BAKER HUGHES - Drilling Fluids Reference Manual

TABLE OF CONTENTS
HOLE CLEANING TOOLS & TECHNIQUES
Riser booster pumps, i.e., pumps assigned solely to circulate the marine riser, are used to increase the
flow rate in the marine riser and so enable efficient cuttings transport in the riser. Riser booster pumps
commonly increase the flow rate in the annulus by 500 gallons per minute. This increase in the flow
rate in the riser has a negligible effect on ECD due to the low pressure drop in the riser. Riser booster
pumps are necessary due to the often dramatic diameter changes at the riser. This is most marked in
12 ¼” and smaller hole diameters. The ADVANTAGE SM engineering software allows the user to
evaluate the effectiveness of various riser boost rates
The same basic principles for hole cleaning are as valid in deepwater as in all drilling operations. The
recommended method to evaluate hole cleaning is by use of the hole cleaning model within
ADVANTAGE SM . If the HPHT mode is selected in ADVANTAGE SM and the requisite temperature
gradients, PVT of the base oil and Fann® 70/75 data are provided, ADVANTAGE SM will perform
the hole cleaning analysis using downhole rheological properties.
BARITE SAG
Barite sag is as much an issue in deepwater wells as all other wells. Barite sag is a genuine risk as
efforts are made to minimize rheological properties in order to minimize ECD and minimize cold
water rheological properties. Care must be taken to avoid barite sag when reducing and
recommending rheological properties.
ECD MANAGEMENT
On many deepwater wells effective ECD management is one of the main factors in the successful
drilling of a well. This often involves running the rheological properties as low as possible without
causing hole cleaning or barite sag problems. The correct way to do this is by continual use of the
engineering software in ADVANTAGE SM , taking regular samples for Fann® 70/75 testing and
confirming that the low shear viscosity is sufficient to minimize the risk of barite sag.
ECD optimization should always be one of the steps during well planning, using planned well
geometries and fluid properties. ADVANTAGE SM Engineering is the correct tool for this type of
work.
Recommending, and implementing, good drilling practices is an integral part of ECD management.
These include controlling rates of penetration, short trips, tripping rates, casing running speeds,
methods for initiating circulation and drilling fluid properties.
BAKER HUGHES DRILLING FLUIDS
REFERENCE MANUAL
REVISION 2006 13-25