This topic will teach you how to determine total bulk cement and water for required cement volume.

**Let’s learn from the example. **

The calculated cement volume is **150** bbl. (Learn about cement volume calculation -> **Calculate Cement (Oil Well Cement) Volume Required**

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

0.9 gps of chemical C

Required cement density = 15.9 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

Chemical C = 0.112 gal/lb

Determine total **bulk cement** and **water requirement** for **150** bbl of cement.

We still use the same concept as previous calculation:

**Volume = Weight x Absolute Volume**

Where:

Volume in gal/sack

Weight in lb/sack

Absolute volume in gal/sack

**Firstly**, we need to know how much volume of water per sack of cement.

The table below shows 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 | 0.1 ÷ 0.0974 = 1.0267 | 0.0974 | 0.2 |

Chemical B | 0.6 ÷ 0.103 = 5.825 | 0.0103 | 0.6 |

Chemical C | 0.9 ÷ 0.112 = 8.036 | 0.112 | 0.9 |

Water | 8.33 x k | 1/8.33 | k |

Total | 94+32.9+1.0267+5.825 +8.036 + (8.33k) | 3.591+1.5+0.2 +0.6+ 0.9 + k |

k is a variable for water requirement.

Total weight per sack of cement =94+32.9+1.0267+5.825+8.036+8.33k = 141.7877 + 8.33k

Total volume of cement slurry per sack of cement= 3.591+1.5+0.2+0.6+ 0.9 + k = 6.791 + k

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

15.9 = (141.7877 + 8.33k) ÷ (6.791 + k)

Solve for k: k = 4.466

The water requirement is 4.466 gal/sack.

Yield of cement = 6.791+4.466 = 11.257 gal/sack

Total cement volume is 150 bbl.

Convert bbl into gal by multiplied by 42 (1 bbl = 42 gallon)

150 bbl = 150 x 42 = 6,300 gallon

**Determine total sacks of cement requires with this following equation.**

Total sack of cement = Total Volume of Cement ÷ Yield of Cement

Where;

Total sack of cement is in sack.

Total volume of cement is gallon.

Yield of cement is gal/sack.

**Total sack of cement = 6300 ÷ 11.257 = 560 sacks.**

**Determine total of water by this relationship.**

Total water = water requirement x Total sack of cement

Where;

Total water in gallon

Water requirement in gps (gallon per sack)

Total of cement is sack

Total water = 4.466 x 560 = 2501 gal.

You can convert to bbl by divided by 42.

**Total water = 2501 ÷ 42 = 59.5 bbl.**

**Ref books: **Lapeyrouse, N.J., 2002. Formulas and calculations for drilling, production and workover, Boston: Gulf Professional publishing.

Bourgoyne, A.J.T., Chenevert , M.E. & Millheim, K.K., 1986. SPE Textbook Series, Volume 2: Applied Drilling Engineering, Society of Petroleum Engineers.

Mitchell, R.F., Miska, S. & Aadny, B.S., 2011. Fundamentals of drilling engineering, Richardson, TX: Society of Petroleum Engineers.