Stepped boring of gearbox housing

Task

  • Workpiece: Gearbox housing
  • Diameter/tolerance:
    28-0.029/-0.042;
    33 0/+0.2;
    35 – 0.035/-0.051
  • Material: Aluminium
  • Bore length: 57 mm
  • Bore type: Blind hole drilling, open to
    the side
  • Circularity: 0.013 mm
  • Preliminary machining Ø: allowance
    approx. 2 mm in diameter
  • Preliminary machining type: Casting
  • Machine: CHIRON FZ 15
  • Spindle adapter: ISO 40 / DIN 69871AD

 
Solution

  • Tool designation: 5 step drill
  • Tool holder: DAH-81
  • Bevel: Special face cuts
  • Cutting material: PKD
  • Internal cooling IKZ: Dry machining,
    compressed air internal cooling
  • Number of cutters: 4
  • Cutting speed vc: 220 – 534 m/min
  • Speed n: 2500 min-1
  • Feed per tooth fz: 0.075 mm
  • Feed Vf: 750 mm/min

Customer benefits

  • Travel: 500 m
  • Surface achieved: Ra 0.4
  • Circularity achieved: 0.011 mm
  • Saving: Significant reduction of the
    overall machining time
 

5-stage reamer