Hydraulic, Pneumatic & Fluid Power Systems worked example

Reservoir Sizing with pump flow rate of 250 units: a worked example

What does the result look like when pump flow rate reaches 250 units? The full calculation is worked below with real intermediate numbers. Use it when reservoir sizing in hydraulic, pneumatic and fluid power systems needs a few factors combined into one defensible number for hydraulic, pneumatic and fluid power systems.

The inputs for this scenario

  • Pump flow rate (GPM): 250 units (raised for this scenario; the documented default is 100)
  • Reservoir holdup time (minutes): 4 units (unchanged)
  • Volume unit conversion factor: 0.01 x (unchanged)
  • Thermal / process derating multiplier: 1 x (unchanged)

Working through the calculation

  • Applying the documented formula (Reservoir Sizing = first factor × second factor × conversion factor × process multiplier) to the inputs above produces each figure below.
  • At this operating point the engine returns 5 units for result, the number this scenario is built around.
  • At this operating point the engine returns 5 value for base product.
  • At this operating point the engine returns 1 x for multiplier.
  • At this operating point the engine returns 1,000 value for factor a x b.

How this compares with the baseline

  • Against the tool's baseline example, where pump flow rate sits at 100 units and the headline result is 2 units, this scenario comes in 150% above the baseline at 5 units.
  • A figure at this level is achievable when pump flow rate is genuinely sustained, not just peaked for a shift. It is a volumetric estimate only; it does not size for cooling capacity, baffle layout, or NPSH at the pump suction, which may demand a larger tank than volume alone suggests.

Results at a glance

  • Result: 5 units (headline result)
  • Base product: 5 value
  • Multiplier: 1 x
  • Factor A x B: 1,000 value

Run it with your numbers

  • Every input above is editable in the live Reservoir Sizing calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.