3. Drilling Fluids

Table of Content

1. Increase Mud Weight
2. Dilution
3. Mixing Fluids of Different Densities
4. Oil Based Mud Calculations
5. Solids Analysis
6. Solids Fractions
7. Dilution of Mud System
8. Displacement - Barrels of Water/Slurry Required
9. Evaluation of Hydrocyclone
10. Evaluation of Centrifuge

3.8 Displacement - Barrels of Water/Slurry Required

$\text{Vwm}=\frac{\mathrm{Vm}\times (\mathrm{Fct}-\mathrm{Fcop})}{(\mathrm{Fct}-\mathrm{Fca})}$

where Vwm = barrels of mud to be jetted and water or slurry to be added to maintain constant circulating volume:

Example: 1000 bbl in mud system. Total LGS = 6%. Reduce solids to 4%:

Solution:
Vwm = 1000 bbl × (6 − 4) ÷ (6 − 0)
Vwm = 1000 bbl × 2 ÷ 6
Vwm = 333 bbl
If displacement is done by adding 2% bentonite slurry, the total volume would be:
Vwm = 1000 bbl × (6 − 4) ÷ (6 − 2)
Vwm = 1000 bbl × 2 ÷ 4
Vwm = 500 bbl

⬆ Table of Content