778. An open structure of a grinding wheel is used for
A.Tough materials
B.Heavy cuts
C.Soft materials
D.All of the above

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779. Dressing of grinding wheels to restore sharpness is done by
A.Pumice stone dresser
B.Tool steel dresser
C.Diamond dresser
D.Sharp edged H.S.S. cutter

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780. In a Hard grade grinding wheel, the abrasives
A.Are hard
B.Are held more securely
C.Get lodged off easily
D.Are of fine grain

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781. When grinding wheels become loaded or glazed, they must be
A.Balanced properly
B.Aligned accurately
C.Trued
D.Dressed

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782. For grinding high tensile strength materials, following abrasive is recommended
A.Al2O3
B.SiC
C.Diamond
D.Corundum

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783. A centre type cylindrical grinder that permits swivelling the wheel head and head stock at an angle to the table ways is called a
A.Tool and cutter grinder
B.Universal grinder
C.Internal grinding machine
D.Bench grinder

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784. The first symbol in a grinding wheel code is the
A.Bond type
B.Abrasive type
C.Grain size
D.Structure

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