Operating Manual
Tangential Rolling System T18F - T27F
9
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If smaller thread lengths are required, recessed rolls can be used, if necessary. It is
also necessary here that the roll width A is at least the screwable thread length on the
workpiece plus 2x thread pitch P. The standard dimensions specified in the table are
preferably to be used. When placing orders for rolls include details of the minimum
and maximum possible roll width.
Table 1: Standard roll width version
Rolling head
Roll widths A [mm]
T18F
6
8 10 12 14 16 18 21.5
T27F
8 10 12 14 16 18 20
22 24 26 28 31
The forces which occur during the thread rolling process vary depending on the tensile
strength of the workpiece, the major diameter d of the thread and the thread pitch P.
Therefore, not all thread sizes can be rolled with the maximum roll width. The maxi-
mum rollable thread length L can be estimated using the formulas from the following
table. The following is to be used:
L = rollable thread length
[mm]
P = thread pitch
[mm]
d = major diameter of the thread
[mm]
All values are indicative and may vary in individual cases.
Table 2: Maximum rollable thread length L
Rolling head
Tensile strength of the material [N/mm
2
]
< 500
500 … 700
700 … 900
> 900
T18F
L = 580.5
______
P · d
L = 483
_____
P · d
L = 446
_____
P · d
L = 414
_____
P · d
T27F
L = 1255.5
_______
P · d
L = 1046
_____
P · d
L = 965
_____
P · d
L = 896
_____
P · d
3.5
Position of the thread run-out
The thread can be produced on the workpiece very close to a shoulder, or similar. In
such cases, corresponding safety distances must always be maintained (see Figure 1).
The thread roll (1) must have the safety distance c to the shoulder of the workpiece (2).
The screwable thread begins at the distance a
1
from the shoulder.
The following applies: a
1
= b + c [mm]
Lead chamfer angle
Thread lead b
Distance a
1
45°
0.6 · P
1.1 · P
60°
P
1.5 · P
Standard
70°
1.55 · P
2.05 · P
In standard cases (lead chamfer angle = 60°) the thread lead b on the roll corresponds
to the thread pitch P. The safety distance corresponds to c = 0.5 · P.
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