When this Kv estimate is appropriate
The factory schema uses the classic turbulent relation between Q, ΔP, and SG. Manufacturer digitized curves supersede this estimate for final valve selection.
Model assumptions
- Incompressible fluid with constant SG; not for flashing, choked gas, or multiphase mixtures.
- ΔP must be positive and Q in SI base as wired in the schema; adjust carefully when copying field data.
- Pipe reducers upstream/downstream of the valve are not auto-modeled.
- Result is a screening coefficient, not a guarantee of catalog trim availability.
References & further reading
- IEC 60534 / ISA sizing practices for control valves — conceptual background.
- Vendor-specific Kv/Cv bulletins for final trim and noise predictions.
Shareable URL
When the toolbar exposes “Copy shareable link”, inputs can be encoded in the URL so colleagues can reopen the same case. All computations run locally in your browser; this tool may not expose share links yet.
Frequently asked questions
- Why is Kv dimensionless here but vendors cite m³/h?
- Display units follow the grid; underlying SI base is consistent with the formula note in Tools.Calculators.
- Can I size a safety valve with this?
- No. Relief devices require code-specific procedures.
- Is data uploaded?
- No. The dynamic calculator runs locally.
Extended copy on this page (headings, assumptions, references, FAQs) may be drafted or localized with AI assistance; engineering judgment and governing codes still apply. Numerical models run locally in your browser as implemented. For contract-critical work, cite primary standards and qualified review.