Reciprocating screens inclined at 5 degrees utilize gyratory motion at the feed end and reciprocating action at discharge; they are unsuited for screening___________________?
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Answer: C. Heavy tonnages of rocks or gravel
Explanation
Reciprocating and shaking screens are designed for lighter materials and fine dry powders. They are unsuited for heavy tonnages of coarse rocks or gravel because high impact loads damage the mechanism. Heavy rock screening requires rugged vibrating grizzlies or heavy-duty inclined vibrating screens. Reciprocating screens combine gentle gyratory and reciprocating motions for precise powder classification. They typically operate on delicate materials where minimal particle degradation is desired. Heavy aggregate applications demand robust mechanical construction to withstand massive rock impacts.
Chemical plants use reciprocating screens for sizing light dry chemical powders and granules. Quarry operations avoid shaking screens for primary rock sizing due to severe structural wear. Matching screen types to material heaviness prevents catastrophic mechanical failures in service. Light metal powders down to 4 mesh size are successfully handled by specialized reciprocating sifters. Dry chemicals are routinely classified using gentle reciprocating and shaking screen mechanisms. Powdered food and granular materials benefit from the precision classification of reciprocating screens.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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