**Pipe 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 in**^{2} – ID in^{2} ) ÷ 1029.4

^{2}– ID in

^{2}) ÷ 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 diplacment* such as casing and tubing. It is not for closed-end displacement. It’s 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 in

Pipe Displacement of 9-5/8” casing 40 ppf in bbl/ft = **(9.625 ^{2} – 8.835^{2} ) ÷1029.4**

Pipe Displacement of 9-5/8” casing 40 ppf in bbl/ft =

**0.01417**bbl/ft

**Please find the excel sheet how to ****calculate pipe displacement**

**Ref books: **Lapeyrouse, N.J., 2002. Formulas and calculations for drilling, production and workover, Boston: Gulf Professional publishing.

Bourgoyne, A.J.T., Chenevert , M.E. & Millheim, K.K., 1986. SPE Textbook Series, Volume 2: Applied Drilling Engineering, Society of Petroleum Engineers.

Mitchell, R.F., Miska, S. & Aadny, B.S., 2011. Fundamentals of drilling engineering, Richardson, TX: Society of Petroleum Engineers.

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Hi Dear, are you truly visiting this website regularly, if so after that

you will absolutely get fastidious knowledge.

Dears,

Good Days ,

Kindly , we need the line displacement calculation relating to distance between vessel and shore tank.

Thanks & Best Regards

R.Razavi

Ramin,

I am not familiar with the line displacement calculation relating to distance between vessel and shore tank. Sorry about this.

Shyne.

Hello,

Can you please explain where the figure 1029.4 comes from. Is tis the weight of the joint of casing?

I would like to work out the displacement for my own tools which are heavier at 44.6 lbs/ft.

Thanks.

1029.4 is conversion factor used to simplify the calculation.

wonderfull

well illustrated work

how can we calculate drilling string weight?

The string weight is calculated by this formula:

String weight (lb) = Air weight (lb/ft) x length of string (lb) x buoyancy factor

Regards,

Shyne

Important Note. This formula for unplugged pipe at the bottom.