Page 716 - Master Catalog 2017, Inch

Technical Information
Threading

Partial Profi le Full Profi le Multi-Tooth Profi le

Tooth profile with universal Tooth profile with full profi le shape Multi-tooth full profi le

profi le shape: including tooth height: generally with 2–3 teeth:
• Reduced inventory. • For bur-free, precise threads in the • Highly productive threading with fewer
• For various pitches in a limited range. specifi ed pitch. passes and longer tool life.
• General application. • Requires a rigid setup and long thread
• Major/minor diameters must be
accurately pre-turned. • Machining allowance for outside/core diameter pass through.
around .004–.006".

Formulas

Inch Formula Legend
to fi nd given formula IPM = inch per minute
SFM = surface feet per minute
/ x D
D (inch) m/min = meters per minute
SFM SFM = x RPM
RPM
12" RPM = revolutions per minute
D = part diameter
SFM x 12" / = 3.1416
D (inch)
RPM RPM =
SFM
D x /
Metric Formula
to fi nd given formula
/ x D
D (mm)
m/min m/min = x RPM
RPM
1000
m/min x 1000
D (mm)
RPM RPM =
m/min
D x /
Maximum Cutting Speeds Flank clearance
a arctan sin `/2) * tan(_))
On older machines cutting speed is often limited by the maximum travel speed a = side (fl ank) clearance
(IPM or mm/min) of the tool allowed by the machine. Check your ` = included angle of thread form
maximum speed with the following formulas: _ = radial inclination angle
inch formula: maximum cutting speed (SFM) =
part diameter (inch) x 3.14 x TPI x max IPM
12" Thread Angle External Internal
metric formula: maximum cutting speed (m/min) =
part diameter (mm) x 3.14 x (1/pitch) x max mm/min UN & ISO 60 5.3 8
1000mm 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

F90 widia.com

V
Th
di
F090 F091 Mi
i
i
WID M
16 T
L WID_Master16_Turning_Threading_F090_F091_Minch_REBRAND.indd 90 h REBRAND O b 15 2015 8 41 AM 10/30/15 2:14 PM