Grinding is the process of removing metal by the application of abrasives which are bonded to form a rotating wheel.
It is used for good surface
Finishing, less grinding wheel wear, free of grinding cracks and burns.
PRINCIPLE
CONSTRUCTION
The grinding machine consists of a power driven grinding wheel spinning at the required speed and a bed with a fixture to guide and hold the work-
piece.
coolant is placed to cool the work piece so that it
does not overheat and go outside its tolerance.
Types of grinders
Belt grinder:
It is suitable for all kind of applications like finishing, deburring and stock removal.
Bench grinder:
Two wheels of different grain sizes for roughing and finishing operations and is secured to a workbench.
Cylindrical grinder
Surface grinder
USES OF GRINDING MACHINE
It is used for flat ,conical and cylindrical surfaces.
finishing internal cylinders or bores.
forming and sharpening cutting tools snagging or
removing rough projections from castings and stampings;
Advantages:
Work is supported rigidly.
Productivity is high.
Less skill is needed.
No chatter or deflection of work.
Disadvantages:
Work with several diameters cannot be handled well.
More time is involved in change over of centreless grinder.
Drilling
Creates a round hole in a workpart
Contrasts with boring which can only enlarge an existing hole
Cutting tool called a drill or drill bit
Customarily performed
on a drill press (b) drilling
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Used to slightly enlarge a hole, provide better tolerance on diameter, and improve surface finish
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REAMING.
Tapping
Used to provide internal screw threads on an existing hole
Tool called a tap
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Counterboring
Provides a stepped hole, in
which a larger diameter follows a smaller diameter partially into the hole
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Shaping and Planing
(a) Shaping, and (b) planing
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Similar operations
Both use a single point cutting tool moved linearly relative to the workpart.
Shaping and Planing
A straight, flat surface is created in both operations
Interrupted cutting
Subjects tool to impact loading when entering work
Low cutting speeds due to start-and-stop motion
Usual tooling: single point high speed steel tools
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Components of a shaper
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Open side planer
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