Calculate Water Requirement and Cement Yield as per Cement Slurry

This topic will teach you how to determine water requirement (gal/sack) and yield of cement (gallon/sack) as per cement slurry program.


The cement formula given from town is listed below:


Cement formula:

Class G cement

35% Silica sand (35% by weight of cement)

0.2 gps of chemical A

0.6 gps of chemical B

Required cement density = 15.5 ppg

The absolute volume of each material is listed below:


Class G cement = 0.0382 gal/lb

Silica sand = 0.0456 gal/lb

Chemical A = 0.0974 gal/lb

Chemical B = 0.103 gal/lb


Determine requirement (gal/sack), yield of cement


We still use the same concept as previous calculation:


Volume = Weight x Absolute Volume



Volume in gal/sack

Weight in lb/sack

Absolute volume in gal/lb


We can create table showing each component of cement slurry as shown below:


Weight (lb/sack) Absolute volume (gal/lb) Volume (Gal/sack)
1 sack of class G cement 94 0.0382 94 x 0.0382 = 3.591
35% Silica sand 0.35 x 94 = 32.9 0.0456 32.9 x 0.0456 = 1.5
Chemical A 0.2 ÷ 0.0974 = 2.053 0.0974 2.053 x 0.0974 = 0.2
Chemical B 0.6 ÷ 0.103 = 5.825 0.103 5.825 x 0.103 = 0.6
Water 8.33 x k 1/8.33 k
Total 94+32.9+1.0267+5.825+(8.33k) 3.591+1.5+0.2+0.6+k

where; k is the variable that must be solved.

Total weight per sack of cement =94+32.9+1.0267+5.825+8.33k = 133.7517 + 8.33k

Total volume of cement slurry per sack of cement = 3.591+1.5+0.2+0.6+k = 5.891 + k

Cement Density = Total weight per sack of cement ÷ Total volume of cement slurry

15.5 = (133.7517 + 8.33k) ÷ (5.891 + k)

Solve for k: k = 5.92

After k is solved, you will get water requirement and cement yield.

The water requirement is 5.92 gal/sack.

Yield of cement = 5.891 + 5.92 = 11.811 gal/sack

Ps: I did not give you the product name in this topic or anything related to any cementing companies because I want you to understand the calculation concept. If you understand the concept, everything will be good.

Cementing Technology Books

Drilling Formula BookFormulas and Calculations for Drilling, Production and Workover, Second Edition

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6 Responses to Calculate Water Requirement and Cement Yield as per Cement Slurry

  1. Himesh says:

    how to calculated absolute volume?

  2. mohammadreza says:

    You have a mistake.Absolute volume is in gal/lb, but in top of the table it is in gal/sack

  3. shubham says:

    You have written Absolute Volume (.0103) of chemical B in table, which is not so what you have listed above (.103). Why?

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