sweetliver
Mechanical
- Feb 26, 2025
- 8
Hi All,
We are going to replace an existing pump with one of a higher capacity (maximum expected operating flowrate is 340 GPM). The suction line size is 6 inch, while the discharge line size is 4". These corresponds to liquid velocities of 3.8 ft/s for suction, and 8.6 ft/s for discharge. However, the pump we are planning to select has flanges of 3" in the suction (6" x 3" reduction nozzle) and 2" in the discharge (4" x 2" increase nozzle). According to the calculated liquid velocities in these reduced sections, the suction nozzle will have a velocity of 14.7 ft/s, while the discharge nozzle will have a velocity speed of 32.4 ft/s.
My role of thumb is to not to exceed 8 ft/s in the suction and not to exceed 15 ft/s in the discharge.
Does the liquid velocity in the nozzle matter, and should I only stick to the size and the liquid velocities of the main lines?
Thank you in advance.
We are going to replace an existing pump with one of a higher capacity (maximum expected operating flowrate is 340 GPM). The suction line size is 6 inch, while the discharge line size is 4". These corresponds to liquid velocities of 3.8 ft/s for suction, and 8.6 ft/s for discharge. However, the pump we are planning to select has flanges of 3" in the suction (6" x 3" reduction nozzle) and 2" in the discharge (4" x 2" increase nozzle). According to the calculated liquid velocities in these reduced sections, the suction nozzle will have a velocity of 14.7 ft/s, while the discharge nozzle will have a velocity speed of 32.4 ft/s.
My role of thumb is to not to exceed 8 ft/s in the suction and not to exceed 15 ft/s in the discharge.
Does the liquid velocity in the nozzle matter, and should I only stick to the size and the liquid velocities of the main lines?
Thank you in advance.
