Valve Design Nozzleman Flow Control... Why is it important in fire ground operations? Nozzleman Flow Control... Why is it important in fire ground operations?

Nozzleman Flow Control Benefits...  Ability for nozzle operator to change flow on demand  Nozzle has ability to adjust to new flow setting by itself  Is simple and easy... like a car’s gas pedal  Does not affect stream reach (other than flow change)  Does not affect stream quality  Ability for nozzle operator to change flow on demand  Nozzle has ability to adjust to new flow setting by itself  Is simple and easy... like a car’s gas pedal  Does not affect stream reach (other than flow change)  Does not affect stream quality

What Flow Control is NOT!  Changing the nozzle opening manually This requires change in pump pressure  Calling pump operator to change pressure ?? psi  Gating a ball valve to reduce flow  Anything that does not react instantly to provide a change in the flow  Changing the nozzle opening manually This requires change in pump pressure  Calling pump operator to change pressure ?? psi  Gating a ball valve to reduce flow  Anything that does not react instantly to provide a change in the flow

Difference in Valve Designs Ball Valve Design Slide Valve Design

Ball Valve Design (Valve gated half way)

Primary Advantages of Ball Valve...  Simple and familiar design  Easily serviced by repair people with commonly available parts  Can be used in break-apart nozzle configurations  Simple and familiar design  Easily serviced by repair people with commonly available parts  Can be used in break-apart nozzle configurations

Disadvantages of Ball Valve...  Designed to be used fully opened or closed  Creates turbulence when partially open  Seats require regular replacement  Difficult to open under pressure  Valve seal area in normal direct water path  Can bind and tighten with age  Designed to be used fully opened or closed  Creates turbulence when partially open  Seats require regular replacement  Difficult to open under pressure  Valve seal area in normal direct water path  Can bind and tighten with age

Slide Valve Design (Valve gated half way)

Primary Advantages of a Slide Valve...  Does NOT create turbulence when “throttled”  Is smoother and easier to open under pressure  Requires little to no maintenance  No seats to replace  Has greater durability  Valve seal area not in direct water path  Does not bind or tighten with age  Does NOT create turbulence when “throttled”  Is smoother and easier to open under pressure  Requires little to no maintenance  No seats to replace  Has greater durability  Valve seal area not in direct water path  Does not bind or tighten with age

Disadvantages of a Slide Valve...  Moves more easily than a ball valve which increases possibility of accidental movement of valve (without detents)  Is not commonly familiar to field repair personnel  Design does not work well with break-apart nozzle and valve combinations  Can be more expensive than a ball valve  Moves more easily than a ball valve which increases possibility of accidental movement of valve (without detents)  Is not commonly familiar to field repair personnel  Design does not work well with break-apart nozzle and valve combinations  Can be more expensive than a ball valve