1. What is the Centrifugal Pump Horsepower Formula?

The centrifugal pump horsepower formula calculates the power required to move fluid through a pump system. It accounts for flow rate, head pressure, fluid density, 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 (water = 1.0)
• \( \eta \) — Pump efficiency (0-1, typically 0.7-0.9)
• 3960 — Conversion factor to horsepower

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

3. Importance of Pump Power Calculation

Details: Proper horsepower calculation ensures correct pump sizing, prevents motor overload, and optimizes energy efficiency in fluid systems.

4. Using the Calculator

Tips: Enter flow rate in GPM, head in feet, specific gravity (1.0 for water), and pump efficiency (typically 0.7-0.9). All values must be positive.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between brake horsepower and water horsepower?
A: Water horsepower is the theoretical power to move the fluid. Brake horsepower (calculated here) includes pump inefficiencies.

Q2: How does specific gravity affect horsepower?
A: Higher SG fluids (more dense) require more power to pump at the same flow and head conditions.

Q3: What's a typical pump efficiency value?
A: Centrifugal pumps typically range from 70-90% efficiency (0.7-0.9), depending on size and design.

Q4: Why is the conversion factor 3960?
A: It combines unit conversions: 1 HP = 550 ft-lb/sec, 1 gallon water = 8.34 lb, 1 minute = 60 sec.

Q5: How do I account for system losses?
A: Include all losses in your total head calculation (pipe friction, elevation, fittings, etc.).