A bridge crane system—otherwise known as an overhead crane or overhead bridge crane—is typically mounted inside of the building in which it operates. The frame is fixed to the building structure using beams and a moving bridge spans them. In cases where the building cannot support the crane, a standalone structure is built to support it. This is called a “freestanding” overhead crane because it doesn’t rely on support from the building and can be placed anywhere, including outside. Whether freestanding or supported by the building structure, a bridge crane system is fixed in place where it is installed.
In comparison, a gantry crane is typically not mounted to the building structure. Instead of being fixed in place, it sits on caster wheels or a floor track which give it flexibility to be used across multiple applications in a production space. A typical A-frame construction supports the overhead beam.
These two crane types vary in their lifting capacity mainly due to their construction. As you might expect, with the bridge crane system being fixed in place, it has a generally higher lifting limit (up to 100 tons). Gantry cranes are not as capable, but typically lift loads of up to 15 tons.
That’s not to say a gantry crane cannot be designed and built that lifts much more!
Another big difference is that a gantry crane doesn’t have a runway because it rolls on wheels or a track. This keeps the overhead area clear of a runway and eliminates supporting columns which depending on the application may be an important factor to consider.
They also differ in their purpose. Gantry cranes are generally used to service a small or specific area and function. Bridge cranes can be used to serve a large area where multiple processes are being performed, like an assembly line.
The use of a gantry crane specifically over an overhead crane is due to shipyards being huge spaces that benefit by not having support columns in the way. A gantry crane is self-supporting and the use of rails at ground level enables the free movement of vehicles and people maximizing the use of space –something especially important when working on this scale.
Post time: Sep-22-2022