12. HOISTING
Use a lifting beam of an appropriate
length when lifting large sheets and plate
structures. Make sure that there are
enough brackets for your lift. The brackets
help you avoid any deformation of
the item you are lifting. When installing
bulkheads or other parts, to prevent falling
have the crane take the weight of the
bulkhead until it is supported.
If necessary, use the guiding rope in order
to control the load and avoid manual
control e.g. in windy conditions.
Be careful that the lifting chain or wire
rope sling does not come loose from the
crane hook prematurely when you lower
the sheet. Keep behind the load in case it
falls.
Hoisting of plates
Think and choose safe and appropriate
lifting gear for each lift.
Use lifting gear with an intermediate carrier
to lift long plates. The carrier should
be wide enough to prevent the plate from
bending or slipping.
The following rule of thumb can be used
to calculate the weight of a plate: a plate
that is 1 meter long and 1 meter wide,
weighs 8 kg per each millimetre of plate
thickness.
For example: a plate that is 5 m x 2 m x 10
mm, weighs 5 x 2 x 10 x 8 = 800 kg.
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