Fault analysis and countermeasures in hole machining
◆ault analysis and countermeasures in hole machining
Faults Countermeasures and check points
Cutting condition Tooling profile Machine tools, work pieces,
fixture of machine tools
Cutting speed
Cutting speed
Reduce feeding when drill bit is cutting in
Reduce feeding when it is drilled through
Stepping machining
 Cutting fluid
Apex angle
Back rake angle
Back taper
Margin width
Edge regrinding width
Core bit diameter
Tooling body diameter
Helical flute length
Installation precision of tools
Shortening of tools' overhanging length
Make a plane in cut-in position of work pieces
Improving firmness of work piece installation
Improving firmness of work piece installation
Reduce dilution rate
Increase flux
Increase oil supply pressure

increase

reduce1

increase

decrease
Body damage
● Damage of drill bit
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●Abnormal scratch of tooling holder
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Damage of knife point
●Damage of chisel edge
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  Damage at shoulder
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●Damage (little chipping)
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●Thermal cracking
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●Shell peeling in margin
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●Abnormal wear in margin
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●Abnormal wear in center
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Chip
●Chip jamming
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●Over long chip
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●Burning of chip
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Hole precision
●Large expansion
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●Large surfce roughness
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●Poor roundness
  There is rifling in hole surface
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●Bending, inclination
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●Produce burrs
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Others
●Vibration,trembling
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●Abnormal sound
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