What is a Multi-purpose handline nozzle? Why would you want to use a Multi-purpose nozzle? What flexibility and benefits does it offer? What do you need to know about training with a Multi-purpose nozzle? We will explore in depth the latest, simplified design of the Multi-purpose nozzle.
Multi-purpose Nozzle Defined
A multipurpose nozzle is a combination smooth bore and fog nozzle. It provides the maximum reach and penetration of a smooth bore, while still enabling the benefits of a fog stream at the same time or independently. This versatile type nozzle has the ability for large flows at reduced pressures, and is well suited for multiple applications: interior, exterior, and high-rise attacks, CAFS systems, foam applications, direct and indirect attacks, cooling, protection, and ventilation.
In the market today there are a couple types of multi-purpose nozzles. One style (example: patented Akron Brass Saberjet) is designed and operated differently than the standard fog nozzle. The shutoff handle not only controls the water flow from the open/close perspective but also controls the smooth bore. The bumper is used to control the spray pattern and to access the fog flow. The nozzle also allows the operator to flow both smooth bore and fog at the same time or independently. This nozzle is dual flow and dual pressure, meaning the smooth bore and fog flows, and pressures are different. The smooth bore is operated at 50 psi and the fog flow at 75 psi.
Another style of multi-purpose nozzle is one in which the fog or additional smooth bore tip is attached to the end of an integrated smooth bore. The additional tip is flipped up and locked to the integrated tip. The additional tips specified may or may not be the same flow and pressure, so operation from the pump and nozzle operator perspective is similar to that of a break-apart nozzle, much depends on the extra tip chosen.
The latest multi-purpose nozzle (example: patent pending Akron Brass UltraJet). This nozzle has the ability to flow a smooth bore and fog independently, and operates just like a typical fixed orifice fog nozzle. The shutoff handle controls the open/close water flow to the nozzle and the bumper regulates the pattern; smooth bore, narrow fog, wide fog and flush. Flows match in both smooth bore and fog, making it easy on the pump operator and the nozzle person. So operating at a low pressure such as 50 psi (3.5 bar) flow is consistent throughout the spray patterns.
The Latest in Multi-Purpose Nozzle Design – Flexibility, Benefits and Training
If the fire department uses both smooth bore and fog nozzles, the multi-purpose should be considered. With the ability to turn the bumper to change flow pattern, there is not the need for multiple types of nozzles on truck. The multi-purpose provides the smooth bore, narrow fog, and wide fog all-in-one. Outfitting trucks with the same nozzle style and type, where possible, reduces the complexity in training and provides consistency for both the pump and nozzle operator.
The ability to flow both water and foam is another benefit to the multi-purpose nozzle. The smooth bore provides long reach and reduces the breakdown of the bubble structure, helping to maximize the advantage of using foam. Having the ability to flow both water and foam well with the same nozzle, give those departments a distinct advantage when it comes to simplifying operations.
Fire departments have the ability to operate the nozzle at lower pressure and get the same water flow in all patterns. Just because the pattern is changing this does not mean the gallons per minute has changed. For example, if a nozzle is specified with a 1” tip, the smooth bore flow at 50 psi is 210 gallons per minute, and so is the fog flow. Same smooth bore flow, same fog flow. This makes the amount of water being put on the fire consistent in all spray patterns, eliminating extra training on changing water flows.
The ability to operate the multi-purpose nozzle at lower pressures can help to reduce reaction force for the nozzle operator. For example, if a typical fog nozzle is rated 150 gpm @100 psi, the reaction force is 76 pounds. A multi-purpose nozzle with a 7/8” smooth bore tip that flows 161 gpm @ 50 psi, has a reaction force of 60 pounds. Not only does the nozzle in smooth bore and fog flow more, but the reaction force has decreased 20%.
Training with the newest multi-purpose nozzle is simplified. It is designed to flow one spray pattern at time by turning the bumper. This is in keeping with the standard fog nozzle. The nozzle is essentially a fixed orifice or single gallonage. It is specified by the smooth bore tips size which dictates the flow. The nozzle is generally operated at a smooth bore pressure of 50 psi. If more flow is required, the pressure is increased, if less flow is required the pressure is decreased, keeping the operations at the pump and the nozzle as easy as possible. One