Boom's Anti-Backward-Tipping System Simulation In Large-scale Crawler Crane

Luffing rope and pulling-cable which are in flexible luffing system of the crawler crane can only be pulled but not bear the pressure. They can not play a supportive role when the boom tips backward. Once the crawler crane unloads suddenly, especially when it works in the long boom case with a big working-angle, the accident of boom's backward-tipping will happen easily by reason of the elasticity effect of the boom, the pulling-cable and the luffing rope. Therefore the anti-backward-tipping system of the crawler crane is of great importance for the stability and security of the complete machine. With the crawler crane developing toward largenning, boom's length and hoisting tonnage arc becoming larger and larger, with the result that the research on the boom's anti-backward-tipping system is much more significant. However, boom's anti-backward-tipping system belongs to complex nonlinear system, resulting in its dynamic characteristics could not be analyzed by the conventional static analytical method; meanwhile, boom's backward-tipping is very dangerous, making the physical experiment impossible.Forms and principles of anti-backward-tipping system in crawler crane is researched in this article, in the background of QUY500 crawler crane developed by Dalian University of Technology and Foton Lovol International Heavy Industry Co.Ltd; flexible boom's virtual prototype structural model is founded basing on the rigidity-flexibility modeling techniques, in which the dynamic simulation software ADAMS is applied to use ADAMS/View module coupling with three-dimensional entity design software Pro/E and finite element software ANSYS. With the use of ADAMS/Hydraulics module, the anti-backward-tipping hydraulic system model is established to realize machine-hydraulic joint simulation for the virtual prototype of crawler crane.Through the kinetic simulation of loading slowly and unloading suddenly in the main boom case with a big working-angle, kinematic and kinetic characteristics of the boom in the effect of anti-backward-tipping system when unloaded suddenly is analyzed, anti-backward-tipping function impact in the same case with different boom length is contrasted, throttle-hole of the unti-backward-tipping hydraulic system is optimized via simulation.Under the circumstances of founding the virtual prototype of crawler crane and simulating the case of unloading suddenly, mechanical and dynamic characteristics of the anti-backward-tipping system in crawler crane is analyzed and investigated and the correlated parameters of the anti-backward-tipping system is optimized, providing theoretical basis and research measures for the anti-backward-tipping system design in the crawler crane, especially in the large-scale crawler crane.