Design of lifting mechanism for large lifting height of outdoor gantry crane

At present, the lifting height of conventionally produced outdoor gantry cranes is generally 12-20 meters. In actual use, users often put forward higher lifting height requirements. There are several common solutions to solve the problem of large lifting height of outdoor gantry cranes.

First, you can increase the diameter or length of the outdoor gantry crane for sale drum. This solution is simple and easy to implement, but excessively increasing the diameter of the drum will increase the height of the hoisting mechanism, and excessively increasing the length of the drum will increase the deflection angle of the wire rope to the pulley and drum rope groove, aggravating wear and even It will cause damage to the pulley groove or jump of the wire rope. This solution has great limitations. Secondly, reduce the pulley group magnification. This solution is also simple and easy to implement. Appropriately reducing the pulley group magnification can reduce the amount of wire rope winding on the drum without increasing the overall size of the mechanism. It is more suitable in situations where there are restrictions on the overall size of the lifting mechanism. suitable. However, the force on the drum increases, the diameter of the wire rope increases, and the transmission ratio of the reducer also increases, which has certain limitations in use.

The steel wire rope of industrial outdoor gantry crane is double-layered. The end of the wire rope is fixed in the middle of the free double-layer winding of the drum. The wire rope is wound to both ends along the spiral groove of the drum. When the winding reaches the end of the wall, it enters the second layer of winding. The horizontal component force generated by the deflection angle of the wire rope and the guiding effect of the adjacent rope loops make it wind to the middle of the drum, and its spiral direction is opposite to that of the first layer. This winding method has a simple structure and does not require a guide rope device. However, the deflection angle of the wire rope cannot be too large, otherwise the second layer of wire ropes will not be easily arranged neatly. This method is only used for cranes that do not work frequently. Double-layer winding is used, and both ends of the drum should be equipped with retaining rings to limit the overflow of the wire rope and a guide rope mechanism to guide the wire rope to the second layer. Since the winding spiral direction of the second layer is exactly opposite to that of the first layer, the bottom wire rope cannot guide the arrangement of the upper wire rope very well, and the second layer of wire rope may not be tightly arranged. Therefore, the design must ensure that there are enough free turns in the middle of the drum when it is lifted to the upper limit position. In double-drum winding, one motor drives two reducers at the same time, driving two sets of drums to perform winding motion at the same time, which can double the lifting height. The disadvantage is that the number of accessories increases and the overall size of the mechanism is larger.

Regarding the design of the drum of an electric automated outdoor gantry crane cost with a large lifting height, the design of the drum with a large lifting height should generally be selected based on the different use occasions and working levels of the gantry crane and the specific usage conditions. You can also combine the advantages of the above solutions to form a set of specific solutions without being limited to using only one solution.