Planning and Preparing for the First Subsea Field Test of a Full-Scale Dual-Gradient Drilling System

Abstract

Summary Dual-gradient drilling (DGD) is an emerging technology that will enable operators to drill in environments where mud weights are quite high and formation fracture pressures are quite low. This step-change technology will allow access to deepwater reserves and will fundamentally change the way deepwater wells are drilled. This paper describes the planning and preparation for the world's first dual-gradient well in Green Canyon 136. Our objective was to deliver a functioning and proven DGD system for commercial application in deepwater environments. The dual-gradient system worked as designed, and 100% of all critical objectives were successfully met.