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Full text of "Modern Mechanical Engineering Vol-I"

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should be stopped in order to see that the crane brakes are in order, or that
the chain lifting-blocks will not run back. The piece should then be raised
another inch, in order to see that the crane can start lifting with the load
on it. It is unfortunately too often the case that the controlling arrange-
ments of an electrically operated crane will not allow the crane to start against
heavy load.

6.  The piece should then be lowered an inch, to see that the lowering
can be stopped, and that the piece is thus properly under control.     By
carrying out a few simple precautions of this kind much trouble and damage
can be averted, as, if the crane should fail to hold the piece, it can only run
down an inch or two at most.

7.  When everything is satisfactory, and the brake blocks, &c., adjusted
if necessary, the piece can be lifted into position, though care should always
be taken when lowering to see that the crane and lifting tackle are not subject
to shocks due to suddenly stopping.