38
UTD.123.2019-10.00_EN
For the
axial fastening
it is possible to adopt
the system per fig. 7.10.1
and 7.10.2.
For sizes 64 ... 360,
when shaft end of
driven machine has no
shoulder, a spacer may
be located between the
retaining ring and the
shaft end itself (as in
the lower half of the fig.
7.10.2).
Parts in contact with the
retaining ring must have
sharp edges.
7.10 - Gear reducer axial fastening
Screw
32 ... 50
Screw
63 ... 161
Screw
200, 250
Helical and bevel helical
size 40, 50
Helical and bevel helical
size 63
Helical and bevel helical
size 180 ... 360
Parallel shaft
MR 3I 40, 50
Parallel shaft
MR 3I 63
Fig. 7.10.1a
Fig. 7.10.1b
The use of
locking rings
(fig. 7.11.1) or of
locking bushing
(fig. 7.11.2) will permit easier and more accurate
installing and removing and to eliminate backlash between key and keyway; friction system compatible
with ATEX design.
The locking rings or the locking bushing are fitted after mounting (for MR 3I 64 ... 81 insert the bushing
onto machine shaft end or into hollow shaft before mounting; pay attention when positioning the keyway).
Do not use molybdenum bisulphide or equivalent lubricant for the lubrication of the parts in contact. When
tightening the bolt, we recommend the use of a
locking adhesive
LOCTITE 601. For vertical ceiling-type
mounting, contact us.
In case of axial fastening with locking rings or bushing – especially when having heavy duty cycles, with
frequent reversals – verify, after some hours of running, the bolt tightening torque and eventually apply
the locking adhesive again.
Respect the tightening torques stated in the table 7.11.1.
Attention!
In applications with
travelling lifts
, the locking bush isn't sufficient anymore to grant a stable
keying of the hollow low speed shaft with machine shaft end, even when the axial fastening bolt is fixed
with locking adhesive. In these cases, it is necessary to key with hollow shaft and shrink disc. This is valid, in
general, also when there is a high frequency of startings and brakings motion reversal and when the inertia
ratio
J
/
J
0
is very high ( > 5).
7.11 - Gear reducer keying with key and locking rings or bush
Fig. 7.11.1
Fig 7.11.2
Tab. 7.11.1 - Tightening torque for axial fastening bolts with rings or locking bush
Gear reducer size
Series
A
32
40
50
63
—
80
—
125 160
—
200
—
250
—
—
—
—
64
81
126
161
G
40
50
—
63
80
81
100 125 140 160 180 200 225 250 280 320 360
64
321
Screw
UNI 5737-88 cl 8.8
M8
1)
M8
1)
M10
1)
M10 M10 M10
2)
M12
2)
M14
2)
M16 M20 M20
2)
M24 M24
2)
M30 M30
2)
M36 M36
3)
Tightening torque
M
S
[N m]
29
35
43
43
51
53
92
17
21
34
43
66
83
135
166
257
315
1) UNI 5931-84 cl. 8.8 (excluding MR 3I).
2) UNI 5737-88 cl. 10.9 (excluding worm gear reducer sizes 80, 81, 125, 126).
3) UNI 5931-84 cl. 10.9.
Helical and bevel helical
size 64 ... 160
Helical and bevel helical
size 400, 401
size 4000 ... 8001
Fig. 7.10.2
Fig. 7.10.3