How do you read a fire hydrant flow test?
Conduct the test
- Record static pressure reading from gauge cap.
- Slowly open hydrant using the gate valve to purge air from the hydrant. When hydrant is full of water, open gate valve to desired flow-rate (usually full open).
- When the flow-rate stabilizes,
- Record nozzle pressure from the remote reader.
What is a pitot gauge used to calculate?
In theory, pitot gauges make it simple to measure the flow of fire hydrants and convert readings in pounds per square inch (PSI) to gallons per minute (GPM), enabling inspectors to quickly uncover reduced flow rates.
How do you use a pitot gauge for hydrant flow testing?
Flush the residual hydrant to remove any sediment and attach a nozzle cap with a gauge to the hydrant’s outlet. Slowly release the main valve until air is vented. Take a static pressure reading. Measure the inside diameter of the outlet nozzle or hydrant outlet where flow occurs.
How many gallons per minute will flow through a 1.5 inch pipe?
Metric PVC Pipe
| Assume Average Pressure. (20-100PSI) About 12f/s flow velocity | ||
|---|---|---|
| 1″ | 1.00-1.03″ | 37 gpm |
| 1.25″ | 1.25-1.36″ | 62 gpm |
| 1.5″ | 1.50-1.60″ | 81 gpm |
| 2″ | 1.95-2.05″ | 127 gpm |
How many GPM is a fire hose?
The 1 1/2-inch double jacket fire hose provides 5.06 gallons per minute per dry pound of hose (150 GPM / 29.6 lbs dry = 5.06 GPM/pound). While 150 GPM may be plenty in many situations, this hose trades ease of use for lower flow rates.
How much PSI is in a fire hydrant?
Fire hydrants are flow-tested at a residual pressure of 20 psi; therefore, firefighters should understand the typical flow rates of fire hydrants at that pressure.
What is the NFPA standard for fire hydrants?
NFPA 291 provides guidance on fire flow tests and marking of hydrants in order to determine and indicate the relative available fire service water supply from hydrants and to identify possible deficiencies which could be corrected to ensure adequate fire flows as needed.
How do you calculate psi from GPM and pipe diameter?
How do I calculate PSI from GPM and pipe diameter?
- Calculate the cross-sectional area of the pipe using the given diameter.
- Divide the flow rate measured in GPM by the area and take the square of the result.
- Multiply the value from step 2 with the density of water and divide by 2.
What do you need for a pitot gauge?
Your new hydrant flow test pitot gauge kit will arrive with a high-quality, extremely accurate pressure gauge connected to a nickel-plated pitot tube through a standard brass quick disconnect. Kit also includes PTFE tape and a convenient carrying case capable of holding two gauges at the same time.
Do you need a pitot gauge for a fire hydrant?
If your job requires a fire hydrant flow test, our pitot gauge kits will help you get the job done accurately and on-time. Your new hydrant flow test pitot gauge kit will arrive with a high-quality, extremely accurate pressure gauge connected to a nickel-plated pitot tube through a standard brass quick disconnect.
Can a psi gauge be converted to a GPM?
But in order to understand the results, the PSI readings need to be converted to GPM, the standard measurement of water flow. And that’s where it gets a little tricky. PSI can’t be directly converted to GPM; these are two different units of measure. PSI measures pressure and GPM measures flow rate.