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- Technical Information
- Reference
- Formulas for Drilling
FORMULAE FOR DRILLING
CUTTING SPEED (vc)
*Divide by 1,000 to change to m from mm.
- vc (m/min)
- Cutting Speed
- D1 (mm)
- Drill Diameter
- π (3.14)
- Pi
- n (min-1)
- Main Axis Spindle Speed
(Problem)
What is the cutting speed when main axis spindle speed is 1350min-1 and drill diameter is 12mm ?
(Answer)
Substitute p =3.14, D1=12,n=1350 into the formulae
vc =(p ×D1×n)÷1000 =(3.14×12×1350)÷1000=50.9m/min
The cutting speed is 50.9m/min.
What is the cutting speed when main axis spindle speed is 1350min-1 and drill diameter is 12mm ?
(Answer)
Substitute p =3.14, D1=12,n=1350 into the formulae
vc =(p ×D1×n)÷1000 =(3.14×12×1350)÷1000=50.9m/min
The cutting speed is 50.9m/min.
FEED OF THE MAIN SPINDLE (vf)
- vf(mm/min)
- Feed Speed of the Main Spindle (Z axis)
- f(mm/rev)
- Feed per Revolution
- n(min-1)
- Main Axis Spindle Speed
(Problem)
What is the spindle feed (vf) when feed per revolution is 0.2mm/rev and main axis spindle speed is 1350min-1?
(Answer)
Substitute fr=0.2, n=1350 into the formulae
vf = fr×n = 0.2×1350 = 270mm/min
The spindle feed is 270mm/min.
What is the spindle feed (vf) when feed per revolution is 0.2mm/rev and main axis spindle speed is 1350min-1?
(Answer)
Substitute fr=0.2, n=1350 into the formulae
vf = fr×n = 0.2×1350 = 270mm/min
The spindle feed is 270mm/min.
DRILLING TIME (Tc)
- Tc (min)
- Drilling Time
- n (min-1)
- Spindle Speed
- ld (mm)
- Hole Depth
- f (mm/rev)
- Feed per Revolution
- i
- Number of Holes
(Problem)
What is the drilling time required for drilling a 30mm length hole in alloy steel at a cutting speed of 50m/min and feed 0.15mm/rev ?
(Answer)
Spindle Speed
n=(50×1000)÷(15×3.14)=1061.57min-1
Tc=(30×1)÷(1061.57×0.15)=0.188
=0.188×60=11.3sec.
What is the drilling time required for drilling a 30mm length hole in alloy steel at a cutting speed of 50m/min and feed 0.15mm/rev ?
(Answer)
Spindle Speed
n=(50×1000)÷(15×3.14)=1061.57min-1
Tc=(30×1)÷(1061.57×0.15)=0.188
=0.188×60=11.3sec.
