Air Gauge Selector
This selector turns basic bore and tolerance inputs into a preliminary air-gauging configuration. Final jet size, clearance, master sizes, pneumatic response and fixture design require drawing review.
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Ready for your data
Complete the inputs or load the worked example. Results will include the primary decision, interpretation and supporting metrics.
Worked example
For a 20 mm bore with 20 µm total tolerance, two channels and static measurement, the tool recommends a two-channel touchscreen starting point with an engineered air plug and matched setting master.
Load the example in the calculatorFormula and methodology
- The selector classifies tolerance sensitivity and maps channel count to an instrument class.
- Dynamic applications are flagged for response-time and measurement-strategy review.
- Very small, large or tight-tolerance features are explicitly escalated for engineering review.
Tolerance span = upper size limit − lower size limitRecommended resolution is application dependent and must be materially finer than the decision interval. How to interpret the result
- The result is a configuration starting point, not a final gauge design.
- Surface finish, ports, grooves, ovality, taper, material and available land length can change suitability.
- Air supply quality and master traceability are part of the measurement system.
Common errors and limitations
- Selecting only from nominal diameter.
- Ignoring jet location, surface interruptions and master requirements.
- Treating instrument display resolution as total measurement uncertainty.
Turn the calculation into an engineering decision
Share the drawing, process conditions and result context. AccuTouch can review the measurement, fixture, SPC or automation starting point.
Frequently asked questions
What information is needed for final air plug selection?
Provide the component drawing, limits, surface condition, depth, cycle time, datum scheme and handling method.
Can an air plug measure ovality?
It can support configured comparative measurements, but jet arrangement and rotation or multiple circuits must be engineered for the feature.
Why is a setting master required?
Comparative air gauging needs traceable masters to establish the pneumatic measurement scale and working point.
Technical references
Use the current controlled standard or your organisation’s approved method where it differs from this screening tool.
Method content reviewed 13 August 2026. Independent technical approval is still required before production publication or use in a controlled quality procedure.