Underhung crane
Underhung crane
An underhung crane, also known as an under-running crane, is a type of overhead crane where the bridge (the horizontal beam carrying the hoist and trolley) runs on the bottom flange of runway beams, rather than on top as in traditional overhead bridge cranes. Here are the key features and characteristics of underhung cranes:
- Structure:
- Bridge: The horizontal beam that carries the hoist and trolley mechanism.
- Runway beams: Typically I-beams or enclosed tracks that are mounted on the ceiling or overhead structure.
- End trucks: These support the bridge and contain the wheels or rollers that move along the runway beams.
- Design and Operation:
- The bridge of an underhung crane is suspended from the runway beams using hangers or suspension brackets.
- The wheels or rollers on the end trucks of the bridge travel along the lower flange of the runway beams.
- Underhung cranes are designed to maximize headroom and floor space utilization, making them suitable for facilities with limited overhead clearance or where the floor area needs to remain clear.
- Advantages:
- Space-saving: Underhung cranes utilize the space above without occupying floor space, making them ideal for applications where floor space is valuable.
- Precise positioning: They offer precise control and positioning of loads due to their smooth travel along the runway beams.
- Versatility: Underhung cranes can be installed in various configurations, such as straight line, curved track, or even as part of a monorail system.
- Applications:
- Workstations: Used in assembly lines and workstations where frequent and precise material handling is required.
- Storage and retrieval: Effective in warehouses and distribution centers for moving goods between storage locations.
- Light to medium lifting: Suitable for tasks that require lifting capacities ranging from light to moderate weights.
- Considerations:
- Load capacity: Underhung cranes are typically designed for lighter to medium lifting capacities compared to larger overhead bridge cranes.
- Runway installation: Proper installation of the runway beams is critical to ensure smooth operation and load stability.
- Maintenance: Accessibility to the runway beams and proper maintenance of the wheels or rollers are important for crane performance and longevity.
Underhung cranes offer a flexible and efficient solution for material handling in various industrial and commercial environments, providing precise control and maximizing usable space. The choice of an underhung crane depends on factors such as load requirements, available space, and operational needs.