Help with determining appropriate pipe size

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In summary, the conversation is discussing the necessary pipe size for connecting city water to a residential fire sprinkler system. The hydrostatic test results show a static pressure of 48 psi and a flow rate of at least 26 gpm is needed. The expert suggests that any black steel pipe can handle 50 psi and that the pressure needed at the end should be accounted for, taking into consideration the pressure drop due to pipe friction. They also mention that the friction loss calculation of 5.6 psi over 100 ft may not be accurate if it does not account for the elevation of the sprinklers.
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I'm trying to connect water from a city water supply to a residential fire sprinkler system. The pipe needs to be typical black steel, and hydrostatic test results show a static pressure of 48-psi. What size pipe would I need to achieve at least 26-gpm flow? I've calculated friction loss to be about 5.6-psi over a 100-ft length. Thanks in advance.
 
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How have you calculated friction loss without a pipe size?

26 gpm is pretty low, as is 48 psi. You won't need very big piping to accommodate that flow. Any black steel pipe can handle 50 psi with ease.

It's not what you can "acheive", it's the pressure you need at the end, accounting for pressure drop due to pipe friction. Almost literally any pipe size can accommodate a meager 26 gpm.

For instance, if you NEED 30 psi at the sprinklers, then you need a pipe size that will not reduce the head any lower than that.

Speaking of head, is that 5.6 psi (~13 ft static head) drop accounting for the elevation of the sprinkers?
 

1. What factors should be considered when determining the appropriate pipe size?

When determining the appropriate pipe size, it is important to consider the flow rate, pressure, and material of the fluid being transported. The length and layout of the pipeline, as well as the desired velocity and potential for future expansion, should also be taken into account.

2. How does the flow rate affect the pipe size?

The flow rate, or the volume of fluid passing through the pipe per unit of time, is a crucial factor in determining the appropriate pipe size. Higher flow rates require larger pipe sizes to prevent excessive pressure drops and maintain efficient flow.

3. What is the relationship between pressure and pipe size?

Pressure is directly related to the pipe size. As pressure increases, so does the required pipe size to ensure the pipeline can handle the pressure without bursting. Conversely, reducing the pipe size can increase the pressure, which may be desirable in certain systems.

4. How does the material of the fluid being transported impact pipe size?

The material of the fluid being transported can have a significant impact on the appropriate pipe size. Fluids with higher viscosities or those containing corrosive materials may require larger pipe sizes to prevent clogging or damage to the pipeline.

5. Are there any standard guidelines for determining pipe size?

There are various resources available, such as engineering handbooks and online calculators, that provide standard guidelines for determining pipe size based on flow rate, pressure, and other factors. However, it is important to also consider the specific needs and requirements of the system when determining the appropriate pipe size.

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