Drilling EngineeringDrillstring and Rig Mechanics

Drillstring Buoyancy Factor from Mud Weight Formula

BF=\frac{65.5-MW}{65.5}

Drillstring Buoyancy Factor from Mud Weight calculates buoyancy factor for drillstring and rig mechanics workflows in drilling engineering.

Calculate

How engineers use this formula

Use this formula when the listed inputs (MW) are known and the assumptions behind the cited drillstring and rig mechanics relationship match the engineering case being checked.

Assumptions

Input values are representative for the well, reservoir, fluid, or equipment case being evaluated.
The declared units match the field-unit constants used in the formula.
The cited formula applies to the selected petroleum engineering workflow.

Limitations

The calculation does not replace a full engineering model or operating procedure.
Accuracy depends on the source correlation, assumptions, input quality, and unit consistency.

Common mistakes

Mixing unit systems without converting the inputs.
Using default example values as field recommendations.
Applying the formula outside the source assumptions.

Default example

Using the default inputs, BF equals 0.816794 dimensionless.

MWppg

Inputs

MW

ppg

Mud weight

Outputs

BF

dimensionless

Buoyancy factor

MW

ppg

Mud weight

Source and review

reviewed

Formulas and Calculations for Drilling, Production and Workover, Lyons, W.C., Carter, T., Lapeyrouse, N.J. (2012)

Lyons, W.C., Carter, T., and Lapeyrouse, N.J. 2012. Formulas and Calculations for Drilling, Production and Workover, 3rd Edition, Gulf Professional Publishing, Page 24.

Source