Calculation of Pump Head

Pump Head Equation:

\[ Head (ft) = \frac{Discharge\ Pressure - Suction\ Pressure}{SG \times 0.433} \]

Pump Head:

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1. What is Pump Head Calculation?

Pump head calculation determines the total dynamic head that a pump must generate to move fluid through a system. It represents the energy imparted to the fluid by the pump, expressed in feet of fluid column.

2. How Does the Calculator Work?

The calculator uses the pump head equation:

\[ Head (ft) = \frac{Discharge\ Pressure - Suction\ Pressure}{SG \times 0.433} \]

Where:

\( Discharge\ Pressure \) — Pressure at pump discharge (psi)
\( Suction\ Pressure \) — Pressure at pump suction (psi)
\( SG \) — Specific gravity of the fluid (unitless)
\( 0.433 \) — Conversion factor from psi to feet of water

Explanation: The equation converts pressure difference to equivalent head in feet, accounting for the fluid's specific gravity.

3. Importance of Pump Head Calculation

Details: Accurate pump head calculation is essential for proper pump selection, system design, energy efficiency optimization, and ensuring adequate flow rates in piping systems.

4. Using the Calculator

Tips: Enter discharge and suction pressures in psi, specific gravity as a unitless value. Ensure specific gravity is greater than zero for valid calculation.

5. Frequently Asked Questions (FAQ)

Q1: What is specific gravity and how do I find it?
A: Specific gravity is the ratio of fluid density to water density. For water, SG=1.0. For other fluids, consult material safety data sheets or engineering references.

Q2: Why is the conversion factor 0.433?
A: 0.433 psi/ft is the pressure exerted by a 1-foot column of water, derived from the density of water and gravitational acceleration.

Q3: What if suction pressure is higher than discharge pressure?
A: This would result in negative head, indicating flow reversal or measurement error. Normally, discharge pressure should exceed suction pressure.

Q4: Does this calculation include friction losses?
A: This calculation provides the head from pressure difference only. Total dynamic head should include friction losses, elevation changes, and velocity head.

Q5: When should I use this calculation?
A: Use for pump performance verification, system troubleshooting, and when pressure measurements are available but head information is needed for pump curves.