Case Study: Tullow Oil achieves improved zonal isolation and reduced waiting time with SLB CemFIT Shield

Tullow Ghana Ltd. Improves Zonal Isolation and Reduces Waiting Time in Long, Deviated Deepwater Wells

Tullow Oil was struggling with zonal isolation in highly deviated deepwater wells offshore West Africa, where poor cement bonding, mud channeling, narrow pressure windows, and high-permeability sandstone made cementing difficult. SLB supported the project with its CemFIT Shield mud-sealing cement system to address issues in wells across the Jubilee and TEN fields.

SLB deployed CemFIT Shield in a well with reservoir sands separated by less than 20 m, helping reduce mud mobility and prevent communication along channels after cementing. The well was pressure-cycled within 10 days and logged 12 days after cementing, and the log showed the zonal isolation requirements were achieved with no significant continuous channels, dry microannuli, or debonding, allowing Tullow Oil to reduce waiting time versus earlier wells that had required logs delayed up to 60 days.

Tullow Oil

Ian Whyte

Group Operations Petrophysics Lead