Drilling EngineeringDrilling Operations and Economics
Rotary-Speed Drill-Rate Model Penetration Rate Formula
Rotary-Speed Drill-Rate Model Penetration Rate calculates penetration rate for drilling operations and economics workflows in drilling engineering.
How engineers use this formula
Use this formula when the listed inputs (K_p, N, a_N) are known and the assumptions behind the cited drilling operations and economics 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, R equals 54.772256 ft/h.
K_pempirical
5
Nrev/min
120
a_Ndimensionless
0.5
Inputs
K_p
empiricalRotary-speed drill-rate coefficient
N
rev/minBit rotary speed
a_N
dimensionlessRotary-speed exponent
Outputs
R
ft/h
Penetration rate
K_p
empirical
Rotary-speed drill-rate coefficient
N
rev/min
Bit rotary speed
a_N
dimensionless
Rotary-speed exponent
Source and review
reviewedAdvanced Well Control, Watson, D., Brittenham, T., Moore, P.L. (2003)
Watson, D., Brittenham, T., and Moore, P.L. 2003. Advanced Well Control, Vol. 10, Society of Petroleum Engineers, Page 49.
source conflict
Source