stimulation technology stimgun™€¦ · stim technology the basic process tamping liquid fluid...

© 2009 Baker Hughes Incorporated. All Rights Reserved.

Stimulation Technology StimGun™

Nov 29, 2011

Bassam Salim

© 2009 Baker Hughes Incorporated. All Rights Reserved.

Perforating Factors Affecting Flow Efficiency

•Shot Density, Gun Phasing •Depth of Penetration•Hole Diameter •Casing, Cement Sheet & Rock Density•Skin Effect (Crushed Zone)•Method of Perforating

Depth of Penetration

7

Skin and CFE

VirginVirginReservoirReservoir

KK

Damaged Damaged ZoneZoneKdKd

Cem

ent a

nd C

asin

gC

emen

t and

Cas

ing

Towards wellbore

ReservoirReservoirpressurepressure00

11

SS

KK

II

NN

IPRIPR

What We Often Get

© 2009 Baker Hughes Incorporated. All Rights Reserved.

Method of Perforating

Under Balance

Over Balance

Petrophysical Evaluation

Avg. Phi:25 puAvg. Sw:50 %

Avg. Phi:30 puAvg. Sw:58 %

Run 3

Run 2

Run 1

Stim gun

Well X Formation Y Depth to Top (f t ) xxxx Perfed Interval (f t) 60 Permeability (md) 1 Skin + ? Porosity 25-30 Pressure (psi) 3000

Run 6

Run 4

Run 5

© 2009 Baker Hughes Incorporated. All Rights Reserved.

Pre job Planning

Kept the hole open, no casing and cement

Drilled 6” hole to minimize the formation damage

Used best penetrating charges for the Gun size

Perforated the interval twice to improve SD, PH

Perforating Under balance to minimize Skin Effect

Plan the operation to achieve 1000 psi under balance

Stimulate the perforation using Acid

WELL X Acid Injection After Open Hole Perforation

Stim Technology The Basic Process

TampingLiquid Fluid Motion in

Well

Energy Source (Propellant, Perf Gun, Explosive, etc.)

Expanding Gasified ‘Bubble’

WellboreInterior

Possible Surface Overpressure

Flow into Fracture (One of 1-12 Shown)

The Effect of Energy Release Rate

Fracturing

Fracturing

P

T

Explosive

RockCrushing

Microseconds

~>105 psi

P

T

Propellant

Milliseconds

~>104 psi

Fracturing

Seconds

P

T

Hydrofracture or Overpressured Gas~>103 psi

Breaking Down the Perforation

© 2009 Baker Hughes Incorporated. All Rights Reserved.

StimGun Surface Test

StimGun Surface Results

© 2009 Baker Hughes Incorporated. All Rights Reserved.

Propellant Lab Stimulation (90 Phased Perforated Core)

StimGun in the Field

StimTube Tool Before and After

Before

After

WST Carriers• The reusable carriers have holes sizes from 0.75-2.75” and several hole

densities. One inch holes at 12 per foot is the standard.

PulsFrac™ Computer Software

Simulates the Event: Hi

–Pressure vs. Time–Perf Breakdown–Frac Extension–Fluid Motion–Casing Differential

PulsFrac Pressure Wave Calculationthat Matches Data

•Pressure vs. Depth •Time (0 – 80 ms)

Well XLBM Formation Stimulation

Run 3

Run 1

Run 3

Run 1

Run 2 Run 2

WELL XAcid Injection After the Propellant Stimulation

© 2009 Baker Hughes Incorporated. All Rights Reserved.

Conclusion

•Knowing the low Permeability Rocks need deep perforating tunnels, and

•The High Permeability Rocks need deep perforating tunnels simultaneously withlarge hole entry diameter

• The depth of penetration is indirectly proportional with hole diameter, as well the CFE.

The solution isThe StimGun