Metrology terminology in manufacturing: which term refers specifically to the measured size of the finished, produced part as verified by inspection instruments?
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AActual size
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BDimensioned size
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CProduction size
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DBasic size
Answer
Correct Answer: Actual size
Explanation
Introduction / Context:Drawings specify target dimensions and permissible variation. During inspection, the measured value obtained from calipers, micrometers, or CMM equipment is compared to the specification to determine acceptability.
Given Data / Assumptions:
- There exists a nominal (called out) dimension with tolerances.
- A finished part has been manufactured and measured.
- We seek the correct term for the measured value.
Concept / Approach:Terminology matters. The “actual size” is the measured dimension of the produced feature. “Basic size” is a theoretically exact size used as a starting point for limits and fits. “Dimensioned size” is the value shown on the drawing. “Production size” is imprecise jargon.
Step-by-Step Solution:
Identify the context: inspection of a finished item.Match the definition: measured value → actual size.Confirm difference from theoretical or nominal terms.Verification / Alternative check:Inspection reports list measured values under “actual” readings; conformance is determined by checking whether these lie within stated limits.
Why Other Options Are Wrong:
- Dimensioned size: the nominal value printed on the drawing, not a measurement.
- Production size: nonstandard term.
- Basic size: theoretical exact size used for establishing limits, not a measured result.
Common Pitfalls:Confusing “actual” with “maximum material condition” or “virtual condition”; those are feature states or boundaries, not measurements.
Final Answer:Actual size