Pump, Compressor & Rotating Equipment Assembly worked example

Motor Sizing with load flow or torque demand of 50 units: a worked example in pump, compressor & rotating equipment assembly

Suppose load flow or torque demand falls to 50 units. This page works the full calculation at that level so you can see exactly which result moves and by how much. Motor Sizing estimates the drive power a pump or compressor needs by chaining the mechanical load, the operating duty factor, a unit-conversion constant and a service or efficiency multiplier.

The inputs for this scenario

  • Load flow or torque demand: 50 units (the input this scenario stresses; the baseline uses 100)
  • Operating factor (head, pressure or duty): 4 units (held at the documented default)
  • Unit-conversion constant to motor power: 0.01 x (held at the documented default)
  • Service factor / efficiency multiplier: 1 x (held at the documented default)

Working through the calculation

  • The calculation starts from the formula this tool documents: Motor Sizing = first factor × second factor × conversion factor × process multiplier.
  • Result works out to 1 units at these inputs, and this is the headline figure for the scenario.
  • Base product works out to 1 value at these inputs.
  • Multiplier works out to 1 x at these inputs.
  • Factor A x B works out to 200 value at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where load flow or torque demand sits at 100 units and the headline result is 2 units, this scenario comes in 50% below the baseline at 1 units.
  • It multiplies a load factor, an operating factor, a conversion constant and a process multiplier into a single motor-sizing value. When the numbers land here, the stressed input is the lever to work; the walkthrough above shows exactly how much each output recovers as it climbs back toward the baseline.

Results at a glance

  • Result: 1 units (headline result)
  • Base product: 1 value
  • Multiplier: 1 x
  • Factor A x B: 200 value

Run it with your numbers

  • To rerun this with your own numbers, open the live Motor Sizing calculator, set load flow or torque demand to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.