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Cranes, Manipulators & Machinery Manufacturer in the United States


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Telescoping Bridge Crane

Telescoping Bridge Crane

In certain scenarios, the project engineer might identify a bridge crane as the ideal solution for a material-handling challenge, except when the bridge (the moving rail in a bridge-and-runway crane) needs to extend into a neighboring zone and then retract. This is where a telescoping bridge crane would be optimal.

For instance, consider this scenario: in the image, the bridge extends beyond the crane to reach a point in a robot cell. However, it must retract from the robot cell to prevent collision when the robot operates. In such cases where there is no runway, this setup is termed a telescoping monorail.

Several reasons exist for extending a bridge into an area and retracting it: allowing passage for another crane, facilitating transfers, ensuring food-grade bin openings when there’s no hoist overhead, and more.

In the accompanying photo, a ‘ski-bar’ triggers a limit switch, confirming the withdrawal of the bridge from the robot cell. This action enables the robot to commence its operations.

The G-Rail™ Advantage for Telescoping Monorail

One of the primary challenges for designers is ensuring that the trolleys supporting the telescoping bridge handle the load distribution appropriately, particularly when dealing with cantilevered loads. In this scenario, the leading trolley experiences an exaggerated load, often surpassing the hoist’s load, while the trailing trolley encounters an upward force.

Notably, not all trolleys are equipped to handle upward loads, but our G-Rail™ trolleys are specifically designed to withstand both downward and upward loads. Additionally, the header, or in the more common setup, the runway, must bear an unusually high load in such cases.

Another crucial consideration involves the constant impact of the telescoping bridge against its stops, or ‘softstops.’ Despite operator care, the fast-paced production setting leads to routine collisions. If these stops are made of durable, harder materials, the impact can transfer to the bridge, runways, or the frame. Utilizing softer materials or hydraulic shock absorbers is advisable to minimize these impacts.

Watch the telescoping bridge in action here

Have any questions about our telescoping monorail?