Hydraulic Calculations for Fire Sprinkler Systems
According to the National Fire Protection Association (NFPA), hydraulic calculations work best for designing fire sprinkler systems. The 2016 edition of the NFPA 13 handbook states, “A sprinkler system designed using hydraulic (calculation) is preferable over those systems designed using a pipe schedule approach.”
Fire protection systems such as a fire suppression system and fire sprinkler system can safeguard commercial buildings. If you are developing any sort of commercial building, make sure to contact a company like F2M Fire Drafting Designs Inc to get a fire sprinkler system design & layout.
Why are Hydraulic Calculations Important?
A reliable fire protection system is important for the safety of potential occupants and residents of a commercial or residential property.
Running hydraulic calculations ensures that the rate of flow in the pipes is sufficient for effectively controlling a fire situation. The National Fire Protection Association establishes and verifies the hydraulic calculations on the basis of three basic elements. These are:
- Available water supply
- Requirement of water delivery from the fire sprinkler system
- The piping network and issues like friction loss
Since a fire system is the first line of defense against fire, it is important to ensure that the pipes deliver enough water to extinguish the fire. This is only possible with the help of hydraulic calculations.
Water Flow Testing for Fire Protection System
You must conduct a test for water flow as part of the hydraulic calculation. Usually, the municipal water department makes this information public. However, you can also do this by measuring the flow and pressure at the particular water hydrant.
In certain cases, water from the municipal water supply is not enough to protect against fire hazards. To solve this issue, you can design the piping so that it can draw water from other open or closed sources.
Hydraulic Calculations for Fire Sprinkler Systems: Piping System
Configurations
There are three main types of piping networks for fire protection systems. This depends on the individual arrangement of pipes.
Tree
This type of pipe configuration resembles a tree’s trunk and branches. The main pipe branches into smaller pipes, which provide the individual sprinklers and other parts with water.
Loop
The grid configuration is quite similar to a ‘tree.’ However, the main pipe completes a loop at the surface as it extends and returns to the starting point.
Grid
In a grid configuration, there are rather two main pipelines running parallel to one another. Smaller segments of pipe connect the two lines together. With more routes leading to each sprinkler, there are fewer chances of friction losses.
Sprinkler Pressure Calculation
The function of a fire sprinkler involves converting pressure into kinetic energy. This makes the process of pressure calculation an incredibly complex one.
Depending on the pressure inside the pipe, the formula for calculating water flow through an outlet is:
Q (flow) = 29.83 x CD x d2 x √P
In this formula,
CD = discharge coefficient
d = diameter
p = pressure
The good news here is that fire sprinklers already have a design diameter. So, we can simplify the calculation by combining all factors except pressure into the ‘K-factor.’
So, the new formula will be:
Q = K x √P
To calculate the pressure when you already know the value of Q (flow), rearrange this formula as such:
P = (Q / K) 2
According to NFPA, your fire sprinkler should establish a minimum pressure of 7 psi. This is applicable even, especially if your calculations result in a smaller value. A minimum pressure of 7 psi ensures an appropriate spraying pattern.
Some exceptions for this include the following situations:
- Use of dry pipe sprinkler
- Use of quick-response sprinklers
- Combustible and concealed or non-sprinklered spaces
- Spaces divided into multiple compartments
- Units and corridors
Hydraulic Calculations for Fire Sprinkler Systems: Conclusion
F2M Fire & Drafting Designs Inc. is here to help with all your commercial and residential fire sprinkler system design needs. Whether you’re looking to install a new system or replace the old one, we can design a fire suppression system that fits well with your company’s specific requirements and budget.
Our many years of experience and expertise also provides the best hydraulic calculations with no errors whatsoever. Contact us today to schedule a meeting with our qualified experts to get all your answers and the best services in town.
Give us a call for an expert consultation.
F2M Fire & Drafting Designs Inc.
1231 Lafayette Ave, Fl 2
Bronx, New York, 10474
(718) 928-3009
info@f2mfadds.com
