Anonymous
Anonymous asked in Science & MathematicsEngineering · 7 years ago

# k factor for hydrant?

What is the definition for the k factor for a hydrant or what does the k factor represents?

Q=k*sqrt(p)

thanks!

Relevance
• 7 years ago

Architects and engineers consider the K-factor of a sprinkler head when designing a fire sprinkler

system. The system uses many variables to determine the amount of water that will flow through

the sprinkler head. By utilizing the K-factor, the builders can confirm that enough water will flow from

the sprinkler to extinguish any possible fire.

The K-factor is the number of liters of water that flows through the sprinkler for each bar of water

pressure. A bar is the standard air pressure at sea level. It is measured with specialized equipment.

This is a vital statistic when calculating the capacity of a sprinkler system. The K-factor is often stated in a manufacturer’s information furnished with sprinkler heads.

In fire protection engineering, the K-factor formula is used to calculate the discharge rate from a

nozzle. Nozzles can be fire sprinklers or water mist nozzles, hose reel nozzles, water monitors and

deluge fire system nozzles.

The flow rate of a nozzle is given by q =k*sqrt(p) as u had written , where q is the flow rate in litres

per minute (LPM), p is the pressure at the nozzle in Bar and K is the K-factor is given in units of

LPM/SQRT(Bar).

• Anonymous
7 years ago

There is no standard k factor for the flow from hydrants. The desigh of the hydrant affects the flow rate. The construction of the hydrant but is a key factor, particularly the entrance rom the barrel to the butt. There are three different constructions. one has a rounded entrance, another entrance is square, and the last extends into the barrel. Flow is determined from charts showing theoretical flow (by butt size) and pitot pressures determined during flow. These estimates are modified by coefficients determined by the type of butt construction.

• 7 years ago

it seem to be CV factor. it is coefficient of flow and characterizes ability of valve (or hydrant in this case) to handle flow.

Q = quantity of vluid (volume)

p = pressure

k = CV factor relative or more precisely k=CV/sqrt(G)

http://www.hisaka.co.jp/english/valve/techDoc/tech...

• 7 years ago

L= Discharge 0.785 3.14

D= dia of the outlet

P=pressure

L=2/3 x D xD x root p

D D root P LPM per pont

mm mm kg/cm LPM

Hydrant point 0.667 20 20 2.366431913 631.3640345 631.3640345

k factor 266.8 266.8