“The Missing Tip” and Optimum Handline Flow in 2 ½-inch Hose
The 1 3/16-inch tip is about attaining the largest possible flow at 50psi nozzle pressure while maintaining the true “handline” characteristics of deployability while flowing and advancing through a structure. It is about increasing the useable flow of the ADULTS handline by producing a vastly overwhelming “critical flow” stream to meet modern fuel load challenges such as high heat release rate “fire loads” encountered by the fire service today in commercial / large body fires.
The two common smooth bore tip sizes used on 2½-inch attack handlines are 11/8-inch and 1¼-inch. Their respective flows at 50psi nozzle pressure are 266gpm and 328gpm. The 1 3/16-inch smooth bore tip, provides a flow of essential 300 gpm at 50 psi.
We have discovered that most 2.5" being produced has an actual internal diameter of 2.75" or more. This means it is very likely that the friction loss per 100' is in the 13-15 range. With many departments already using 15 per 100 to flow for 265 GPM they could simply switch their tips and not even change their pump chart. The 1 3/16 matches up with the realities of currently manufactured hose and fire loads.
Please visit our library and read the articles "Hose Dreams" and "Nozzle Dreams". These outline specifically why the 1 3/16 tip is the "missing tip".
Several major nozzle manufacturers now produce and sell the 1 3/16 tip. It has been tested across the country by many departments. Please contact us for information on how you can integrate this valuable tool into your department.