The DRILPLEX AR PLUS system provides anionic tolerance in comparison with the standard version of the DRILPLEX drilling fluid system. This unique feature offers more flexibility and options to drill unconsolidated formations with potential anionic characteristics while still providing the similar unique shear thinning profile, hole cleaning potential and reduced lost circulation risks of the DRILPEX drilling fluid system.

Pretreatment with a specially selected anionic scavenger will assure protection of the bentonite-mixed-metal-oxide complex while drilling in negatively charged formations. Additionally, the system was enhanced with a specially designed fluid loss control additive to provide filtration control and further prevent wellbore instability.