FRAISES ET ALÉSOIRS EN HSSCo-PM
ET CARBURE - OUTILS SPECIAUX

IIn this section we mention some of the more popular problem related to the milling operations. Very often the careful analysis of the process, the tool and the machined surface of the chip product allows to act in order to solve problems or to optimize the use of the tool. We underline how the cost of processing depends heavily on the life of the tool, the finishing, the reduction of the waste and downtime for controls, settings and tool changes. We are convinced that a careful selection of the tool is one of the essential process to have a good productivity.

Here below is a list of typical problems that occur during a milling operation.

 

edge chipping

Possible corrective actions

  • Decrease feed per tooth
  • Increase the cutting speed
  • Cutter with carbide too fragile, change with carbide tougher
  • Check rigidity of the machine
  • Check run-out of the cutter
  • Ensure appropriate choice of cutter geometry
  • Difficulties in the evacuation of the chip: please test the cutter path or direction and pressure of the refrigerant

tool wear

Possible corrective actions

  • Reduce the cutting speed
  • Increase feed per tooth
  • Cutter with carbide material of low resistance to wear, please use carbide with most features of wear resistance
  • Ensure appropriate choice of cutter geometry
  • Ensure appropriate choice of the coating

Edge cratering

Possible corrective actions

  • Reduce the cutting speed
  • Decrease the feed per tooth
  • Cutter with carbide material of low resistance to wear, please use carbide with most features of wear resistance
  • Increase the flow/pressure refrigerant
  • Ensure appropriate choice of the coating

Up edge

Possible corrective actions

  • Decrease the depth of cut
  • Increase the cutting speed
  • Increase feed per tooth
  • Increase flow/pressure refrigerant

Poor work piece surface

Possible corrective actions

  • Decrease feed per tooth
  • Decrease the depth of cut
  • Increase the cutting speed
  • Check the rigidity of the machine
  • Use a cutter with helix angle sharper
  • Use a cutter with greater number of cutting edges
  • Check the run-out of the cutter

Presence of vibration during machining

Possible corrective actions

  • Decrease the depth of cut
  • Reduce the cutting speed
  • Check the stability of the machine
  • Check the stability of the piece
  • Check the refrigerant density
  • Use an end mill with more teeth
  • Use a shorter cutter
  • Use a cutter with irregular division
  • Decrease the rake angle

Presence of chips on the piece

Possible corrective actions

  • Decrease feed per tooth
  • Decrease the depth of cut
  • Decrease the phase of the cutting edge

Overload the machine

Possible corrective actions

  • Reduce the cutting speed
  • Decrease feed per tooth
  • Decrease the depth of cut

Do not perpendicular wall

Possible corrective actions

  • Check the concentricity of the cutter on the machine
  • Reduce the cutting speed
  • Decrease depth and width of cut
  • Decrease the total length
  • Use cutter with more teeth

No dimensional accuracy

Possible corrective actions

  • Decrease depth of the cutting pass
  • Improve the rigidity of the spindle and the clamp
  • Use cutter with more teeth

Chip forming ball

Possible corrective actions

  • Reduce feed or speed
  • Use cutter with less number of teeth
  • Increase the flow of the refrigerant
  • Try different geometries of the cutting edge

Flash

Possible corrective actions

  • Anticipate regrinding
  • Correct the parameters and the cutting angle

Broken cutter

Possible corrective actions

  • Reduce speed and feed per tooth
  • Use a shorter cutter
  • Anticipate regrinding
  • Check the spindle
  • Check the run-out

 
 
 
 
 
WARNING: the suggestions given are for guidance only and do not guarantee the resolution of the problem that could be created by multiple causes. In order to have the confirmation of the selection tool and analysis of the problem, please contact the RIME technical department for a more precise answer.