BAKER HUGHES - Drilling Fluids Reference Manual

RESERVOIR APPLICATION FLUIDS
Reservoir Considerations
After drilling over 180 wells with the BIO-LOSE 90 system, Baker Hughes Drilling Fluids has
found this fluid system to be compatible with formation fluids. Laboratory testing is available and
return permeability tests have been conducted on this fluid system with favorable results. The
presence of an emulsification inhibitor ensures that minimal formation damage will occur as the
reservoir is penetrated.
Fluid Density
The BIO-LOSE 90 system can be maintained in a density range of 8.5 to 8.6 lb/gal if
adequate solids control equipment is available. The solids content of the fluid should be monitored
closely and if the level climbs above 2%, consideration should be given to discarding some fluid.
In most cases, Baker Hughes Drilling Fluids recommends that the hole volume be displaced with
fresh fluid every 500 to 600 ft of new hole.
Directional Tools
In the BIO-LOSE 90 system, there are no additives which could prove detrimental to the
directional drilling equipment. If a bridging agent is required, Baker Hughes Drilling Fluids
recommends the addition of various grades of calcium carbonate, which will not affect the
performance of downhole tools. Drilling fluid losses have been minimal when using the BIO-
LOSE 90 system without any bridging agent – even when drilling a carbonate zone where the
primary porosity comes from micro-fracturing.
Recommended Fluid Properties
Fluid Density
8.5 – 8.6 lb/gal
Funnel Viscosity
35 - 45 sec/qt
Yield Point 4 – 8 lb/100 ft 2
pH 7.5 - 8.0
API Filtrate
4.0 - 6.0 cc/30 min.
MILBREAK 943
0.5% - 1.0% by volume
OMNIFLOW ® DIF SYSTEM
System Benefits
The OMNIFLOW ® DIF system is a specially formulated, invert emulsion, drill-in and completion
fluid using an approved external phase oil. This system is designed to minimize formation damage
by using carefully selected surfactants at minimal concentrations to avoid emulsion blocking. MIL-
CARB bridging agent has been chosen for the system as its wide particle size distribution is suited
for bridging most reservoirs. OMNIFLOW ® DIF system’s simple formulation is designed for easy
filter cake lift off. OMNIFLOW ® DIF system’s organic continuous phase and internal phase
activity make the system ideal for long term control of sensitive shales encountered before and
while drilling the reservoir. Characteristically for an invert emulsion system, the OMNIFLOW
DIF system exhibits minimal pore-pressure penetration and is stable at high downhole
BAKER HUGHES DRILLING FLUIDS
REFERENCE MANUAL
REVISION 2006 6-36