Cementing Volume Calculator

Work out cementing volume instantly with clear inputs, formula shown and shareable results.

About Cementing Volume Calculator

Annular capacity in barrels per foot is (hole diameter squared minus casing OD squared) divided by 1029.4, with diameters in inches. Multiplying by the cemented length gives the theoretical volume, to which an excess of 20-50% is added for hole washout measured by caliper log where available.

Formulas

Annular capacity

Capacity (bbl/ft) = (D_hole^2 - D_casing^2) / 1029.4

Cement volume

Volume = capacity x cemented length x (1 + excess %)

Worked example

With the default values below, Cementing Volume Calculator returns Cement Slurry Volume of 73.40. Change any input above and every figure here is recalculated in your browser.

Inputs used

Hole Diameterminimum 0.01 inches: 8.5 inches
Casing Outside Diameterminimum 0.01 inches: 7 inches
Cemented Interval Lengthminimum 0.01 ft: 2,500 ft
Excess Allowanceaccepts 0–200 %: 30 %

Results

Cement Slurry Volume: 73.40
Theoretical Annular Volume: 56.46
Annular Capacity: 0.022586
Sacks Of Cement: 350

Step by step

1Values used
2Annular capacity
3Cement volume
4Cement Slurry Volume= 73.40
5Theoretical Annular Volume= 56.46
6Annular Capacity= 0.022586
7Sacks Of Cement= 350

Assumptions and limits

The result is derived only from the 4 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
Figures are rounded for display to 6 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
Cement volume and top-of-cement requirements are usually set by regulation for well integrity and aquifer protection. Verify against the applicable well construction rules.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Cement volume and top-of-cement requirements are usually set by regulation for well integrity and aquifer protection. Verify against the applicable well construction rules.

Frequently Asked Questions

Why is such a large excess needed?

The drilled hole is rarely to gauge — washouts in soft formations can enlarge it substantially. A caliper log lets excess be reduced to 10-20%; without one, 30-50% is prudent in open hole.

What happens if cement volume is short?

The top of cement falls below the design point, leaving the annulus uncemented. That risks loss of zonal isolation, sustained casing pressure and a costly remedial squeeze.