   The center of gravity is the point at which an object’s entire mass can be assumed. When lifting any item it is important to have the hook on the crane positioned directly over the center of gravity. This will allow the load to be lifted straight up without tilting. Loads should not be lifted until they are properly balanced. For many items the object to be lifted is symetrical, so the center of gravity is in the center of the object. Many other large pieces of laboratory equipment have lifting eyes, or threaded holes for lifting eyes already if place. If the object has engineered lifting postions, use them. Some pieces of equpment have the center of gravity marked on the top of the equipment. A large fraction of other items consist of multiple pieces combined into an instrument. In these cases the center of gravity cannot be determined without lifting the instrument. In such a case, it may be necessary to adjust the rigging several times before getting the hook located above the center of gravity. When slowly trying to lift an item, if it tends to tip, the rigging needs to be adjusted so that the hook is closer to the lowest corner of the item. This process should be repeated until the item lifts without tilting. |