Fayat Group BOMAG BF 800-P Series, Руководство по обслуживанию

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General repair instructions
BOMAG 23 008 921 54
1.3
Strength classes of metric nuts
Nuts are differentiated by three load groups. Each
load group has a special designation system for the
strength class assigned, so that the load group can be
clearly identified.
Nuts for screw joints with full load capability (4, 5,
6, 8, 10, 12)
Fig. 9 Identification of nuts
In a connection with a screw, these nuts 1 (Fig. 9)
must be able to bear the full pre-load at the yield point.
Nut height above 0.8 d (d = nominal dimension).
Nuts for screw joints with limited load factor (04,
05)
The preceding "0" indicates that, due to their low
height, nuts 2 (Fig. 9) in this group are only able to
withstand the force of a screw to a limited extent.
Nut height below 0,8 d (d = nominal dimension).
Nuts for screw joints without specified load factor
(11H, 14H, 17H, 22H)
This standard contains strength classes (hardness
classes) for nuts 3 (Fig. 9), for which no load values
can be specified, e.g. because of their shape and di-
mensions, but which can only be classified by their
hardness.
Nut height below 0,5 d (d = nominal dimension).
Identification in clock system
Fig. 10 Identification of nuts in clock system
For small nuts (Fig. 10) the clock system can be used
for identification.
l
The 12 o'clock position is identified by a dot or the
manufacturer's symbol.
l
The strength class is identified by a dash (b).
Strength class of
nut Strength class of associated
screw
4 3.6, 4.6, 4.8
5 3.6, 4.6, 4.8
5.6, 5.8
6 6.8
8 8.8
9 9.8
10 10.8
12 12.8