1. What is Pump Discharge Pressure?

Pump Discharge Pressure (PDP) is the total pressure required at the pump outlet to overcome nozzle pressure, friction loss in hoses, and elevation loss/gain. It's a critical parameter in firefighting and fluid transfer operations.

2. How Does the Calculator Work?

The calculator uses the PDP equation:

Where:

• \( NP \) — Nozzle Pressure (psi)
• \( FL \) — Friction Loss (psi)
• \( EL \) — Elevation Loss (psi)

Explanation: The equation sums up all pressure components to determine the total pressure required at the pump discharge.

3. Importance of PDP Calculation

Details: Accurate PDP calculation ensures proper pump operation, adequate water flow, and effective fire suppression. It helps prevent pump overload and ensures equipment safety.

4. Using the Calculator

Tips: Enter nozzle pressure, friction loss, and elevation loss in psi. All values must be non-negative numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is typical nozzle pressure for firefighting?
A: Standard nozzle pressure is typically 100 psi for smooth bore nozzles and 75-100 psi for fog nozzles.

Q2: How is friction loss calculated?
A: Friction loss depends on hose diameter, length, flow rate, and hose material. It's typically calculated using specific formulas or tables.

Q3: What about elevation gain?
A: Elevation loss is positive when pumping uphill. For downhill pumping, it would be negative (pressure gain).

Q4: Are there safety factors to consider?
A: Yes, most departments add a safety margin of 10-25 psi to account for unexpected pressure variations.

Q5: Can this calculator be used for other fluids?
A: While the principle is similar, specific calculations may vary for different fluids due to varying viscosity and density.