Choose a displacement, dimension, flow, speed, or stroke-count calculation. Efficiency is optional and defaults to an ideal 100%; use a measured or manufacturer-supported value. For volume-to-strokes, an optional positive speed adds a time estimate.

Theoretical displacement for one single-acting cylinder. A petroleum barrel is 42 US gallons.

Type a size or choose a suggested liner size. Unit changes convert the value.

Type a length or choose a suggested size. Unit changes convert the value.

Related Calculators

Barrels Per Stroke Formula

BPSโ‚ & โ‰ˆ 0.00008095 DยฒS \ BPSโ‚ƒ & = 3 BPSโ‚ โ‰ˆ 0.0002429 DยฒS \ BPSโ‚… & = 5 BPSโ‚ โ‰ˆ 0.0004048 DยฒS

Variables:

  • BPS1 is the single-cylinder barrels per stroke (bbl/stroke)
  • BPS3 is the total barrels per stroke for a triplex pump (3 pistons) (bbl/stroke)
  • BPS5 is the total barrels per stroke for a quintuplex pump (5 pistons) (bbl/stroke)
  • D is the diameter (in)
  • S is the stroke length (in)

To calculate theoretical single-cylinder Barrels Per Stroke, use ฯ€ ร— Dยฒ ร— S รท 38808 with D and S in inches. The rounded coefficient is approximately 0.00008095. For single-acting triplex and quintuplex pumps, multiply by 3 and 5 respectively for one discharge stroke per cylinder per counted pump cycle. Use a consistent cycle definition with SPM; this model does not cover double-acting rod displacement.

How to Calculate Barrels Per Stroke?

The following steps outline how to calculate the Barrels Per Stroke.

  1. First, determine the diameter (in). 
  2. Next, determine the stroke length (in). 
  3. Next, gather the formula from above (single-cylinder) = BPS1 = ฯ€*D^2*S/38808.
  4. Finally, calculate the Barrels Per Stroke.
  5. After inserting the variables and calculating the result, check your answer with the calculator above.

Example Problem : 

Use the following variables as an example problem to test your knowledge.

diameter (in) = 7.50

stroke length (in) = 6.0. The theoretical single-cylinder result is approximately 0.02732136 bbl/stroke.

Frequently Asked Questions

What is the significance of calculating Barrels Per Stroke in mechanical systems?

Calculating Barrels Per Stroke (BPS) is crucial in mechanical systems, especially in the oil and gas industry, as it helps in estimating the theoretical volume of fluid displaced by a piston in a single stroke. This measurement is essential for sizing and comparing pump capacity; actual delivered volume will depend on factors like volumetric efficiency and operating conditions.

How does the diameter of a piston affect the Barrels Per Stroke?

The diameter of a piston directly influences the Barrels Per Stroke since a larger diameter results in a greater area for the piston to act upon, thus displacing more volume per stroke. The relationship is quadratic, meaning that even small increases in diameter can significantly increase the BPS.

Can the Barrels Per Stroke formula be used for any type of fluid?

Yes. The formula gives the pump/cylinderโ€™s geometric (theoretical) displacement and is independent of fluid type. However, the actual delivered volume can vary with volumetric efficiency due to compressibility, slippage, viscosity effects, and flow resistance.

Is it possible to increase the efficiency of a pump by adjusting the stroke length?

Changing stroke length changes pump displacement per stroke. For a required flow rate, a longer stroke can sometimes allow a lower pump speed (SPM), which may reduce some losses; however, overall efficiency depends on the pump design, operating conditions, and mechanical limits.