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.

Continue reading →

Cement slurry calculation (volume, density, yield) are quite simple and the basic behind is mass balance calculation. Cement calculation for common liquid and/or solid additive is pretty easy to understand. However, complex cement slurry as foam cement is almost not possible to do it by hand due to its complexity and for this case, you might need service company cement program to solve the problem. In this blog, I will write articles showing the cement calculation of common liquid and/or solid additive which you almost see every cement job on the rig.

Continue reading →