4 Information on crane operation
4.4 During crane operation
Safety manual
3 303 022 en
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4.1
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Sunshine
One-sided direct sunshine can lead to a temperature difference between the left
and the right main boom sides. This results in a different length extension.
A lateral deformation of the main boom is the result. The degree of deformation
depends on the actual temperature difference and the current main boom length.
Assuming a temperature difference of 30° and a system length of 60 m, defor-
mation without load of up to 1 m can occur. This would be a deformation of 1.7%.
An excessively deformed main boom could be overloaded!
Or it could suffer hidden damage that could result in overloading the main boom
during subsequent lifting operations with permissible deformation or reduce the
service life of the main boom!
Make sure that the maximum permissible values for lateral deformation are not
exceeded.
Risk of accidents!
– Preventive measures
If possible, turn the superstructure to a (park) position where both main boom
sides are heated evenly to prevent deformation.
– Before any lifting with deformed main boom
The main boom must be telescoped out to the length required for the lifting
operation. The maximum permissible lateral deformation of the
unloaded
main
boom (with reeved hook block) is 1% of the main boom length.
– Check the deformation before lifting.
– Only lift the load if the current deformation is permissible.
– For any lifting with deformed main boom
The maximum permissible lateral deformation of the loaded main boom
is 3% of the current boom length.
– Check the deformation during lifting.
– Put the load down before the maximum permissible deformation is
exceeded.
– Reduce additional, dynamic influences by wind.
– Carry out crane movements at minimum speed only.
