An offshore operator in Dubai selected FLC 2000 for use in the 8 ½-in. section of a well. As a preventative approach, FLC 2000 was selected to help the operator drill without losses and fluid invasion in the depleted Mishrif zone, focusing on the low pore pressure of 2lb/gal historically found in this region.Typical mud weights in this area range from 9.5-9.7 lb/gal. Upon successful drilling of the Mishrif zone, the drilling fluid would then be weighted to control high pressure formations below – the Nahr Umr andThamana.
The drilling fluid provider designed a high-performance water-based fluid system and incorporated 6 lb/bbl of FLC 2000 through the problematic section (Mishrif zone). FLC 2000 complimented the drilling fluid properties to prevent wellbore instability, losses, and differential sticking. FLC 2000 was also used to prevent fluid invasion and fracture propagation in the depleted zones once the mud weight increases.
The 8 ½-in. section was drilled successfully without significant losses or any other drilling-related issues such as hole collapse or differential sticking. The mud weight was increased above the already high formation integrity test (FIT) of 12.3 lb/gal while using a12.5 lb/gal mud weight. The operator then drilled through the two high-pressure formations with no wellbore issues, preventing mud losses, differential sticking, and overall borehole instability.