Enter the hole diameter, casing diameter, and casing length into the calculator to determine the annular casing capacity.

Casing Capacity (Annular Volume) Calculator

Enter all values to calculate the Casing Capacity

Casing Capacity Formula

The following equation is used to calculate a casing capacity between hole and casing.

AC = (Dh^2 - ODc^2) / 1029.4 * L 
  • Where AC is the annular capacity/casing capacity (bbls (barrells))
  • Dh is the hole diameter (in)
  • ODc is the casing/pipe outer diameter (in)
  • L is the length (ft)

What is a casing capacity?

Definition:

A casing capacity, more commonly known as annular volume, is a term used in oil drilling to describe the total volume between the casing and the hole wall.

How to calculate casing capacity?

Example Problem:

The following example outlines how to calculate a casing capacity.

First, determine the hole diameter. In this example, the hole diameter is 8 inches.

Next, determine the casing diameter. For this problem, the pipe diameter is 5 inches.

Next, determine the length. The length of the hole is 5000 feet.

Finally, calculate the casing capacity using the formula above:

AC = (Dh^2 – ODc^2) / 1029.4 * L

AC = (8^2 – 5^2) / 1029.4 * 5000

AC = 189.4 bbls