BAKER HUGHES - Drilling Fluids Reference Manual

Baker Hughes Drilling Fluids
Salt Component
Potassium chloride, sodium chloride or formates – various salts for adjusting the system’s water
activity coefficient to match that of the shale being drilled. Local environmental regulations
should be consulted when selecting a salt.
• Biopolymers - rheological control is achieved using biopolymers such as XAN-PLEX.
• Potassium Carbonate - a source of K + ions for additional shale inhibition and alkalinity
control (eliminating the need for caustic soda at the wellsite).
Supplementary Products
Several supplementary products can be used to enhance the performance of the AQUA-DRILL
system. Applications include:
• dynamic filtration control
• drilling or running casing through depleted zones
• improved rates of penetration and reduced bit-balling
• enhanced lubricity for drilling highly-deviated wells
• spotting applications.
AQUA-MAGIC ®
AQUA-MAGIC ® is a chemically-modified glycol-based material designed for all types of waterbase
drilling fluids. AQUA-MAGIC additions are recommended whenever differential sticking
may occur, especially while drilling high-angle wells.
AQUA-MAGIC is added at a concentration of 2 - 4% by volume, when running casing through
depleted zones. It is recommended to spot 10% by volume in the open hole through the zone.
Inhibition Mechanisms
Figure 3-15 illustrates how the addition of a glycol (AQUA-COL) improves the inhibition of a
water-base fluid system. The inhibition mechanisms related to the AQUA-DRILL system can be
divided into three components.
• Pore pressure transmission
• Capillary effects
• Cloud point behavior
Baker Hughes Drilling Fluids
Reference Manual
Revised 2006 3-71