Acceptance criteria: to be considered acceptable, manufactured parts must remain within which specified bounds that define the permissible variation from the nominal values?
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ABoundary limits
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BHole limits
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CSpecification
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DTolerances
Answer
Correct Answer: Tolerances
Explanation
Introduction / Context:Quality control relies on numeric windows around target values. These windows ensure parts function and assemble even with inevitable process variation.
Given Data / Assumptions:
- A drawing states nominal dimensions and allowable variation.
- Inspection compares measured values to the allowable window.
- We must identify the named bounds that measurements cannot exceed.
Concept / Approach:“Tolerances” define permitted deviation from nominal. As long as the actual size and geometry remain within the upper and lower tolerance limits (including any geometric tolerances), the part is acceptable.
Step-by-Step Solution:
Identify the acceptance window concept.Relate to standard drawing callouts (e.g., ±, limit dimensions, geometric frames).Conclude that parts must remain within tolerances.Verification / Alternative check:Inspection reports flag out-of-tolerance conditions; any value beyond stated tolerances triggers nonconformance.
Why Other Options Are Wrong:
- Boundary limits: ambiguous; could refer to derived boundaries (virtual condition), but acceptance is broadly governed by tolerances.
- Hole limits: applies only to a specific feature type, not all parts.
- Specification: too general; a specification contains tolerances but is not the numeric bound itself.
Common Pitfalls:Ignoring geometric tolerances; a size may be within limits but fail position or form tolerances, still rendering the part nonconforming.
Final Answer:Tolerances