Operating skills for operating overhead cranes to flip objects in the air

In the production operation, due to the requirements of a certain production process, a certain object needs to be turned 90 degrees or 180 degrees in the air in order to complete a certain process. In this case, a crane with two sets of main and auxiliary lifting mechanisms is usually used to realize this process.

1. How to turn the object 90 degrees with overhead cranes

The turning of the ladle is an example of the object turning 90 degrees. The operation method is: use a crane with two sets of main and auxiliary lifting mechanisms to complete the task of turning the ladle. Generally, the main hook is hung on the upper lifting point of the overturned object, such as the ladle, to carry the lifting of the ladle. The auxiliary hook is hung on the lower hanging point to make the ladle tip over. as the picture shows.

When lifting, the two hooks are simultaneously lifted and the large and small carts are driven to transport the ladle to the casting position. During casting, the two hooks are lowered at the same time. When the ladle is lowered to a suitable height for casting, the auxiliary hook is slowly raised to make the bottom of the ladle rise gradually. At the same time, the main hook continues to descend and adjust the position of the trolley to ensure While the ladle is turned over, the pouring nozzle of the ladle should always be aligned with the pouring nozzle, and the poured molten steel should be accurately injected into the gate. Pour the molten steel to prevent the molten steel from damaging the sand mold.

2. How to turn the object 180 degrees with overhead cranes

In many cases, such as process installation, machine parts processing or equipment overhaul, the workpiece needs to be turned 180 degrees. The operation method is shown in the figure. Use two sets of longer slings. Same as point B in wall chart a. After the sling 1 goes around the bottom of the object, it is tied to the main hook, and the sling is directly tied to the secondary hook. After the hooks are properly hung, the two hooks are lifted at the same time, so that the object is about 0.3 to 0.5 meters away from the ground, and then the auxiliary hook is stopped and the main hook continues to be lifted. At this time, the work will gradually turn upwards around the B end in the air. In order to keep point B at a distance of 0.3 to 0.5 meters from the ground, while the main hook is gradually raised, continue to land the secondary hook. Under such slow and steady coordinated movements of the main and auxiliary hooks, the work can be turned 90 degrees. As shown in Figure b. When the object is turned over 900. The auxiliary hook continues to descend slowly, and the main hook continues to rise to prevent the work from touching the ground. After this continuous action. The upper part of the work rests on the sling of the auxiliary hook. With the decline of the secondary hook. Working end A rotates clockwise around end B. Turn the workpiece safely by 180 degrees.

Schematic diagram of an object flipping in the air

a) Lift the main hook b) Turn 90 degrees c) Turn 180 degrees

When operating the crane to turn objects, it is best to be operated by experienced operators to prevent accidents.