Weatherford completes novel cased-hole sidetrack in ultra-deep Gulf of Mexico waters

HOUSTON –Weatherford announced a success in an ultra-deepwater Gulf of Mexico operation that saved a major international oil company 14 rig days valued at approximately $14 million. By sidetracking from a collapsed expandable liner, the re-entry operation eliminated the time and cost associated with re-drilling and re-casing a 3,000-foot hole, resulting in the industry’s first-ever cased-hole sidetrack completed using a whipstock system in a 13 3/8-inch expandable liner.

The IOC requested off-the-shelf options that would enable sidetracking from the collapsed liner while limiting flow rates and pressures. Weatherford quickly responded and was selected to deploy its Shallow-Angle QuickCut casing-exit system with MultiCatchanchor as an available solution. The system enabled installing a window in the 13 3/8-inch expandable liner and allowing a 13 1/2-inch drilling BHA and 12 1/4-inch casing to pass the whipstock without issue. Two additional milling BHAs were used to open the window to the full OD. A total of 16 mills were shipped, nine of which had custom ODs and were used during the operation.

Throughout the operation, the Shallow-Angle QuickCut system maintained a low dogleg and smoothly transitioned from the main bore to the sidetrack, all while minimizing risks associated with thin-wall liners and channeled cement.

“When other oilfield service companies failed to provide a timely solution, Weatherford stepped in, saving this operator two weeks of rig time and millions of dollars in operating expense,” said Mark Swift, President, Western Hemisphere, Weatherford. “Installing casing exits in unique applications, such as deep expandable liners, limits the amount of nonproductive time in contingency scenarios.”