Long Term Integrity of Cement Systems Oct 4, 2002

Agenda Participants/Financials Project Focus/Management Project Tasks Summary Action Items

Participants Commitments MMS, Petrobas, Unocal, BP, ExxonMobil Saudi Aramco, ONGC, Conoco, AGIP DOE, Anadarko, PDVSA Potentials ChevronTexaco, Stat Oil What about Service Companies ?

Financials Commitments - $50k each $600k 12 Companies Potential additional $100 to 150k Project Timing – 18 months

Management of Project Fred Sabins – Project Manager Bryan Simmons – Operations Manager Lab support CSI Westport Rock Mechanics Mathematical Analysis – University of Houston Rock Properties Instruments - Chandler

Project Communications Steering Committee – Voting Members Meeting notes/ voting privileges Short Monthly reports - Technical Quarterly Progress Report/Meeting Feb 2003

Project Objective Determine the cement system properties that effects the ability of cements to seal fluids Primarily in Deep Water General application Develop a correlation of the cement properties to performance Determine laboratory methods to determine key properties

Tasks Task 1 – Problem Analysis Task 2 – Property Determination Task 3 – Mathematical Analysis Task 4 – Testing Baseline Task 5 – Refine Procedures Task 6 – Composition Matrix Task 7 – Conduct Tests Task 8 – Analyze Results Task 9 – Decision Matrix

Testing Program Deep Water/All Conditions in Gulf of Mexico Cement Slurries Class A Foamed Cement Bead Cement Class H Latex Cement Other modifications of above

Conventional Tests Conditions – 45 F BHST, 65 F BHCT Tests Thickening Time - 4 to 6 hours Free Water < 1% Compressive Strength (24hr and 14 days) Fluid Loss, SGS when appropriate

Thickening Time & Free Water Slurry CompThickening Time % Free Water Type 14: ppg Foam 3: ppg Bead 5:040.8 Latex6:150.5

Mechanical Integrity Issues Flow of Fluids Around the Cement Bonding, Microannulus, Deformation Through the matrix of the Cement Cracking, Permeability changes Stress Pressure, Temperature, Pipe Buckling, Formation Compaction Cycling Conditions

Mechanical Properties Rock mechanics/Acoustic Measurements Tensile Strength/Youngs Modulus (T) Young’s Modulus/Poisson’s Ratio

Tensile Strength Brazilian Test Method Tensile Strength Young’s Modules Maximum Yield

Tensile Strength and Young’s Modulus Slurry Tensile Strength(psi) Young’s Modulus Foam(12ppg) E 4 Type I394/ /8.16 E 4 Type I with Fibers Latex E 4 Latex with Fibers E 4

Young’s Modules Compressional Tests Confining Loads – Defined by 0psi break Base line 14 day cure Acoustic Data Poisson’s Ratio

Comparison of Compressive Strength LocationCompressive Strength 45 F Compressive Strength 80 F Westport CSI

Type 1 CYM Confining Pressure Effective Strength psi Young’s Modules psi E E E 5

12 ppg Foam CYM Confining Pressure Effective Strength psi Young’s Modules psi E E E 5

12 ppg Bead CYM Confining Stress Effective Strength psi Young’s Modules E E E 6

Latex CYM Confining Stess Effective Strength psi CYM psi E E E 5

Hydrostatic Cycles 10 ppg foam

Acoustic Measurements Chandler’s New Mechanical Properties Device

Chandler Device SlurryPRComp. YM Type E 6 Beads E 6 Latex E 6 Latex/Fibers E 6 Class H E 6 Class H Fibers E 6

Rock Mechanic Data SlurryPRComp. YM Type 11.7 E 6 Type 1 Beads9.5 E 5 Type 1 Latex5.6 E 5 Type 1 Latex/Fibers Class H Class H Fibers

Performance Tests Shear Bond Measurements (Cycling conditions) Soft formations Hard Formations Annular Seal/Hassler Sleeve (Cycling Conditions) Soft Formations Hard Formations

Temperature Cycling Procedures Samples are then cured at 45°F for 14 days. Samples are then temperature cycled from 45°F to 180°F to 45°F as described below: Samples are placed in a 96°F water bath for 1 hour. Samples are placed in a 180°F water bath for 4 hours. Samples are placed in a 96°F water bath for 1 hour. Samples are placed back in a 45°F water bath. The samples are cycled once per day during the cycling period.

Shear Bonds SystemType 1FoamBeadsLatex Base P /98109/ Base S Temp P165299/215191/ Temp S Press P194/106276/228294/ Press S2322 C23 C11

Annular Seal Test Configurations Plastisol Sleeve Pipe-in-soft configurationPipe-in-pipe configuration

Annular Seal Tests Annular SealClass AFoamedBead Initial Flow- Pipe in Pipe 0 Flow Initial Flow- Pipe in Soft 0 Flow0.5K(md)0 Flow Temperature Cycled- Pipe in Pipe 0 Flow Temperature Cycled- Pipe in Soft 0 Flow123K md/(2200 md) 43K(md)(cracked during cycling) Pressure Cycled- Pipe in Pipe 0 Flow Pressure Cycled- Pipe in Soft 27K(md) 0.19K (md)(cracked during cycling) 3K(md)

Annular Seal Test Model N 2 In N 2 Out Confining Pressure Seal for Confining Pressure Rubber Sleeve

Pipe in Pipe Testing No fluid external to the cement 6” flanged models 6” flanged model with pressure (200 psi) 5’ flanged model vacuum system 5’ flanged model with pressure (200 psi) Conclusion – tight seal to gas

Mathematical Model Presented by: University of Houston

Future Work

YM Hydrostatic 10 ppg foam

YM (Hyd + Cycle) 10 ppg foam

YM Cycle 10 ppg foam