What is the difference between single girder and double girder crane?

Bridge cranes can be divided into single-girder and double-girder bridge cranes according to their categories. In addition to the difference between the single-girder and double-girder that people generally know, what are the specific differences between the single-girder bridge crane and the double-girder bridge crane?

The structural difference between single girder crane and double girder crane
Generally, the structure of the top running bridge crane is relatively simple, its own weight is light, and it is relatively simple in installation, daily maintenance, assembly and disassembly. However, the structure of the double-girder bridge crane is relatively complex, its own weight is large, and the installation, daily maintenance and repair are relatively complicated.

The monorail overhead crane itself is light in weight, relatively simple in structure, and relatively simple to install, dismantle, and maintain, while the double-girder overhead crane itself is relatively heavy in weight, more complicated in structure, and has higher requirements for assembly, disassembly, and maintenance.

The difference between the manufacturing cost of single girder crane and double girder crane
Underhung cranes are shorter in span and relatively smaller in fuselage, so they consume less construction material and are less expensive. The double-girder bridge crane has a larger span, larger body, more consumables, and higher technical content, so the production cost is higher.

Differences between single-girder cranes and double-girder cranes
In terms of operation mode, single-girder cranes are generally operated on the ground, and can be operated by handle and remote control, while double-girder bridge cranes require workers to control them during operation.

The difference between the mechanical properties of single girder cranes and double girder cranes
In terms of mechanical properties, the stability of the top running crane is relatively low, the rated lifting capacity is relatively small, and the level of work is relatively low. The double-girder bridge crane has relatively high stability, heavy rated lifting capacity, and relatively high working level.
The single-girder bridge crane has a small rated lifting capacity, a relatively low working level, and low stability, while the double-girder crane has a large rated lifting capacity, a higher working level, and relatively better stability.

The difference between single girder crane and double girder crane operating environment
Generally, electric overhead traveling cranes are suitable for work sites with short spans, relatively light lifting weights, and relatively small construction site space. The double-girder bridge crane is suitable for sites with long spans, relatively heavy lifting capacity, and wide construction site space.
Single-girder bridge cranes are often used in places with short spans, low lifting capacity and small working space. The double-girder bridge crane is used in places with large spans, relatively large lifting weights, and large working spaces. Comparing the two, the working level of the double girder bridge crane is higher.