How to choose a holder
How to choose a holder or what influences the main angle in the plan?
The main angle in the plan (angle Kr) – the angle between the plane cutting and working plane. For a cutter, this is the angle between the projection of the main cutting edge and the direction of feed movement.
At the moment, most of the world's cutting tool manufacturers have come to unify the choice of this angle. For various geometries of turning plates, as a rule, there is a certain choice of holders with some fixed value of this angle. So which holder should I choose in a particular case? Which choice will give the best result? Changing the angle in the plan how will the processing conditions change?
The main thing that affects the angle in the plan is the shape of the chip section. In turn, this affects the following characteristics:
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direction and value of cutting forces
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performance
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tool life
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roughness of the treated surface
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vibrations
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the ability to process various profiles of parts
Large angle in plan:
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the chips break on the tool (cutting edge) - lower resistance of the plate
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high cutting forces
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the resulting cutting force is directed towards the chuck, less vibration
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processing of non-rigid parts
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the tendency to form grooves on the plate
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chips "thick and narrow"
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roughing, low roughness
A small corner in the plan:
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chips break on the workpiece - higher tool life
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low cutting forces up to a certain value
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multidirectional cutting forces can cause vibrations
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the ability to work with a larger feed
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finer and finer chips
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processing of rigid parts
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less tendency to form punctures
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finishing treatment
How to determine the magnitude of the main angle in the plan by the designation of the holder?
In the ISO designation system for turning holders, the value of the main angle in the plan is encoded. In order to find it out, it is enough to look at the third letter in the designation of the holder and check with the table / catalog of the cutting tool manufacturer.
Example:
holder PCLNR 2525 M12. The letter L in this case shows that the main angle of the holder is 95.
Used literature:
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"Processing of materials and tools" Feldstein E.E., Minsk 2009
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Directories of cutting tool manufacturers
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