EXPLAINING THE S CLASSIFICATION AND HC/HD CLASSES

 

The structural calculation of a knuckle boom crane is based on four criteria: geometry, applied loads, material, and safety factor. Based on these, the EN 12999 standard establishes limitations for safety factor, wind force, climatic factors, and dynamic effects.

 

 

It indicates the number of full-load operating cycles the crane can withstand: an S1 crane is designed for 32,000 cycles, the same crane in S2 for 64,000. Under the same load, S2 doubles the service life of S1. The standard, along with EN 13001, requires this information to be declared in the user and maintenance manual.

 

 

HC classes define the type of mounting—for example, truck-mounted or stationary—while HD classes describe how the lifting movement is controlled: ranging from ON/OFF systems to proportional controls and systems that automatically limit dynamic effects. These classes help determine how the crane behaves when handling a load in motion, as well as the performance levels it can safely achieve under actual working conditions.

 

 

The "S" class indicates how long the crane will last; the HC/HD classes indicate how it performs while working. Both, mandatory in the catalog since 2022, provide a much more complete picture than any isolated tonnage figure.

 

→ We expand on each class, with tables, in our technical guide.