What type of nozzles are called automatic nozzles?

Automatic nozzles are designed to maintain a constant pressure regardless of the changes in the flow rate. This is achieved through a mechanism that adjusts the nozzle opening based on the pressure of the water being supplied. As a result, these nozzles can ensure a stable and effective spray pattern which is critical in fire suppression scenarios.

By keeping a constant pressure, automatic nozzles provide firefighters with the ability to consistently deliver water at the optimal nozzle reaction and reach, enhancing their ability to combat fires effectively.

In contrast, variable flow nozzles would allow the operator to adjust the flow, which does not align with the concept of maintaining constant pressure. Fixed flow nozzles, on the other hand, are designed to operate at a specific flow rate and pressure without the capability to adjust. High-pressure nozzles focus on delivering water at a higher pressure which is not synonymous with the automatic function of maintaining consistent pressure across varying flows.