Mulholland Engineering Ltd

Global Track pivotal manual bridge cranes

A conventional bridge, or gantry crane, relies on long end carriages and a rigid connection
between end carriage and the bridge to keep the bridge at 90° to the runway beams(when
viewed from above), at all times. If the bridge is at less than 90° from the runway beams, it is
known as “crabbing”, and it leads to increased side loads on the end carriage wheels,
increased effort required to move the bridge along the runway beams and increased wear on
the end carriage wheels and the runway beams.

The revolutionary Global Track pivotal manual bridge crane sidesteps the whole problem of
crabbing. The bridge has a pivoted connection to each end carriage so that it can be at less
than 90° to the runway beams. Clearly, the distance between the two end carriages increases
if the bridge is not at 90°, but the Global Track design allows for this by suspending the bridge
from the end carriages via swinging U-hangers. As the angle between the bridge and the
runway beams reduces, the U-hangers swing inboard to provide the extra length.

The advantages of the Global Track pivotal manual bridge crane compared with conventional
cranes are:
shorter end carriages so the crane can get closer to the ends of the runway beams;
reduced wear on end carriages and runway beams;
reduced effort to move the bridge along the runway beams;
the length of the bridge can be increased. Global Track manufactures a manual pivotal 15
metre bridge – a world first.
For more information follow the link to www.globaltrack.com.au