Общий каталог Yamawa 2021 - страница 639

5. Tapping Torque
Intro
Tapping Torque of Cutting Taps
SP The torque starts increasing as the threads of thechamfer enter the workpiece material. It reaches the highest level when all the threads of the
chamfer cut into workpiece material, and is in plateau until the chamfer cuts through the workpiece. After that, the torque decreases until the
end of tapping.

SL Tapping Torque Equation for Cutting Taps Table 1 Specific cutting resistance of each material
tanθ Materials to be cut Specific cutting resistance kc N/mm2
Tc = . x kc × K(D-Do)² × (D+2Do) Material symbols Hardeness N/mm2
24000
5t44-2 133HB 3700
PO Tc : Tapping Torque (Nm) Ck 15 141HB 3600
kc : Specific cutting resistance (N/mm2) Ck 35 162HB 3700
K: Correction coefficient depending on tap geometry and chips Ck 45 188HB 3900
D: Nominal Diameter of Tap (mm) Ck 60 188HB 4000
Do : Bored hole diameter (mm)
ST θ: Thread half angle (°)
42 CrMo 4 193HB 3600
30HRC 4900
kc and K : Refer to Table 1 and Table 2 40HRC 5500
X 6 CrNi 18 10 209HB 4200
C 105 W2 175HB 5300
ROLL
CnZn40 - 2300
G-AISi8Cu3 - 1300
GG-25 193HB 2900
CARBIDE
Table 2 Correction coefficient depending on each tap geometry
Coefficient K
Materials to be cut
LONG Steel Cast iron + Alluminium alloys Brass
Kinds of tap coarse fine coarse fine coarse fine
Straight fluted tap 5P 1.35 1.15 1.25 1.08 1.60 1.12
Straight fluted tap 1.5P 1.43 1.50 1.30 1.25 1.68 -
HAND Spiral fluted tap 1.15 1.25 1.05 1.10 0.85 -
TAPS Spiral pointed tap 0.95 1.00 0.80 1.00 0.75 1.00


EG (STI)

SPECIAL
THREADS,
GAUGES
THREAD
MILLS

DIES

CENTER
DRILLS

Technical
info

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