WELLBORE INTEGRITY

WELL INTEGRITY

Maintaining well integrity over the lifetime of an oil and gas well begins with proper well design and construction. Casing and cement selection, coupled with proper installation, are key components to providing long-term integrity of the well.

WELL INTEGRITY

Identify components to address the expected chemical and physical environments of each well during the well design and construction process. Design and construct wells with properly engineered barrier systems

BEST PRACTICES

• Identify the objectives • Design to meet the objectives • Evaluate against the design

Core Principles • Protect groundwater and the environment

• Proper wellbore construction and installation of barriers

• Well design and construction • Ensure environmentally sound, safe production of hydrocarbons

CEMENTING DESIGN PROCESS

Successful cementing must account for best practices in design and execution:

• Understand the Chemistry of the system • Optimize the Physics of Cement Placement • Determine Well Site Logistics and Equipment Limits • Evaluate to Confirm Objectives are Met

CEMENTING DESIGN PROCESS

API Standard 65 (Part 2) • Industry accepted design best practices include:

• Industry accepted execution best practices

PRE JOB ENGINEERING

• Utilization of Pre-Job Engineering Software simulating fluid placement and pressures

• Optimized rates and volumes for cement placement • Pre-Job Laboratory Data Design of the cement slurry to meet well

requirements

PRE JOB ENGINEERING

Slurry Design • Evaluate well requirements:

• Short term - during cement placement • Long term - throughout entire well life

• Customize material usage for cement design:

• Fit-for-purpose design • Customize for each well / field

Cement design is not a “one size fits all” process

ENGINEERING SOFTWARE

Placement Modeling Temperature Modeling Wellbore Stress Analysis

PLACEMENT MODELING

Placement rates

Pipe movement

Pre-job drilling fluid circulation rates and volumes

Appropriate use of downhole tools: • Centralizers, float equipment, etc.

• Consideration for mechanical annular barriers

JOB EXECUTION PLANS

• Anticipated Pressures • Design Fluid Rates • Volumes for all fluids • Density control of spacers and cement slurries • Data Recording

EVALUATION

Data Sets Available: • Pre-job engineering, laboratory and execution • Job execution logs • Post job testing and logging

Evaluation & Verification • Should not depend on a single set of data • Consideration should be given to “as designed” and “as built”

comparisons • Combined data should be evaluated “Does It Make Sense?”

SUMMARY

Successful wellbore installation requires:

• Understanding the objectives • Identification of methods and materials to be used to

achieve the objectives • Adherence to design plans • Proper evaluation to assure objectives have been

met