These are just a few of the items we discuss in our crane and rigging management class along with other key concepts. Rapid swinging-when the boom is moved rapidly the load will not be able to catch up due to inertia and the flexibility of the load line.Impact Loading-Rapid acceleration, sudden stopping, sudden load release, sudden load snatching, pick and carry operations.This radius if not properly accounted will cause a loss of capacity Boom deflection- overloading of boom causing increased radius.Lattice boom cranes create a vacuum of force as the wind blows through it

High winds can also cause a long boom crane to push over backwards. Wind-creates large surface area of the load causing the load to drift away from the crane.dented or bent lattice, cracked welds, rubber tire condition, etc will reduce the capacity of crane stability A crane’s capacity chart is based on a crane being level on firm surface Out of level conditions- 3degrees off level can reduce capacity by 50%.Improper counterweight configuration can change the stability of the crane either frontwards or backwards.Here is a list of other conditions that affect a cranes capacity: Ensuring a proper soils report is critical along with using outrigger pads that are large enough to reduce the pressure applied by the crane. Ground conditions become a large issue when the ground bearing pressure of the soil is less than the amount applied by the crane. For example, when an operator sets up a crane along the street with one side fully extended and another partially it creates stability issues when swinging over from one side to the other. Two of the most common situations are improper outrigger setup and poor ground conditions. These factors could be caused by a lack of awareness of the operator, supervisor, rigger, signalperson, and/or external forces exerted on the crane There are several factors that determine the exact capacity (such as boom length, counterweight, etc) However, even when a crane has a predetermined capacity at a given radius within a crane’s particular configuration there are still a few factors that affect a cranes capacity beyond what is stated on the load charts. Every mobile crane has a set capacity that it can hoist within a given radius of that crane.

Lifting radius of a crane