1. What is the Pump Horsepower Equation?

The pump horsepower equation calculates the power required to move a fluid through a system. It considers flow rate, head, specific gravity, and pump efficiency to determine the mechanical power needed.

2. How Does the Calculator Work?

The calculator uses the pump horsepower equation:

Where:

• \( Q \) — Flow rate (gallons per minute)
• \( H \) — Total head (feet)
• \( SG \) — Specific gravity (unitless)
• \( \eta \) — Pump efficiency (decimal)
• 3960 — Conversion constant

Explanation: The equation calculates the theoretical power required to move fluid, then divides by efficiency to get actual power requirement.

3. Importance of Pump Horsepower Calculation

Details: Accurate horsepower calculation is essential for proper pump selection, motor sizing, energy consumption estimation, and system design optimization.

4. Using the Calculator

Tips: Enter flow rate in gpm, head in feet, specific gravity (1.0 for water), and efficiency as decimal (0.0-1.0). All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is specific gravity?
A: Specific gravity is the ratio of fluid density to water density at 4°C. Water has SG = 1.0.

Q2: What is typical pump efficiency?
A: Pump efficiency typically ranges from 0.5 to 0.85 (50-85%) depending on pump type and size.

Q3: Why is the constant 3960 used?
A: 3960 is a conversion factor that combines unit conversions for gpm, feet, and horsepower.

Q4: Does this include motor efficiency?
A: No, this calculates pump hydraulic horsepower. For motor sizing, divide by motor efficiency.

Q5: Can this be used for all pump types?
A: This equation is generally applicable to centrifugal pumps. Positive displacement pumps may require different calculations.