1. What is Pump Sizing Calculation?

The pump sizing calculation determines the required horsepower for a pump based on flow rate, total head, fluid properties, and pump efficiency. Proper sizing ensures the pump can handle the required hydraulic load while operating efficiently.

2. How Does the Calculator Work?

The calculator uses the pump power equation:

Where:

• \( HP \) — Pump horsepower
• \( Q \) — Flow rate (gallons per minute, GPM)
• \( H \) — Total head (feet)
• \( SG \) — Specific gravity (water = 1.0)
• \( \eta \) — Pump efficiency (0.0 to 1.0)

Explanation: The equation calculates the theoretical power required to move a fluid at a given flow rate against a specific head, adjusted for fluid density and pump efficiency.

3. Importance of Pump Sizing

Details: Proper pump sizing is critical for energy efficiency, system reliability, and avoiding cavitation. Oversized pumps waste energy while undersized pumps can't meet system demands.

4. Using the Calculator

Tips: Enter flow rate in GPM, total head in feet, specific gravity (1.0 for water), and pump efficiency (typically 0.7-0.85 for centrifugal pumps). All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is total head?
A: Total head is the sum of static head, friction head, and pressure head that the pump must overcome.

Q2: How do I determine pump efficiency?
A: Efficiency depends on pump type and size. Centrifugal pumps typically range from 70-85% at best efficiency point (BEP).

Q3: What's the 3960 constant?
A: It's a conversion factor that accounts for units (1 HP = 550 ft-lb/sec) and water density (8.34 lb/gal).

Q4: Should I add a safety factor?
A: Yes, typically add 10-20% to the calculated HP to account for system uncertainties and future needs.

Q5: How does viscosity affect the calculation?
A: High viscosity fluids require special consideration as they affect both head and efficiency.