Dinamička analiza portalne dizalice pri većem broju pokreta kolica i korisnog tereta

Abstract

Izučava se dinamičko ponašanje realne portalne dizalice izložene većem broju pokreta kolica i korisnog tereta. Razvijen je poseban numerički postupak koji je primenjen metodom konačnih elemenata na simulaciju različitih načina kretanja glavne grede. Rezultati jasno pokazuju da pomeraj krana, naročito longitudinalni, u velikoj meri zavisi od ubrzanja kako u početnoj tako i u fazi zaustavljanja, čemu su kolica izložena za vreme kretanja glavne grede krana. Poslednji deo rada prikazuje simulaciju iznenadnog zaustavljanja kretanja kolica i potonjeg ljuljanja korisnog tereta; u ovom slučaju, dužina užeta koje zaustavlja koristan teret na kolicima ima glavnu ulogu u određivanju kretanja i maksimalnog longitudinalnog pomeraja dizalice.

The aim of this research is to study the dynamic behaviour of a real gantry crane subjected to the actions induced by the trolley and payload movement. A specific numerical procedure was developed and implemented in the finite element method in order to simulate different trolley movement modes on the crane's main beam. From the results, it is clear that the crane displacement, especially the longitudinal one, is strongly dependent on the acceleration both in the starting phase and in the stopping phase to which the trolley is subjected during its movement on the crane main beam. The last part of this research simulates the sudden stop of the trolley movement and subsequent payload swinging; in this case, the length of the rope that suspend the payload to the trolley has a fundamental role in the trend and maximum longitudinal crane displacement value.