Drilling EngineeringWell Control
Casing Pressure Increase from Stripping Into Influx Formula
Casing Pressure Increase from Stripping Into Influx calculates casing pressure increase from stripping into influx for well control workflows in drilling engineering.
How engineers use this formula
Use this formula when the listed inputs (H, G, G_i) are known and the assumptions behind the cited well control 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, P equals 34.371605 psi.
Hft
62.49382716049384
Gpsi/ft
0.65
G_ipsi/ft
0.1
Inputs
H
ftHeight Gain from Stripping Into Influx
G
psi/ftMud Gradient
G_i
psi/ftInflux Gradient
Outputs
P
psi
Casing Pressure Increase from Stripping Into Influx
H
ft
Height Gain from Stripping Into Influx
G
psi/ft
Mud Gradient
G_i
psi/ft
Influx Gradient
Source and review
reviewedLapeyrouse, N.J. Formulas and Calculations for Drilling, Production and Workover, 2nd Edition, Page 140.
Source