Bridge cranes are widely used in metalworking workshops, assembly workshops, metal structure workshops, maintenance workshops, various types of warehouses, and other occasions. They can also be used for auxiliary lifting in metallurgical and foundry workshops.
The main girder of a bridge crane is an elastic structure that deforms under load. When the load is removed, the deformation disappears and the main girder can return to its original state. To prevent the trolley from climbing, which increases running resistance and causes structural vibration, the upward camber can compensate and eliminate the downward deflection of the main girder. Generally, when the span of the main girder exceeds 13.5 meters, it is made with an upward camber. The distance from the horizontal line on the upper surface of the main girder to the apex of the camber curve at mid-span is called the upward camber.
Through years of production practice, it has been found that during the assembly of the bridge structure of a bridge crane, the self-weight of the main girder inevitably causes downward deflection. Due to different support positions, the downward deflection caused by the self-weight of the main girder varies, and thus the measured upward camber values also differ. Only when the supports are placed directly under the centerline of the span at both ends of the bridge structure is the measured upward camber accurate and does not require correction. In the bridge structure diagram with supports placed on the broken beam, during actual assembly, according to the assembly and welding process requirements of the main girder and end girders, to facilitate the insertion of the main girder into the end girders, the two supports are often placed on the main girder.
In bridge cranes, the service life of the main girder directly affects the lifespan of the crane. To reduce the weight of the bridge crane, it is necessary to optimize the design of the main girder structure. By optimizing the main girder structure, the self-weight and height of the crane can be effectively reduced, and the maintenance cost of the bridge erecting machine can be lowered. Through optimized design of the main girder, the crane can be made lighter, more compact, and simpler. Return to Sohu to view more.
