# Presentation: 826441

## 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 - Email
- 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 Comp | Thickening Time | % Free Water |
| --- | --- | --- |
| Type 1 | 4:38 | 0.8 |
| 12.0 ppg Foam  | 3:42 | 0 |
| 12.0 ppg Bead | 5:04 | 0.8 |
| Latex | 6:15 | 0.5 |

## 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) | 253 | 3.23 E 4 |
| Type I | 394/213 | 19.15/8.16 E 4 |
| Type I with Fibers |  |  |
| Latex | 539 | 5.32 E 4 |
| Latex with Fibers | 902 | 8.5 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

| Location | Compressive Strength
45 F | Compressive
Strength
80 F |
| --- | --- | --- |
| Westport | 1400 | 2015 |
| CSI | 1455 | 1920 |

## Type 1 CYM

| Confining Pressure | Effective Strength psi | Young’s Modules psi |
| --- | --- | --- |
| 0 | 8645 | 16.7 E 5 |
| 1500 | 8160 | 11.1 E 5 |
| 5000 | 8900 | 9.1 E 5 |

## 12 ppg Foam CYM

| Confining Pressure | Effective Strength psi | Young’s Modules psi |
| --- | --- | --- |
| 0 | 2885 | 5.8 E 5 |
| 500 | 3950 | 6.8 E 5 |
| 1000 | 4510 | 6.1 E 5 |

## 12 ppg Bead CYM

| Confining Stress | Effective Strength psi | Young’s Modules |
| --- | --- | --- |
| 0 | 5150 | 9.5 E 5 |
| 500 | 6000 | 8.1 E 5 |
| 1000 | 6150 | 1 E 6 |

## Latex CYM

| Confining Stess | Effective Strength psi | CYM psi |
| --- | --- | --- |
| 0 | 3500 | 5.6 E 5 |
| 250 | 5250  | 8.9 E 5 |
| 500 | 6000 | 9.4 E 5 |

## Hydrostatic Cycles

- 10 ppg foam

## Acoustic Measurements

- Chandler’s New Mechanical Properties Device

## Chandler Device

| Slurry | PR | Comp. YM |
| --- | --- | --- |
| Type 1 | 0.20 | 2.3 E 6 |
| Beads | 0.31 | 1.5 E 6 |
| Latex | 0.39 | 1.4 E 6 |
| Latex/Fibers | 0.19 | 2.5 E 6 |
| Class H | 0.24 | 2.2 E 6 |
| Class H Fibers | 0.25 | 2.3 E 6 |

## Rock Mechanic Data

| Slurry | PR | Comp. YM |
| --- | --- | --- |
| Type 1 |  | 1.7 E 6 |
| Type 1 Beads |  | 9.5 E 5 |
| Type 1 Latex |  | 5.6 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

| System | Type 1 | Foam | Beads | Latex |
| --- | --- | --- | --- | --- |
| Base P | 1194 | 127/98 | 109/78 | ---- |
| Base S | 198 | 233 | 143 | 223 |
| Temp P | 165 | 299/215 | 191/269 | ---- |
| Temp S | 72 | 7 | 56 | 149 |
| Press P | 194/106 | 276/228 | 294/170 | ----- |
| Press S | 23 | 22 C | 23 C | 11 |

## Annular Seal Test Configurations

**Notes:**
The pipe-in-pipe configuration consists of a sandblasted internal pipe with an outer diameter (OD) of 1 1/16 in. and a sandblasted external pipe with an internal diameter (ID) of 3 in. and lengths of 6 in. A contoured base and top are used to center the internal pipe within the external pipe. The base extends into the annulus 1 in. and cement fills the annulus to a length of 4 in. The top 1 in. of annulus contains water. 
For the pipe-in-soft shear bonds, plastisol is used to allow the cement to cure in a less-rigid, lower-restraint environment. Plastisol is a mixture of a resin and a plasticizer that creates a soft, flexible substance. This particular plastisol blend (PolyOne’s Denflex PX-10510-A) creates a substance with a hardness of 40 duro. 

## Annular Seal Tests

| Annular Seal  | Class A | Foamed | Bead |
| --- | --- | --- | --- |
| Initial Flow- Pipe in Pipe | 0 Flow | 0 Flow | 0 Flow |
| Initial Flow- Pipe in Soft | 0 Flow | 0.5K(md) | 0 Flow |
| Temperature Cycled- Pipe in Pipe | 0 Flow | 0 Flow | 0 Flow |
| Temperature Cycled- Pipe in Soft | 0 Flow | 123K md/(2200 md) | 43K(md)(cracked during cycling) |
| Pressure Cycled- Pipe in Pipe | 0 Flow | 0 Flow | 0 Flow |
| Pressure Cycled- Pipe in Soft | 27K(md) | 0.19K (md)(cracked during cycling) | 3K(md) |

## Annular Seal Test Model

## 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