Pipe Sizing Calculator (Velocity Method)
Minimum pipe diameter to carry a flow at your chosen design velocity, with the next standard size suggested.
Sizing at 2 m/s balances pipe cost against pumping energy for most water systems; suction lines size at ~1 m/s.
Formula
Pipe Sizing Calculator (Velocity Method) is a free pipe size calculator for pump engineers, plumbers and plant designers โ 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 Pipe Sizing Calculator (Velocity Method)
Minimum pipe diameter to carry a flow at your chosen design velocity, with the next standard size suggested. The calculation implements D = โ( 4Q / (ฯยทV) ) (ASHRAE Handbook โ pipe sizing; Crane TP-410). Sizing at 2 m/s balances pipe cost against pumping energy for most water systems; suction lines size at ~1 m/s.
How to use Pipe Sizing Calculator (Velocity Method)
- 1Enter Design flow in L/s.
- 2Enter Target velocity in m/s.
- 3Read Required inner ร instantly โ no submit button needed.
- 4Need US units? Flip the SI/Imperial toggle and every field converts.
Why use Pipe Sizing Calculator (Velocity Method)?
- โImplements the standard formula โ D = โ( 4Q / (ฯยทV) )
- โReference cited on-page: ASHRAE Handbook โ pipe sizing; Crane TP-410
- โOne-click SI โ Imperial toggle โ values convert in place, physics stays in SI
- โLive worked example: the substitution recomputes from your numbers
- โBuilt-in engineering verdict flags out-of-range results instantly
- โRuns entirely in your browser โ nothing uploaded, free forever
Frequently asked questions
What formula does the Pipe Sizing Calculator (Velocity Method) use?+
It computes D = โ( 4Q / (ฯยทV) ), per ASHRAE Handbook โ pipe sizing; Crane TP-410. The formula is displayed under the result along with a worked example substituted with your own inputs.
What should I keep in mind when using this calculator?+
Sizing at 2 m/s balances pipe cost against pumping energy for most water systems; suction lines size at ~1 m/s.
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 Pipe Sizing Calculator (Velocity Method) free to use?+
Yes โ 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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