High-producing deepwater well
For a high-producing deepwater well in the West Seno field, Indonesia,
Chevron needed to regain access to a perforation zone plugged by sand fill. CT
cleanout operations were attempted to remove the sand, but they had a low
success rate because of
- large casing—greater than 4.5-in ID
- high deviation angles—greater than 60°
- low BHP gradients—less than 0.3 psi/ft.
The company attempted direct circulation using gas lift, reverse
cleanout using fluid, and direct foam circulation. Respectively, these
techniques resulted in batched production, a stuck pipe incident, and high cost
due to offshore logistical limitations.