K-Factor ↔ Equivalent Length Converter
Convert a fitting K-value into metres of straight pipe (and back) for quick sizing.
A 90° elbow (K≈0.9) in 100 mm pipe equals ~4.5 m of straight run. Equivalent length makes long fitting lists addable on the back of an envelope.
Formula
K-Factor ↔ Equivalent Length Converter is a free equivalent length 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 K-Factor ↔ Equivalent Length Converter
Convert a fitting K-value into metres of straight pipe (and back) for quick sizing. The calculation implements L_e = K·D/f (Crane TP-410 — L/D method). A 90° elbow (K≈0.9) in 100 mm pipe equals ~4.5 m of straight run. Equivalent length makes long fitting lists addable on the back of an envelope.
How to use K-Factor ↔ Equivalent Length Converter
- 1Enter Fitting K-factor.
- 2Enter Pipe inner diameter in mm.
- 3Enter Pipe friction factor f.
- 4Read Equivalent length, L_e/D ratio instantly — no submit button needed.
- 5Need US units? Flip the SI/Imperial toggle and every field converts.
Why use K-Factor ↔ Equivalent Length Converter?
- ✓Implements the standard formula — L_e = K·D/f
- ✓Reference cited on-page: Crane TP-410 — L/D method
- ✓One-click SI ⇄ Imperial toggle — values convert in place, physics stays in SI
- ✓Live worked example: the substitution recomputes from your numbers
- ✓Runs entirely in your browser — nothing uploaded, free forever
Frequently asked questions
What formula does the K-Factor ↔ Equivalent Length Converter use?+
It computes L_e = K·D/f, per Crane TP-410 — L/D method. 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?+
A 90° elbow (K≈0.9) in 100 mm pipe equals ~4.5 m of straight run. Equivalent length makes long fitting lists addable on the back of an envelope.
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 K-Factor ↔ Equivalent Length Converter 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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