Formulas and Calculations for Drilling, Production, and Workover

Chapter Three

Drilling Fluids

Symbol	Description	Units
A	additive content	lb/bbl
B%	amount of bentonite in the mud	%
Bppb	amount of bentonite in the mud	lb/bbl
CD	volume of dilution	gal/min
CF	volume of mud feed into centrifuge	gal/min
Cl	chloride content measured from the filtrate	ppm
CO	centrifuge overflow mud weight	ppg
COM	volume fraction of mud in underflow	%
CU	centrifuge underflow volume	gal/min
CUA	mud additives in the underflow going into the mixing pit	lb/min
CUB	amount of weight material going into the mixing pit	lb/min
CUC	amount of clay in the centrifuge underflow	lb/min
CUL	volume of base liquid flow rate going into the mixing pit	gal/min
DS%	volume of drill solids	%
DSppb	amount of drill solids	lb/bbl
FCEC	CEC of the formation solids	lb/bbl
fo	fraction of base oil in mixture	decimal ...