Servomech S.p.A.
01.05.TR.E - Rev. 02 DD (M/Y) 12/19
21
Dimension H [mm] with new bronze nut
MA 5
MA 10
MA 25
MA 50
MA 80
MA 100
MA 200
MA 350
2
2.5
3
3.5
4.5
6
6
8
Dimension H [mm] with new bronze nut
SJ 5
SJ 10
SJ 25
SJ 50
SJ 100
SJ 150
SJ 200
SJ 250
SJ 300
SJ 350
SJ 400
SJ 600
SJ 800
SJ 1000
—
2.5
3
3.5
4.5
6
6
6
6
6
6
7
7
8
Table 6.6 – Dimension H with new bronze nut
Figure 6.7 – working nut thread wear level
When the distance H between the working nut and the safety nut reaches a quarter of the thread
pitch (half of the dimension indicated in Table 6.5), it indicates a CRITICAL SITUATION: STOP THE
SYSTEM AND REPLACE THE WORKING BRONZE NUT.
6.8
Adjustable axial backlash device RMG
Available only for travelling screw jacks MA Mod.A Series.
The adjustable backlash device RMG is a manual device which
reduces axial backlash between acme screw and bronze nut,
allowing high positioning precision. With the RMG device it is also
possible to compensate the wear of the nut thread.
In order to adjust the axial backlash, please follow below
instructions:
Release the grub screw (P) placed on the side of the
housing, which locks the ring nut (G).
With a compass wrench act on the ring nut (G). By turning
the ring clockwise, the axial backlash will be reduced; by
turning the ring counterclockwise it will be increased.
Check the axial backlash by pushing-pulling the acme screw.
WARNING: DO NOT completely eliminate the axial backlash with an excessive clockwise tightening
of the ring nut. This will cause locking and damaging of the acme screw and nut.
Once reached the correct axial backlash, lock the ring nut (G) with of the grub screw (P). Between
the grub screw and the ring nut, a copper plug is placed to prevent the thread of the ring nut from
being damaged.
