Snag grinding in foundry/forge finishing: Which operations qualify as typical examples?
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ATrimming the surfaces left by sprues and risers on castings
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BGrinding the parting line left on castings
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CRemoving flash on forgings
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Dall of these
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Enone of these
Answer
Correct Answer: all of these
Explanation
Introduction / Context:Snag grinding is a rough, off-hand grinding process used in foundries and forges to remove excess metal quickly: risers, sprues, parting lines, and flash. It improves handling safety and prepares parts for subsequent machining or inspection.
Given Data / Assumptions:
- Portable grinders or swing-frame machines with coarse, hard wheels.
- Cast or forged components with gate/flash remnants.
- Emphasis on stock removal, not precision finish.
Concept / Approach:All listed operations target removal of casting/forging extras. The wheel is selected for aggressive cutting and durability under intermittent contact and variable geometry.
Step-by-Step Solution:
Identify typical post-casting excess: sprues/risers, parting lines.Identify forging excess: flash at die parting.Recognize all are removed by snag grinding → choose “all of these”.Verification / Alternative check:Foundry process plans list snagging as an early finishing step prior to shot blasting and machining.
Why Other Options Are Wrong:Each single option is correct, therefore the comprehensive answer is “all of these.” “None” is invalid.
Common Pitfalls:Expecting fine tolerances from snagging; it is a coarse, high-removal operation and may leave significant surface roughness.
Final Answer:all of these