SHELL OFFSHORE - APPLICATIONS HELPS MAINTAIN WELLBORE INTEGRITY IN NARROW MARGIN, AVOIDING TWO WEEKS OF NPTDownload PDF
WELLBORE INTEGRITY IN NARROW MARGIN
PREPARING TO NAVIGATE THE NARROW MARGIN
Planning was critical to minimize operational risks and optimize drilling efficiency in this MPD and MPC job for Shell. Halliburton worked closely with Shell to generate detailed modeling and develop a thorough execution plan for successful navigation through the narrow margins expected. By adjusting the static mud weight, at times up to one pound per gallon under the conventional drilling target weight, the MPD crew had the surface pressure flexibility to manipulate bottomhole pressure (BHP) and confidently maintain borehole stability. The plan also included a strategy for staying within the BHP window during tripping in and out of the hole, and for running casing and cementing operations. Employing the patented surge and swab pressure compensation feature during tripping pipe and, more importantly, while running the 9-5/8-in liner into the open hole, maintained a constant BHP in these critical operations. Additionally, a dual gradient tripping strategy of spotting a highly viscous pill with a heavier kill mud on top allowed operations to keep the lighter mud in the hole, without needing to displace the entire system to kill weight mud. This approach saved time and ensured the proper BHP while tripping pipe and while switching from drilling to cementing operations.
weeks of NPT avoided
wells batch drilled
Utilizing highly experienced and competent crews, along with the right technology, Halliburton and Shell collaborated to successfully execute a safe drilling campaign. Halliburton helped the operator avoid two weeks of NPT related to borehole stability, reservoir influxes, and losses, controlling the BHP at the critical point in the well during drilling operations, including tripping and running, and cementing the liner. This operation for Shell in Asia Pacific, paves the way for similar operations in this region and beyond.