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Pump Pressure Exponent from Two Pump Tests Formula

n=ln(P1/P2)ln(Q1/Q2)n=\frac{\ln(P_1/P_2)}{\ln(Q_1/Q_2)}

Pump Pressure Exponent from Two Pump Tests calculates pump pressure exponent for drilling hydraulics workflows in drilling engineering.

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How engineers use this formula

Use this formula when the listed inputs (P_1, P_2, Q_1, Q_2) 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, n equals 1.87214 dimensionless.

P_1psi

2700

P_2psi

500

Q_1gpm

320

Q_2gpm

130

Inputs

P_1

psi

Circulating Pressure at Rate 1

P_2

psi

Circulating Pressure at Rate 2

Q_1

gpm

Pump Rate 1

Q_2

gpm

Pump Rate 2

Outputs

n

dimensionless

Pump Pressure Exponent

P_1

psi

Circulating Pressure at Rate 1

P_2

psi

Circulating Pressure at Rate 2

Q_1

gpm

Pump Rate 1

Q_2

gpm

Pump Rate 2

Source and review

reviewed

DrillingFormulas. Calculate Pump Pressure and Select Most Suitable Pump Exponent.

Source

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