Actual operating speed of a ball mill may vary from 65 to 80% of the critical speed. Which of the following duties would require the ball mill to be operated at maximum percentage of critical speed ?

Wet grinding in low viscous suspension.

Wet grinding in high viscous suspension.

Dry grinding of large particles (upto 1.25 cms).

Dry grindng of large particles in un-baffed mills.

Actual operating speed of a ball mill may vary from 65 to 80% of the c

1.	Actual operating speed of a ball mill may vary from 65 to 80% of the critical speed. Which of the following duties would require the ball mill to be operated at maximum percentage of critical speed ?
A.	Wet grinding in low viscous suspension.
B.	Wet grinding in high viscous suspension.
C.	Dry grinding of large particles (upto 1.25 cms).
D.	Dry grindng of large particles in un-baffed mills.
Answer» E.

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Actual operating speed of a ball mill may vary from 65 to 80% of the critical speed. Which of the following duties would require the ball mill to be operated at maximum percentage of critical speed ?

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