What is the Total Pressure Loss (TPL) for a hose assembly with 400 feet of 5-inch hose wyed into two 2 1/2-inch hoses flowing at 200 gpm each?

• A. 35 psi
• B. 39 psi
• C. 45 psi
• D. 50 psi

Answer: (B)

To determine the Total Pressure Loss (TPL) for the described hose assembly, it is important to consider both the friction loss in the hoses and any additional losses due to fittings and connections.

In this scenario, you have a 400-foot length of 5-inch hose that branches off into two 2-1/2-inch hoses, each flowing at 200 gallons per minute (gpm). The flow rate in the larger hose (the 5-inch) will be the sum of the flows through both smaller hoses; therefore, the total flow through the 5-inch hose is 400 gpm (200 gpm per 2-1/2-inch hose).

To calculate the friction loss, you can reference a friction loss chart or use a calculation method specific to the hose diameter, length, and flow rate. For a 5-inch hose, the friction loss is significantly lower than that for smaller hoses due to its larger diameter. Using standard formulas or tables, one can note that the friction loss for 400 feet of 5-inch hose at 400 gpm typically results in a loss around 6 psi per 100 feet, leading to about 24 psi for the 400 feet.

Next, consider the additional friction losses associated