Calculation of the safe working zones for a crane gives overlaid zones based on the jib strength and crane stability together with nominal load ranges for the crane control system

摘要

To establish a safe working zone and a nominal load rating of a crane, or similar assembly with a load-carrying swing jib, the strength of the jib is taken into account for one safe working zone (41) and a second safe working zone (42) is established based on the stability of the machine. The two safe working zones (41,42) are overlaid to give the safe working zone for the crane. Similarly a safe load working zone is established for the weight loading based on the jib strength and the crane stability to give the safe load (Wo). The safe working zone and the safe loading range are incorporated into a safety control system with a display.