Page 245 - Fanar

Technical Information i

5. FORMING TAPS

5.1. Forming tap construction elements

A
D1 r D3 D2

D4

a

L5
L3 L4

L2
L1

60°
A
A-A P
K
r m

L1- total length
L2 - thread length
L3 - useful length
D5
L4 - length of driving square
L5 - chamfer length
D1 - thread diameter
r - straight flute
D2 - shank diameter κ - chamfer angle
D3 - neck diameter α - angle of thread
P - pitch of thread
D4 - (chamfer) point diameter
m - width of land
D5 - web (core) diameter a - size of square

5.2. Types of forming tap chamfers

Chamfer length presented in
Symbol Sketch Angle
the quantity of the thread coils

K 2÷3 P

C 2 ÷ 3 P 15°

K 1,5÷2 P

E 1,5 ÷ 2 P 23°

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