The introduction of cloud point glycols (AQUADRILL®), aluminum complexes (ALPLEX®) and finally sealing polymers (MAX-SHIELDTM) by Baker Hughes Drilling Fluids has greatly improved the osmotic effectiveness of water-based drilling fluids. PERFOMAXSM is BHDF's 3rd generation highperformance water-based drilling fluid specifically designed to emulate the drilling performance characteristics of emulsion systems.

Drilling shales can result in a variety of problems from washout to complete hole collapse. Shales make up over 75% of the drilled formation and over 70-90% of the borehole problems are related to shale instability. In the past, oil-based muds (OBM) have been the preferred choice for drilling argillaceous formations.

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