A. Maximum feed size determines the required roll diameter
B. For hard material’s crushing, the reduction ratio should not exceed 4
C. Both the rolls run necessarily at the same speed
D. Reduction ratio and differential roll speed affect production rate & energy consumed per unit
of surface produced
Related Mcqs:
- Toothed roll crushers achieve size reduction by___________________?
A. Tearing (shear) and compression
B. Impact and attrition
C. Both A. & B.
D. Neither A. nor B. - Size reduction of _____________ is accomplished in steam heated rollers and roll crushers?
A. Resins
B. Gums
C. Hard rubber
D. Waxes - Pick out the wrong statement pertaining to the turbine agitator ?
A. Recommended peripheral speed for the turbine agitator is 200-250 metres/minute
B. Pitched blade turbine agitator gives only radial flow with complete absence of the axial flow
C. Generally, the diameter of the agitator is kept between l/3rd to l/6th of the tank diameter while
the blade length is l/4th of agitator diameter (with central disc, it is l/8th of the agitator
diameter)
D. Turbine agitator should be located at a height not less than one agitator diameter length from
the bottom. If the depth of liquid in the tank is more than twice the agitator diameter, two
agitators should be used - Gyratory crushers compared to the reciprocating jaw crushers__________________?
A. Have greater capacity per unit of discharge area
B. Crush intermittently
C. Are less suitable for coarse materials
D. Have less steady power consumption - As per Taggart’s formula, the capacity (kg/hr) of Jaw & Gyratory crushers (for gapes of 10 to 60 cms) is equal to (where, L = Length of feed opening, cms S = Maximum width of discharge opening, cms) ?
A. LS
B. 93 LS
C. 250 LS
D. √(LS) - The term ‘angle of nip’ is concerned with the operation of the ____________ crushers?
A. Jaw
B. Roll
C. Gyratory
D. None of these - Which of the following crushers can be considered as a combination of a jaw crusher and a roller crusher ?
A. Rod mill
B. Fluid energy mill
C. Gyratory crusher
D. Ball mill - Size reduction mechanism used in Jaw crushers is__________________?
A. Attrition
B. Compression
C. Cutting
D. Impact - Reduction ratio of crushers is the___________________?
A. Ratio of feed opening to discharge opening
B. Ratio of discharge opening to feed opening
C. Determining factor for minimum dia of the feed and the product
D. None of these - Pick out the wrong statement ?
A. Magnetic separation method can be employed to treat both dry & wet ores
B. Reduction ratio in crushing operation is defined as the ratio of minimum feed size to the
maximum product size
C. Gyratory crusher is used for coarse crushing
D. Screens are of stationary, moving and vibratory types
