NPSHa Calculator — Flooded Suction
NPSH available with the supply tank above the pump (flooded suction).
Flooded suction is the easiest cavitation insurance there is. Watch hot liquids: at 90 °C, vapour pressure alone steals ~7 m of NPSHa.
Formula
NPSHa Calculator — Flooded Suction is a free flooded suction npsh for pump engineers, plumbers and plant designers — instant, accurate and 100% client-side, with the governing formula and reference shown next to the result so the number can be defended, not just quoted.
About NPSHa Calculator — Flooded Suction
NPSH available with the supply tank above the pump (flooded suction). The calculation implements NPSHa = (P_atm + P_tank − P_v)/ρg + H_submergence − h_f (ANSI/HI 9.6.1). Flooded suction is the easiest cavitation insurance there is. Watch hot liquids: at 90 °C, vapour pressure alone steals ~7 m of NPSHa.
How to use NPSHa Calculator — Flooded Suction
- 1Enter Liquid level above pump eye in m.
- 2Enter Suction line friction in m.
- 3Enter Liquid temperature in °C.
- 4Enter Tank surface pressure (gauge) in kPa(g) (0 for open tanks; negative for vacuum vessels).
- 5Read NPSH available instantly — no submit button needed.
- 6Need US units? Flip the SI/Imperial toggle and every field converts.
Why use NPSHa Calculator — Flooded Suction?
- ✓Implements the standard formula — NPSHa = (P_atm + P_tank − P_v)/ρg + H_submergence − h_f
- ✓Reference cited on-page: ANSI/HI 9.6.1
- ✓One-click SI ⇄ Imperial toggle — values convert in place, physics stays in SI
- ✓Runs entirely in your browser — nothing uploaded, free forever
Frequently asked questions
What formula does the NPSHa Calculator — Flooded Suction use?+
It computes NPSHa = (P_atm + P_tank − P_v)/ρg + H_submergence − h_f, per ANSI/HI 9.6.1. The formula is displayed under the result.
What should I keep in mind when using this calculator?+
Flooded suction is the easiest cavitation insurance there is. Watch hot liquids: at 90 °C, vapour pressure alone steals ~7 m of NPSHa.
Can I use this for pump selection?+
Use it to establish the duty (flow, head, NPSH, power) and then pick a pump whose curve passes through that point near best efficiency. The tool gives you the engineering numbers a supplier will ask for.
Is the NPSHa Calculator — Flooded Suction free to use?+
Yes — completely free, no sign-up, no limits. It runs client-side in your browser, so inputs stay private and results are instant even on slow connections.
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