Drilling EngineeringWell Control
Bullheading Maximum Initial Surface Pressure Formula
Bullheading Maximum Initial Surface Pressure calculates maximum initial surface pressure for well control workflows in drilling engineering.
How engineers use this formula
Use this formula when the listed inputs (P_frac, P_h_init) 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_surf_init_max equals 2,600 psi.
P_fracpsi
6400
P_h_initpsi
3800
Inputs
P_frac
psiFormation Fracture Pressure
P_h_init
psiInitial Hydrostatic Pressure
Outputs
P_surf_init_max
psi
Maximum Initial Surface Pressure
P_frac
psi
Formation Fracture Pressure
P_h_init
psi
Initial Hydrostatic Pressure
Source and review
reviewedIADC WellSharp Formula Sheet, field units, well completion/workover bullheading formulae.
Source