Operation
Version 1.0 - 2020-12-22
137
Translation of original instruction
TU2506VB
EN
T
U
2506V
B_GB
_4.
fm
Bolts and nuts with large thread diameters, deviating thread pitches or special types of thread,
right-handed and left-handed threads may be produced by threading. For this manufacturing
there are as well tool holders and drill rods with exchangeable indexable inserts (one-edged or
multiple-edged).
4.18
Thread types
Img.4-27: die
Img.4-28: screw tap
Img.4-29: Tap external thread
Img.4-30: Tap internal thread
Designation
Profile
Code letter
Short term (e. g.)
Application
ISO-threads
M
UN
UNC
UNF
UNEF
UNS
M4x12
1/4" - 20UNC -
2A
0.250 - UNC - 2A
Ma
ch
ine
tool
s
an
d g
ene
ra
l
me
chani
cal eng
inee
ring
UNJ
UNJ
1/4" - 20UNJ
Aircraft i
ndustry a
nd
aerospa
ce indu
stry
Nut
Bolt
Nut
Bolt