Pipe Displacement Calculation

Pipe Displacement CalculationPipe displacement, normally in bbl/ft, is steel volume to displace fluid volume. When we either pull out of hole or trip in hole for any kind of pipes such as drill pipe, casing or tubing, you should know how much fluid to displace steel volume.

For example, when we pull out of hole, a trip sheet must be monitored all time. We must know how much fluid will fill the hole each stand of drill pipe pulled out. If the volume of displacement less than theoretical displacement value, we may have problem due to swabbing formation into wellbore.

This post will demonstrate how to calculate plain pipe displacement with this following formula:

Pipe Displacement in bbl/ft = (OD in2 ID in2 ) 1029.4

Where,OD is out side diameter of pipe in inch.ID is inside diameter of pipe in inch.

This formula is good for plain pipe displacment such as casing and tubing. Its not accurate enough for drill pipe because this formula does not account for tool joint displacement therefore you need drill pipe specification sheet for its displacement.

Example: Determine pipe displacement in bbl/ft of 9-5/8 casing 40 ppf, OD = 9.625 in, ID = 8.835 inPipe Displacement of 9-5/8 casing 40 ppf in bbl/ft = (9.6252 8.8352 ) 1029.4Pipe Displacement of 9-5/8 casing 40 ppf in bbl/ft = 0.01417 bbl/ft

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