Design Of Low-height On Overhead Travelling Crane Trolley

General overhead traveling crane is used in our company’s steelworks.In production process, the crane was mainly used for hoisting the slag pot filled with liquid slag that in molten state. So, the higher requirement in crane security was put forward.In the original production process, the slag pot weights14t,its volume is6m3, the specific gravity of liquid slag produced by BOF steelmaking is4t/m3,the spreader weight3t,the total weight is41t.So, the50/30t crane can complete the hoisting and tipping of the slag pot. However, as the production process has changed, the liquid slag was processed by slag processing plant. The slag pot was only hoisted, not tipped by the crane. At the same time, the volume of the slag pot was expanded, the new pot’s volume is8m3,it weights15t,,the spreader weight4t. So, the50/30t crane will be in full load condition, thus the crane whose lifting capacity is54t is necessary.The conditions of the plant can’t meet the installation requirements of new crane, So transforming the original crane is the only program to guarantee that the crane lifting capacity is enough. In the transformation process, the1st step is to analyze the working conditions and field conditions, redefine the performance level of the crane. Next step is to design the hoisting mechanism, operating agencies, the trolley frame, in order to reduce the total height of the trolley. The3rd step is to analyze the force condition of trolley through finite element method, ensure the structural strength can be meet, reduce the weight and height of the trolley.In the transformation process, reliability is the center. The rehabilitation programs make the trolley become more reasonable,more secure in the structure, more convenient in maintenance and stronger adaptability. So, this process makes the improvement of the equipment in old workshops become possible.