Curing seepage and partial mud losses
A deepwater operator planned to drill to select targets and sample the reservoir before running a 7 5/8-in production liner. However, a geological analysis showed the presence of localized weak interfaces along bedding planes that were most likely exacerbated by depletion and mud losses. The fracture widths were estimated to range from 1,500 to 3,000 um.
Designing appropriate slurry
Making use of the proprietary OPTI-STRESS software packages and the LCM slurry calculator plus offset formation data, various LCM slurries to cover the expected fracture width range were designed and validated in the laboratory with the advanced slot tester. The modeled blends containing Grande-Seal particulates showed a successful and quick initial bridging efficiency and stable sealing capacity up to 4,000 psi [276 bar] in the expected fracture range. Upon review of the results with the operator, the material was shipped out to the rig and the LCM plan was put in place.