Technical Information
Threading
Partial Profi le Full Profi le Multi-Tooth Profi le
Tooth profi le with universal
profi le shape: Tooth profi le with full profi le shape
including tooth height: Multi-tooth full profi le
generally with 2–3 teeth:
• 55° or 60° without cutting edges
for the tooth tapers. • For bur-free, precise threads in the specifi ed
pitch. • Highly productive threading with
fewer passes and longer tool life.
• Reduced inventory. • General application. • For various pitches in a limited range. • Machining allowance for outside/core diameter
around 0,1–0,15mm. • Requires a rigid setup and long thread
pass through.
• Preferably one time production.
• Minimum clearance width approximately
1.25 x E as per indexable insert
dimensions table.
• Major/minor diameters must be
accurately pre-turned.
Formulas
Legend
Metric Formula
m/min
RPM
given
D (mm)
RPM
D (mm)
m/min
formula
/ x D
x RPM
m/min =
1000
m/min = metres per minute
RPM = revolutions per minute
D = part diameter
/ = 3.1416
m/min x 1000
RPM =
D x /
Maximum Cutting Speeds Flank clearance
On older machines, cutting speed is often limited by the maximum
travel speed mm/min of the tool allowed by the machine. a
a
`
_
Check your maximum speed with the following formulas:
metric formula: maximum cutting speed (m/min) =
part diameter (mm) x 3.14 x (1/pitch) x max mm/min
1000mm
F86
=
=
=
=
arctan (sin`/2) * tan(_))
side (fl ank) clearance
included angle of thread form
radial inclination angle
Thread Angle External UN & ISO 60 5.3
Internal
8
BSW 55 4.8 7.3
TR 30 2.6 4
ACME 29 2.6 3.9
AMBUT 7 .6 .9
AMBUT 45 4 6
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