Operator’s Manual Crane Operator’s Manual for for Crawler Crawler Crane 履带起重机操作手册
CAUTION (1) Never stand directly underneath a lifted load. Observe the instruction “No person is allowed to stand under the boom when the crane is operated”.
(2) Tail the load by tagline with proper force. Otherwise the crane may topple over. (3) Never wrap the tagline around your body or limbs.
3.3.7 Load center of gravity a)
The center of gravity The center of gravity of an object is the point at which the weight of the object acts as though it were concentrated. All loads to be lifted must be equipped with lifting device and rigging above the center of gravity in order to prevent tipping and possible hazards to equipment and workers. The lifting force must always be located above the center of gravity. Exert a straight vertical pull the hook and below the point of attachment for any rigging. A center of gravity above the hook is unstable and will cause the load to flip as the load will attempt to ‘find’ the center of gravity during lifting process. Similarly, loads which are not balanced horizontally can slip from the rigging. The overall stability of the load is a combination of balance with respect to center of gravity, distribution of weight, and proper rigging practices.
b)
To determine the center of gravity The center of gravity of a regularly shaped object may be estimated accurately by determining its approximate center. Finding the center of gravity of irregularly-shaped objects can be more difficult, but it is necessary. A load will always hang from its attachment point through the center of gravity. It is important to visualize this before making a lift.
ZCC1100H Crawler Crane
3-27
Safety Guidelines
to prevent swinging of the load. In all crane lifts, the center of gravity must remain below
安 全 准 则
