1. What is the Pump Horsepower Formula?

The pump horsepower formula calculates the power required to move a fluid through a system. It takes into account the flow rate, head pressure, fluid density (specific gravity), and pump efficiency.

2. How Does the Calculator Work?

The calculator uses the pump horsepower equation:

Where:

• \( Q \) — Flow rate in gallons per minute (GPM)
• \( H \) — Total head in feet
• \( SG \) — Specific gravity of the fluid (1 for water)
• \( \eta \) — Pump efficiency as a decimal (0.0 to 1.0)
• 3960 — Conversion factor to horsepower

Explanation: The equation calculates the power needed to move a given flow rate against a certain head pressure, adjusted for fluid density and pump efficiency.

3. Importance of Pump Horsepower Calculation

Details: Accurate horsepower calculation is crucial for selecting properly sized pumps, ensuring energy efficiency, and preventing motor overload or underutilization.

4. Using the Calculator

Tips: Enter flow rate in GPM, head in feet, specific gravity (1 for water), and pump efficiency as a decimal (e.g., 0.85 for 85%). All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is specific gravity?
A: Specific gravity is the ratio of the fluid's density to water's density. Water has SG=1. More dense fluids have SG>1.

Q2: What is typical pump efficiency?
A: Centrifugal pumps typically range from 40-85% efficiency, with higher efficiency in larger, well-designed pumps.

Q3: How do I measure total head?
A: Total head is the sum of static head (vertical distance) and friction head (pressure loss due to piping).

Q4: What's the difference between brake horsepower and water horsepower?
A: Water horsepower is the theoretical power needed, while brake horsepower includes pump inefficiencies (BHP = WHP/η).

Q5: Can I use this for viscous fluids?
A: This formula works best for water-like fluids. For viscous fluids, additional correction factors are needed.