Drilling EngineeringDrilling Hydraulics
Duplex Pump Output Rate with Volumetric Efficiency Formula
Duplex Pump Output Rate with Volumetric Efficiency calculates pump output rate for drilling hydraulics workflows in drilling engineering.
How engineers use this formula
Use this formula when the listed inputs (D_l, d_r, S, E_v, SPM) are known and the assumptions behind the cited drilling hydraulics 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, Q_gpm equals 377.540352 gpm.
D_lin
6
d_rin
2
Sin
12
E_vfraction
0.85
SPMstrokes/min
80
Inputs
D_l
inLiner Diameter
d_r
inRod Diameter
S
inStroke Length
E_v
fractionVolumetric Efficiency
SPM
strokes/minPump Speed
Outputs
Q_gpm
gpm
Pump Output Rate
D_l
in
Liner Diameter
d_r
in
Rod Diameter
S
in
Stroke Length
E_v
fraction
Volumetric Efficiency
SPM
strokes/min
Pump Speed
Source and review
reviewedLapeyrouse, N.J. 2002. Formulas and Calculations for Drilling, Production and Workover, 2nd Edition, Page 9; AAPG Wellsite Math pump-output conversions.
Source