A screening surface is designated as blinded when___________________?
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Answer: C. Screen is plugged with solid particles
Explanation
Screen blinding occurs when solid particles completely plug the open screening apertures. Trapped particles prevent the passage of smaller fractions through the wire mesh screen. Option C accurately describes the physical phenomenon known as industrial screen blinding. Industrial screens classify particulate materials based primarily on physical particle size differences. Aperture size determines the maximum particle dimension that can pass through the mesh. Moisture and sticky fines often exacerbate mechanical blinding issues in screening equipment.
Blinding drastically reduces the effective screening area and lowers overall process throughput. Mining operations frequently install mechanical brush cleaners to prevent screen blinding problems. Maintaining clean screen surfaces ensures accurate particle size distribution in mineral processing. Oversize material in the undersize fraction typically indicates damaged or torn screen cloth. Undersize material retained in the oversize fraction points to inadequate screening time or overload. Abrupt capacity increases do not define blinding but rather reflect operational feed rate changes.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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