Wellbore Damage Identification Combining High-Resolution Ultrasonic Images and Time-Based Drilling Parameters

ABSTRACT: Historically, the Ringhorne field has presented challenges with wellbore instability, non-productive time, and lost sections when drilling the overburden from the drill center. To unlock new reserves and to continue to construct new extended-reach drilling (ERD) wells from the platform over the next ten years, several improvement initiatives have been introduced. To better understand the drilling challenges related to unstable formations, validate the geomechanical model, and to reduce the risks in drilling ERD wells, additional data acquisition and analysis were performed. Ultrasonic caliper, high-resolution ultrasonic images, and analysis of time-based drilling parameters were employed in a deterministic way to understand the root cause of different types of wellbore damage, focusing on identifying shear failure from the image logs. Several recommendations have come out of the project, which have been implemented in different phases of the well-delivery process. This includes recommendations on improving drilling practices, mud weight determination, casing design, bit design, and reducing uncertainties in the geomechanical model with targeted data acquisition.