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
 
                           
 
 
Abnormal scratch of tooling holder
 
                         
   
   
Damage of knife point
Damage of chisel edge
   
                 
         
   

  Damage at shoulder
     
               
     
       
Damage (little chipping)
 
     
           
       
 
 
Thermal cracking


       

   


               
Shell peeling in margin
         
       
                   
Abnormal wear in margin

       

                 
       
Abnormal wear in center

       

                           
Chip
Chip jamming


   
 

         
             
Over long chip


       
         
             
Burning of chip

         
                           
Hole precision
Large expansion
   
         
     

 

       
Large surfce roughness



   
       

         
     
Poor roundness
  There is rifling in hole surface

 
         

   
   

       
Bending, inclination
   
 
         

     
 

   
Produce burrs
 
           
     
   
         
Others
Vibration,trembling
 
                   
       



Abnormal sound

                 

                 
   
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