achieved both economically and repeat-ably

4 A REVIEW OF THE METHODS AND MODELING FOR DYNAMIC UNDERBALANCE PERFORATING

SLAP 16-24

� The underbalance is created from the perforating carrier or through the use of additional chambers above or below the perforating carrier

� The chambers serve to increase the volume available to create the underbalance

DYNAMIC UNDERBALANCED PERFORATING

Underbalanced

Chamber

Perforating

Gun

Punch

Charges

Underbalanced

Chamber

Punch

Charges

5 A REVIEW OF THE METHODS AND MODELING FOR DYNAMIC UNDERBALANCE PERFORATING

SLAP 16-24

� When the gun fires, the chambers and perforating gun body open to the wellbore and a short duration underbalance is created

� Punch charges can be interspersed with the main perforating carrier or can be placed within the adjoining chambers in order to increase the flow area and open the chambers to the wellbore

DYNAMIC UNDERBALANCED PERFORATING

A REVIEW OF THE METHODS AND MODELING FOR DYNAMIC UNDERBALANCE PERFORATING

SLAP 16-24

6

DYNAMIC UNDERBALANCED PERFORATING

Main gun detonation

Maximum underbalance

Time to max underbalance

7 A REVIEW OF THE METHODS AND MODELING FOR DYNAMIC UNDERBALANCE PERFORATING

SLAP 16-24

� A dynamic surge vent was developed as an alternative to or in addition to punch charges

� Initially for horizontal applications with long space-outs

� This vent is placed between the loaded perforating carrier and the atmospheric chamber

� The vent rapidly opens at the time of gun detonation and exposes the chamber to wellbore pressure and creates a dynamic underbalance

DYNAMIC SURGE VENT

8 A REVIEW OF THE METHODS AND MODELING FOR DYNAMIC UNDERBALANCE PERFORATING

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� Main carrier detonation causes an internal sleeve to move and allow flow through the vent into the chamber

� Downhole pressure recordings indicate that the vent begins opening at about 0.002 ms after carrier detonation

DYNAMIC SURGE VENT

Vent hole

9 A REVIEW OF THE METHODS AND MODELING FOR DYNAMIC UNDERBALANCE PERFORATING

SLAP 16-24

Applications/Advantages

� The vent system allows for the chamber carrier to be reused

� The detonation train can continue below the vent to allow detonation of lower carriers and triggering of other vents

� Provides a completely open volume

� No charge loading tube or resulting debris which would be present when a punch charge is used allowing for greater chamber volume available

� Field serviceable

DYNAMIC SURGE VENT

10 A REVIEW OF THE METHODS AND MODELING FOR DYNAMIC UNDERBALANCE PERFORATING

SLAP 16-24

� Can be loaded in the main carrier substituting conventional charges or within the chamber carrier

� Designed to provide large diameter exit hole in the carrier without risk of perforating casing

� Shot density and placement within the main carrier or chamber is completely flexible

� Placed in the same loading tube as conventional charges

PUNCH CHARGES

� Exit hole diameter 1.05 inches

� Shot load 8 grams

� Explosive RDX, HMX, or HNS

� Carrier Sizes 2-3/4 – 7 inch

11 A REVIEW OF THE METHODS AND MODELING FOR DYNAMIC UNDERBALANCE PERFORATING

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• Interval depth – 1850 mTVSS

• Sandstone

• 11% porosity

Perforating configuration

• 6 m perforated interval

• 4-1/2 inch carrier/ 39 gram charge

• 3 m chamber below

EXAMPLE 1

Well Configuration

12 A REVIEW OF THE METHODS AND MODELING FOR DYNAMIC UNDERBALANCE PERFORATING

SLAP 16-24

0

1000

2000

3000

4000

5000

6000

7000

8000

9000

10000

-0.05 0 0.05 0.1 0.15 0.2 0.25

Pre

ssu

re (

psi

)

Time (s)

EXAMPLE 1

� Other runs where made with good repeatability

A REVIEW OF THE METHODS AND MODELING FOR DYNAMIC UNDERBALANCE PERFORATING

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13

MODELING RESULTS

14 A REVIEW OF THE METHODS AND MODELING FOR DYNAMIC UNDERBALANCE PERFORATING

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• Interval depth – 1665 mTVSS

• Sandstone

• 23% porosity

Perforating configuration

• 4.5 m perforated interval

• 4-1/2 inch carrier/ 39 gram charge

• 3 m chamber below

EXAMPLE 2

Well Configuration

0

1000

2000

3000

4000

5000

6000

-0.1 0 0.1 0.2 0.3 0.4 0.5

Pre

ssu

re (

psi

)

Time (s)

A REVIEW OF THE METHODS AND MODELING FOR DYNAMIC UNDERBALANCE PERFORATING

SLAP 16-24

15

SUMMARY

Dynamic Surge Vent

� Vent can be used in place of or in combination with punch charges

� For longer intervals where more chamber volume may be required – costs associated with carriers and punch charges can be eliminated and the chamber carriers can be reused

� More chamber volume is available since the punch charges and associated loading tube is eliminated

Punch charges

� Punch charges allow for greater flexibility in system configuration and can provide greater flow area compared to the dynamic vent since the shot density is completely adjustable

2016 LATIN AMERICA PERFORATING SYMPOSIUM, BUENOS AIRES

QUESTIONS? THANK YOU! QUESTIONS? THANK YOU! QUESTIONS? THANK YOU! QUESTIONS? THANK YOU!

SLAP 16-24

A REVIEW OF THE METHODS AND MODELING FOR DYNAMIC UNDERBALANCE PERFORATING