Increase Mudweight - Audit

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Increase mudweight, release 2, issued 2 July 2008. AUDIT version.

The current release of this worksheet exists in 3 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. This is useful for quick “what-if” games, changing various inputs to see what works best. The Audit version displays all intermediate calculations. The PDA version removes all text and formats the input and output fields for optimum viewing on a mobile, small-screen device.


This worksheet takes inputs of current and desired mudweight, type of weighting material used and the volume to treat. It calculates the weighting material requirements and the resulting mud volume increase.

User input




psi/ftSG or kg/lppgkPa/mlb/ft3lb/bbl

Initial mud SG. Jmudsg1 =




psi/ftSG or kg/lppgkPa/mlb/ft3lb/bbl

Desired mud SG. Jmudsg2 =


Hematite, SG 5.0Baryte, SG 4.2CaCo3, SG 2.5Galena, SG 7.5Enter manually



Select a weighting material. Jwmsg =

or enter SG

after selecting “manual” from the drop down list.





Volume of mud to weight up. Vmudact =


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

Input values

Initial and final mud SG.

SG of weighting material.

Volume to weight up.


Calculate the mass of additive required per m3 of mud.

Calculate total amount of additive required

Calculate the new volume of mud


Weighting material per unit volume

Total weighting material

New mud volume after treatment

Worksheet references

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

MI. Drilling Fluids Handbook MI-0020 6/97.

Release 1 of this worksheet issued on 27 March 2008 by Steve Devereux.

Release 2 uses the DDC standard variable names and corrects the units used.

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