Fayat Group BOMAG BW 226 BVC-5, Service Manual

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1.3.1.1.7 Repair notes for cotter pins
Cotter pins
In places where cotter pins are used, these must be reassembled.
Cotter pins must generally be renewed after disassembly.
Cotter pins must be assembled as shown in the illustration, unless
specified differently.
1.3.1.1.8 Repair notes for screws and nuts
NOTICE!
Tighten screws and nuts in accordance with the
values in the following tables. Tightening torques
deviating from the ones in the table are specially
mentioned in the repair instructions.
Damaged screws must not be used again.
Recutting threads with thread cutters or taps
adversely affects the strength and leak tightness of
the screw joint. Damaged or corroded thread
pitches can cause incorrect torque value readings.
Self-locking nuts must generally be replaced after
disassembly.
The use of screws with too high strength can
cause damage!
n Nuts of a higher strength can generally be used instead of nuts
of a lower strength classification.
n When checking or retightening screw joints to the specified
tightening torque you should first relieve by a quarter turn and
then tighten to the correct torque.
n Before tightening you should slightly oil the thread, in order to
ensure low friction movement. This, however, does not apply
for self-locking nuts.
n Make sure that no oil or grease will enter into blind tapped
bores. The hydraulic power generated when turning in the
screw could cause breakage of the part in question.
1.3.1.1.9 Strength classes, metric screws and nuts
The strength classes (from 3.6 to 12.9) are specified for all strength
classes from a nominal diameter of 5 mm. The corresponding iden-
tification can be found where the shape of the screw permits it.
Fig. 34
Strength classes, metric screws
General – Maintenance and repair
BW 226 BVC-5 / BW 226 DI-5 48