This topic demonstrates how to determine cement density and yield as per the cement slurry formula.
The cement formula given from town is listed below:
Cement formula:
Class G cement
35% Silica sand
0.2 gps of chemical A
0.6 gps of chemical B
4.5 gps of drill water
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
Note: 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.
The concept that you need to understand is
Volume = Weight x Absolute Volume
Where:
Volume in gal/sack
Weight in lb/sack
Absolute volume in gal/sack
Everything in cement calculation will be based on one sack of cement.
| Weight (lb/sack) | Absolute volume (gal/lb) | Volume (Gal/sack) | |
| 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 | 0.0103 | 5.825 x 0.0103 = 0.6 |
| Water | 8.33 x 4.5 = 37.485 | 1/8.33 | 37.485 x 0.12 = 4.5 |
| Total | 94+32.9+1.0267+5.825+37.485 | 3.591+1.5+0.2+0.6+4.5 |
Total weight per sack of cement =94+32.9+1.0267+5.825+37.485 = 171.2367 lb/sack
Total Volume of slurry/sack (Cement Yield) = 10.391 gal/sack
Cement Density = Total weight per sack of cement ÷ Total Volume Slurry
Cement Density = 16.5 ppg
Ref books: 
Cementing Technology Books
Formulas and Calculations for Drilling, Production and Workover, Second Edition
