549 13 th International Research/Expert Conference ”Trends in the Development of Machinery and Associated Technology” TMT 2009, Hammamet, Tunisia, 16-21 October 2009 STUDYING DYNAMIC EFFECTS ON CRAWLER CRANES FOR THE CASE OF ROTATIONAL MOTION USING SIMULATION APPLICATIONS Ilir Doçi, Musli Bajraktari, Beqir Hamidi University of Pristina, Faculty of Mechanical Engineering Pristina Kosova ABSTRACT Crawler cranes belong to the family of mobile cranes that have complex structure with big dimensions and mechanisms and high security requests. Main cycles of the work of Crawler Cranes can be divided into: lifting and lowering the working load, boom lifting and lowering, rotation (slewing) around its vertical axes in 360º, and translational movement forward/backwards. In this workshop, we are going to simulate the work of crawler crane while rotating around its vertical axes when fully engaged with load, which hangs in some height. The aim is to see the effects of dynamic forces (or moments) in the crane’s construction during this work cycle, particularly at the start and end of the rotation when working load swings. Reasons for doing this study are occasions of crane instability, while the crane rotates and load swings. We will research the effects of angular speed and workload swaying (swinging) in overall stability of crawler crane by looking for results of swaying angles, dynamic momentums and tensions in cables. By using the modeling applications and applying simulations [3], we are confident that we will have better view of occasions in case of crane rotation and some conclusions for enforcing security and design rules in order to avoid instability and overturning. To do this study, we designed a “virtual crawler crane” using model design and simulation applications and applied simulations based on input parameters and dimensions. Keywords: Crawler crane, dynamic, rotation, slewing, torque, swaying, cables, tension, simulation. Figure 1. Virtual model of the crawler crane with key elements