1. What is a Pump Flow Rate GPM Calculator?

Definition: This calculator estimates the flow rate of a pump in gallons per minute (GPM) based on horsepower, pump efficiency, and head.

Purpose: It helps engineers and technicians determine the expected flow rate of pumps in various hydraulic systems.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( Q \) — Flow rate (gallons per minute)
• \( HP \) — Horsepower of the pump
• \( \eta \) — Pump efficiency (0-1)
• \( H \) — Total dynamic head (feet)

Explanation: The formula converts mechanical power to hydraulic power, accounting for pump efficiency and the work needed to overcome head pressure.

3. Importance of Pump Flow Rate Calculation

Details: Accurate flow rate estimation ensures proper pump selection, system design, and energy efficiency in fluid transport systems.

4. Using the Calculator

Tips: Enter the pump horsepower, efficiency (default 0.85), and total head in feet. All values must be > 0, with efficiency between 0 and 1.

5. Frequently Asked Questions (FAQ)

Q1: What is the constant 3960 in the formula?
A: This is the conversion factor between horsepower and foot-pounds per minute (1 HP = 3960 ft-lb/min).

Q2: What's a typical pump efficiency value?
A: Most pumps have efficiencies between 0.7-0.9 (70-90%), with 0.85 being a common default value.

Q3: How do I determine total dynamic head?
A: Total head includes static head, friction losses, and pressure differences in the system.

Q4: Does this work for all fluid types?
A: The formula is for water. For other fluids, you'll need to adjust for specific gravity.

Q5: How accurate is this calculation?
A: It provides theoretical maximum flow. Actual flow may be lower due to system losses and pump curves.