Pump Output – Audit

Pump Output – Audit

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Mud pump outputs, release 3, issued 26 January 2010. AUDIT version.

The current release of this worksheet exists in different versions. They are identical apart from the way they are formatted. The Work version hides intermediate calculations and allows the user to see the results just below the inputs. The Audit version displays all intermediate calculations.


This worksheet takes inputs for the rig pumps and (optionally) hole and pipe sizes. It outputs pump flow rates and power, also fluid velocity if diameters entered.

User input



Pump piston diameter. L_Dpp =





Pump rod diameter (0 for triplex SA pump). L_Dpr =



Pump stroke length. Lps =



Volumetric efficiency, %. ηv =



Strokes per minute. Rω =





Pressure. Pp =







Optional for AV’s;

Drillpipe diameter. L_Ddp =



Casing ID. L_dcs =







Drillcollar diameter. L_Ddc =

Hole diameter. L_Dh =


Click here when any values are modified to update the result.


Calculate pump output per stroke; if Dpr = 0, assume duplex DA pump otherwise triplex SA pump.

Calculate pump output per minute

Calculate the output power for the SPM and pump pressure

Calculate the AV’s for the various annular clearances.


Pump output per stroke

Pump output per minute

Hydraulic horsepower

Annular velocity DP/csg

Annular velocity DP/hole

Annular velocity DC/csg

Annular velocity DC/hole

Worksheet references

Institut Francais du Petrole. Drilling Data Handbook, 6th Edition.

Release 1 of this worksheet issued on 26 March 2008.

Release 2 standardised the variable names ( see www.drillers.com/download/StandardVariableNames.doc ) and added the different AV calculations.

Release 3 corrected an error in the calculation for vol/stroke and added Bar as an optional unit for pressure.

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