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Calculate Total Bulk Cement and Water Required

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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

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Calculate Cement Density and Yield Based on Cement Formula

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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

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Calculate Water Requirement and Cement Yield as per Cement Slurry

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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

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Drilling Formula Calculation Sheet V1.1

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I update some useful drilling formulas into the drilling formulas spread sheet called version 1.1.

Please feel free to download.

Drilling Formula Calculation Sheet V1.1

The following drilling formulas are added:

Calculate Influx Height

Hydrostatic Pressure Loss Due to Gas Cut Mud

Kill Weight Mud

Maximum pit gain from gas kick in water based mud

Maximum Surface Pressure from Gas Influx in Water Based Mud

You can read how to use this work sheet via this topic > Drilling Formula Calculation Sheet

Ref book: Drilling Formula Book Formulas and Calculations for Drilling, Production and Workover, Second Edition

Calculate Cement (Oil Well Cement) Volume Required

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Cement volume calculation is based on annular capacity multiplied by length of cement as per cement program. This topic will demonstrate you how to determine cement volume as per specification and displace volume. After reading and understanding the concept, you will be able to apply to your cement job.

The knowledge required: annular capacity and inner capacity of cylindical object

 

Well information:

Well is drilled with 8.5 inch bit to 9,015 MD/8,505 TVD with oil based mud (9.5 ppg). Estimated hole sized based on an open hole log is 8.6 inch.

Previous casing size is 9-5/8” and its shoe is at 6,500 MD/5000’TVD.

Plan to run 7” casing and planned shoe depth at 9,000’MD/8,500’TVD.

There is one float collar at 8960’MD/8470’ TVD.

Top of cement is 2000 ft above 9-5/8” casing.

Spacer volume is from top of cement to surface.

Casing information

7” casing ID = 6.185”

9-5/8” casing ID = 8.85”

Use hole size measured from the open hole log to determine cement volume.

The well schematic should look like this.

 

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