Annular Volume Calculation & Capacity Tables.
Annular capacity volume can be defined as the volume contained between the outside of the pipe and the open hole (Fig. 1) or between the outside of the drill pipe or tubing and the inside of the casing (Fig. 2). Annulus Capacity volumes calculation might be estimated by a formula calculating the cross-sectional area between the open hole or casing ID and the drill pipe OD and then by multiplying it to its length.
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