Tc 9-524 fundamentals of machine tools

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TC 9-524
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TC 9-524
STANDARD SHAPES OF GRINDING
Tensile Strength of Material
WHEEL FACES
The tensile of material to be ground is the main factor in the
selection of the abrasive to be used. Two types of abrasives
Figure 5-10 illustrates standard shapes of grinding wheel
faces. The nature of the work dictates the shape of the face to
be used. For instance, shape A is commonly used for straight
cylindrical grinding and shape E for grinding threads.
SELECTION OF GRINDING WHEELS
Conditions under which grinding wheels are used vary
considerably, and a wheel that is satisfactory on one machine
may be too hard or soft for the same operation on another
machine. The following basic factors are considered when
selecting grinding wheels, though it should be understood that
the rules and conditions listed are flexible and subject to
occasional exceptions.
are suited to different materials as shown below.
Silicon Carbide
Gray and chilled iron
Brass and soft bronze
Aluminum and copper
Marble and other stone
Rubber and leather
Very hard alloys
Cemented carbides
Unannealed malleable iron
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TC 9-524
Aluminum Oxide
Carbon steels
Alloy steels
High speed steels
Annealed malleable iron
Wrought iron
Hard bronzes
Factors Affecting the Grain Size
Grain size to be chosen when selecting a grinding wheel
depends upon the factors described below.
The softer and more ductile the material, the coarser the
grain size.
The larger the amount of stock to be removed, thecoarser
the grain size.
The finer the finish desired, the finer the grain size.