30m box girder to use how much gantry crane?
As for the crane is not recommended, because the crane is very expensive, and not suitable for lifting the prefabricated beam
But recommend you use two sets of 60 tons, because a span of 30m above 120 tons gantry crane than two spans of more than 10 meters 30 tons of expensive
You can use a 120 tons of box gantry crane, you can also use two sets of 60 tons of gantry crane
