Self-propelled jib cranes are most widely used in construction for loading and unloading operations, the main advantage of which, among other types of cranes, is high mobility. The share of self-propelled jib cranes in construction is more than 60%.
An important element of the construction of self-propelled jib cranes is the boom, the strength of the structure of which largely depends on the safety of the crane and the prevention of accidents that lead to injuries and death of maintenance personnel. When calculating the crane boom for strength, power of electric motors for changing the departure of the boom and turn, the brakes of these mechanisms must take into account all types of loads acting on the rotary boom with load, including inertial, which account for a significant share among other loads.
The paper considers the calculation of the following moments of inertia forces: created by vertical inertial forces during braking of the load lifting mechanism; arising from the mass of the load and the boom during the period of unstable movement of the mechanism of change of the boom departure during start-up and braking; the load created by centrifugal force which arises at rotation of a rotary part of the crane; arising from the mass of the load and the boom during the period of unstable movement of the crane rotation mechanism. When calculating these moments of inertia, the following initial data are taken into account: geometric dimensions of the crane, weight and length of the boom, weight and height of the load, angle of the self-propelled crane in the construction area, radius of the crane boom, boom and load speeds, start and braking times mechanisms for lifting the load, changing the departure of the boom and turning the crane.
The obtained dependences for determining the inertial loads of the rotary boom of a self-propelled crane will allow more accurately taking into account multiple factors to calculate the values of these loads in order to perform strength calculations of the boom, selection of components for lifting, changing the boom and turning the crane.
Determination of Inertia Forces Acting on Break Bulk Cargo en Route
