BASIC OVERHEAD CRANE TERMS AND TERMINOLOGY
Overhead Crane Capacity
How is overhead crane capacity defined ? Overhead crane capacity is the pre-determined maximum weight that an overhead crane is designed to lift. The rated capacity of a crane is typically displayed on both the hook block and on the bridge.
Overhead Crane Span
What is meant by the span of an overhead crane? Overhead cranes typically travel on rails fastened to a runway system, the span or overhead crane span is defined as the horizontal distance between the rails.
Hook Height or Height of Lift
The hook height represents the required dimensions from the crane hook to the floor when the crane hook is at its highest position. This vital measurement determines how high the runway must be from the floor and directly related to the clear interior height of the building or structure.
Lift, Trolley, and Bridge Speeds
These speeds are typically represented in FPM (feet per minute) and indicate the rate at which the bridge, trolley, and hook travel at The speeds can be pre-set at a single speed or two speeds; high and low. Another popular and effective option to control the motions of your crane is to use a VFD (variable frequency drive) ** which allows for the customization of speeds while also creating a soft start and stop.
Crane Lift Speed
Crane lift speed defines the rate at which the bridge or trolley travels, or at which the hoist lifts, usually in feet per minute or FPM. Crane lift speed is variable with a Variable Frequency Drive (VFD). This also provides the capability to overspeed the hoist to decrease cycle times when the host is lightly loaded.