To remain stable under various conditions is an important consideration for any type of crane, especially for the jib crane. The margin of stability of a jib crane while handling a load at any radius from the center of the jib crane, or working on a track on flat surface with the jib set at right angles, is defined as a percentage for additional load required to bring the crane to the point of tipping over. The stability of the jib cranes is often threatened under storm condition and under service conditions. Under storm conditions, the jib cranes in Australia are exposed to strong wind forces and they will face a 25% margin of stability.
The chance of a jib crane tipping over depends on the stability of the weight of the jib cranes. It is very important to determine the maximum tip-over capacity and to ensure that the operator will not pass it over. Every jib crane comes with a load chart that contain such information, so it is strongly recommended for every operator to read it before using the crane. For greater stability when loaded, the jib cranes in Australia use outriggers. The outriggers are essential for maintaining stability when the jib crane is loaded.
The jib cranes in Australia are very flexible, but also complex structural machines because their mechanical properties are not linear. This means that one accurate method for increased stability is difficult, or maybe impossible to invent. However, the researchers have found a solution for this problem by taking the maximum lifting capacity, the counterweight and the dead weight into consideration and established an equivalent mechanical model of a jib crane. The stability of this jib crane was analyzed by using the differential equation of deflection. This method for increasing the stability of the jib cranes is better than the traditional linear method.
