Sonic conductance

ISO 6358 Sonic Conductance Air Flow Calculator

Estimate standard air flow from ISO 6358 sonic conductance C, critical pressure ratio b, and upstream and downstream pressures. Enter the application values to calculate four decision-ready outputs and review the governing assumptions before selecting equipment.

Use calculator All tools

Sonic conductance

Run the calculation

Engineering visual

ISO 6358 Flow Calculator calculation path

Upstream pressure drives flow through the valve restriction to downstream pressure. The restriction and pressure drop are shown at the component where they occur.

01Sonic conductance C
02Calculate and compare
03Standard flow

Standard flow

Standard flow in SCFM

Absolute pressure ratio

Subcritical flow factor

Calculation reference

What this tool checks.

Use the displayed relationship to understand how the entered conditions affect the result. Treat the output as a preliminary selection, then verify actual operating conditions, catalog limits, and safety margin.

Inputs

Sonic conductance C
Critical pressure ratio b
Upstream gauge pressure
Downstream gauge pressure

Outputs

Standard flow
Standard flow in SCFM
Absolute pressure ratio
Subcritical flow factor

Engineering guide

Use the result with the right context.

Calculate iso 6358 flow calculator for a pneumatic application and compare the result with supplier data.

Calculation workflow

Enter Sonic conductance C, Critical pressure ratio b, Upstream gauge pressure and replace every default with application data.
Run the calculation while keeping pressure, temperature, geometry, and reference states consistent.
Interpret Standard flow, Standard flow in SCFM, Absolute pressure ratio against the supplier datasheet, machine risk, and an appropriate design margin.

Assumptions and limits

Air is treated as an ideal gas and the entered coefficient or geometry must match the supplier's stated reference conditions.
Confirm the entire flow path, including tubing, fittings, manifolds, silencers, and simultaneous valve demand.

How to use the ISO 6358 Flow Calculator

Start with measured or supplier-confirmed values for Sonic conductance C, Critical pressure ratio b, Upstream gauge pressure, Downstream gauge pressure. The calculator updates all outputs together, making it easier to see which assumption controls the preliminary selection.

What the result means

Standard flow, Standard flow in SCFM, Absolute pressure ratio, Subcritical flow factor answer different parts of the same engineering question. Use the primary result for selection, the secondary values to audit units and margins, and the visible formula to reproduce the calculation in an RFQ worksheet.

Engineering limits

Air is treated as an ideal gas and the entered coefficient or geometry must match the supplier's stated reference conditions. Confirm the entire flow path, including tubing, fittings, manifolds, silencers, and simultaneous valve demand. Final approval requires the current manufacturer datasheet and validation under installed conditions.

FAQ

Common review questions.

01Tool noteWhat does the ISO 6358 Flow Calculator calculate?

Estimate standard air flow from ISO 6358 sonic conductance C, critical pressure ratio b, and upstream and downstream pressures. It returns Standard flow, Standard flow in SCFM, Absolute pressure ratio, Subcritical flow factor so the primary answer and its supporting checks stay together.

02Tool noteCan I use the result as a final component selection?

Use it for preliminary engineering and RFQ comparison. Final selection must include supplier ratings, installation losses, transient conditions, applicable standards, machine risk, and validation testing.

03Tool noteWhy can a supplier calculation differ?

Supplier tools may use proprietary test curves, correction factors, rounding, leakage allowances, or reference conditions. Match those conditions and replace the defaults before comparing results.

04Tool noteWhat should I verify after using the ISO 6358 Flow Calculator?

Check the entered units and reference conditions, then compare the calculated outputs with manufacturer ratings, application safety margins, transient loads, installation losses, and measured machine performance.