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10. GRINDING

•Grinding has two main uses,

-as a surface finishing process for flat or cylindrical features that have already been cut.

-to cut complex surfaces with high tolerances or hard materials.

•The basic process involves an abrasive wheel spinning at high speed that is brought into contact with the work surface, thus giving a smooth finish.

10.1 OPERATIONS

Surface Finish

Formed Grooves

Internal (rounds)

10.2 MACHINE TYPES

• Typical categories of grinders include, Surface

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Cylindrical

Internal

Center

Centerless

Jig

10.2.1 Surface

•Surface grinders have a few basic types,

-Horizontal Spindle with Reciprocating Table

-Horizontal Spindle with Rotary Table

-Vertical Spindle with Rotary Table

-Vertical Spindle with Reciprocating Table

10.2.2 Center

• With centers parts are mounted so that they may rotate about fixed centers and then ground externally.

10.2.3 Centerless

•Centerless grinding is popular as a high speed, low cost operation.

•In this operation there is a grinding wheel and a governing wheel. The part sits between the wheels and is ground by the grinding wheel. The governing wheel acts to slow the rotation of the part so that it does not spin at the same speed as the grinding wheel and reduce the surface speed of the grinding operation.

	part
grinding	governing
wheel	wheel

blade