What is the total pressure loss for a hose assembly with two 300-foot sections of 3-inch hoses siamesed into a 200-foot 5-inch attack line flowing at 350 gpm?

• A. 32 psi
• B. 36 psi
• C. 40 psi
• D. 44 psi

Answer: (D)

To determine the total pressure loss in the described hose assembly, it's essential to consider both the friction loss in each section of the hose and any additional factors.

In this scenario, we have two sections of 300-foot 3-inch hoses siamesed into a single 200-foot 5-inch attack line. When calculating pressure loss, it's important to take into account the specific flow rates and the respective friction loss for the different hose sizes.

1. Friction Loss Calculation: The pressure loss is primarily calculated using the formula for determining friction loss in hoses, which is typically based on the formula:

• FL = C × (Q^2) × (L/H), where FL is the friction loss in psi, C is the friction loss coefficient, Q is the flow rate in gallons per minute, L is the length of the hose in feet, and H is the hose diameter in inches.

2. 3-inch Hose Sections: For the 300-foot sections of 3-inch hose, the friction loss would be calculated using the appropriate coefficient for the 3-inch hose at 350 gpm. For a 3-inch hose, the friction loss can tend to be higher due to the smaller diameter compared to the attack