Double Box Girders Done Right
Double box girders have some real muscle. One of their major advantages? They can be shipped with end trucks pre-assembled. That’s less on-site labor, less setup time, and less hassle. Your crew will appreciate that.
And if you’re dealing with heavy-duty cycles or using a magnet as a below-the-hook device, double girders are almost always the right call. Just let us know upfront—magnet cranes take a beating and usually need to be built to CMAA Class D or higher.
8 Wheels. Double the Control.
In some situations, a four-wheel setup just won’t cut it. That’s where double bogie cranes come into play. These systems use eight wheels—four per side—to better distribute the load. This lets us dial down the rail size and, in some cases, even trim weight from the runway girders. That’s smart crane design in action.
Top Running Box Girders: Height without the Hassle
When hook height matters (and let’s be honest—it usually does), box girders deliver. Since the hoist and trolley ride on top of the bridge, not underneath, you gain maximum lift distance. This setup allows you to design lower buildings without giving up performance—a major win in new construction.
Pair these girders with electric wire rope hoists and you’ve got a solid, top-running system that’s built for reliability, speed, and long service life. Got a unique need? We’ve custom-fit electric chain hoists on box girders, too.
Mono Box Girders: Single, Strong, and Efficient
Even motorized, top-running single girders benefit from box girder construction when spans exceed 60–65 feet. These are often called mono box bridge cranes, and they pack the same light-to-span advantage as their double girder cousins.
Key benefits include:
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Longer wheel and bearing life than underhung systems
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High speeds—up to 200 FPM
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Excellent headroom
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Preassembled shipping options
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Remote and pendant control options for safety
