How to determine the diameter of fire hoses?
Thread Content
As the title suggests, how should the diameter of indoor and outdoor fire hoses be determined in design?
In the Design Fire Protection Code for petrochemical enterprises (2008 edition), the maximum flow velocity for fire protection pipelines is limited to 3.5 m/s； The limit in older versions was 5 m/s. According to the building design fire protection codes, the maximum flow rate for fire protection pipes is 2.5 m/s ； In the fire protection codes for coal chemical plant design that have not yet been issued, the maximum flow velocity limit is also 3.5 m/s ； So, it depends on what type your fire hose is, and the relevant standards will apply. According to the fire protection codes for architectural design, fire service risers are also required to have a diameter of not less than DN100 ； The branch pipe must not be smaller than DN65, otherwise the flow rate requirements will not be met. For the outdoor fire protection piping systems in chemical plant areas, it is recommended that the diameter be no smaller than DN300. The specific value can be determined by the owner based on the designed water flow rate!
Of course, it should also be noted that the head loss for fire protection is calculated based on the most unfavorable condition. The pressure requirement under the most adverse conditions must also meet the design specifications. If the original poster is not sure, they can provide more details so that everyone can discuss it.
For detailed calculations, refer to the fire protection design codes for petrochemical enterprises; however, it is best to contact the local authorities with relevant qualifications to facilitate the fire safety inspection
It’s the same; it depends on the water volume, mainly the issue of determining the amount of water needed for firefighting.
After determining the flow rate in each section of the fire protection piping network, the diameter of each section can be calculated using the formula Q=¼ΠD2*V. Typically, the diameter and the value of the head loss per unit length i can be found directly from hydraulic calculation tables, based on Q and the flow rate V