1. What is Pump Horsepower?

Pump horsepower (HP) is the power required to move a fluid at a specified flow rate against a given head height, accounting for the fluid's specific gravity and the pump's efficiency.

2. How Does the Calculator Work?

The calculator uses the pump horsepower formula:

Where:

• \( Q \) — Flow rate in gallons per minute (GPM)
• \( H \) — Total head height in feet
• \( SG \) — Specific gravity of the fluid (dimensionless)
• \( \eta \) — Pump efficiency (decimal, 0-1)
• 3960 — Conversion factor (foot-pounds per minute to horsepower)

Explanation: The formula calculates the theoretical power required to move the fluid, then divides by pump efficiency to get actual required horsepower.

3. Importance of Pump Horsepower Calculation

Details: Proper horsepower calculation ensures correct pump selection, prevents underpowered or oversized pumps, and helps optimize energy efficiency.

4. Using the Calculator

Tips: Enter flow rate in GPM, head height in feet, specific gravity (1.0 for water), and pump efficiency (typically 0.7-0.9 for centrifugal pumps).

5. Frequently Asked Questions (FAQ)

Q1: What is specific gravity?
A: The ratio of the fluid's density to water's density (1.0). For water at 4°C, SG=1.0.

Q2: How do I estimate pump efficiency?
A: Centrifugal pumps typically have 70-90% efficiency. Check manufacturer specifications for exact values.

Q3: What is total dynamic head?
A: The sum of static head (vertical distance) and friction head (pressure loss due to pipe friction).

Q4: Can I use this for viscous fluids?
A: This formula works best for water-like fluids. For viscous fluids, additional corrections are needed.

Q5: What's the difference between brake HP and water HP?
A: Water HP is theoretical power needed to move the fluid. Brake HP is actual power required by the pump (including inefficiencies).