Wellbore stability analysis

Overview

Avoiding mechanical failures while drilling is critical to maintaining wellbore stability through challenging formations. GaffneyCline™ energy advisory’s wellbore stability analysis services help you pinpoint the optimal mud weight window to maintain mechanical stability and ensure safer, faster drilling through your target formation.

Optimize mud weight and casing depth

We estimate the degree and likelihood of failures for a given borehole trajectory by analyzing critical parameters, including in-situ stresses, pore pressure, rock strength, and wellbore trajectory and pressure.

Through this analysis, we develop a safe operating window that defines the upper-bound mud weight constrained by the fracture gradient. The pore or mud pressure required to control the breakout width defines the lower-bound limit.

With a clear understanding of this operating window, you can optimize your drilling and completion strategies for greater mechanical stability. Specific deliverables include:

• Mud weight window as a function of depth
• Recommended interval mud weights and casing setting depths
• Wellbore sensitivity to mud weight fluctuations
• Quantitative risk assessments (QRAs)

Push the boundaries of your mud program

Our wellbore stability analysis also includes evaluations of fracture initiation, link-up, and growth pressures to assess the possibility of extending the upper-bound mud weight. And with lower hemisphere stereographic plots created at critical points along the well, you’ll get a global view of the most stable wellbore trajectory. This information is beneficial in deciding the location of a drilling pad/platform or optimizing the wellbore trajectory for ECD management.

Minimize drilling risks through difficult formations

Drilling complex wellbores through trouble zones can lead to geological uncertainties, long openhole exposure times, fluid-penetration issues, and weak-plane failures. GaffneyCline energy advisory’s experts conduct advanced wellbore stability and drilling history analyses to:

• Address instability issues while drilling
• Evaluate additional risk factors such as temperature effects
• Help select the optimal type, density, and composition of drilling fluids
• Optimize wellbore trajectories and hole cleaning, tripping, and reaming practices
• Develop optimal casing programs integrating geomechanics, wellbore strengthening, and ECD management

Contact your Baker Hughes representative to learn how GaffneyCline energy advisory’s wellbore stability analysis can help you ensure mechanical stability and optimize drilling performance through your most challenging formations.

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Wellbore Stability Analysis [Left] A mud weight window assuming isotropic rock strength, which provides the basis for selecting the casing setting depths. [Right] A mud weight contour plot (lower hemi-sphere stereographic projection) showing the effect.

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[Left] Time-dependent wellbore failure simulation showing the effect of fluid penetration on the stability of the wellbore. [Right] Drilling through fault analysis showing the risk of borehole instability when crossing a fault. This analysis helps to identify the most optimal wellbore trajectory on both sides of the fault considering the effects of weak-bedding plane, stress rotation, etc.