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USER GUIDE
THREAD DRILLING Spindle Speed (min ) F = feed/rev ipr
General - Calculations - Inch
-1
material specific cutting force
=
kpsi
Kc
v c ∙ 12
in
point to workpiece before feeding
=
H
n=
π ∙ D
diameter of hole
=
D
in
L
=
in
depth of hole
Cutting Sfm
=
%
machine efficiency
Η
π ∙ D ∙ n
}
vc =
= 90º
180° bottom drills
K
12 Inh = cost/machine hour $/h
Sin k = 1 DR...
Table Feed (in/min)
K = 70º } 140° point angle drills
vf = f ∙ n Sin k = 0.94 SCD.., DIn.., DCN..
Material Removal Rate (in /min)
3
Q= v f ∙ π ∙ D 2
4
Power Consumption (hp)
Q
Pc = ∙ kc
396 ∙ η
Torque
Mc = f ∙ kc ∙ 1000 ∙ D 2 ∙ sin k
8
Feed Force (approx.) (lbf)
D
Ff = 700 ∙ ∙ f∙kc∙sin k
2
Machining Time (min/piece)
L+h
Tc =
vf
Machining Cost ($/piece)
Cc = I nh ∙Tc
60
ISCAR
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