underhung overhead crane
Underhung bridge crane, also called under slung bridge crane or under running bridge crane, is designed for flexibility and functionality, which provides an ergonomic design that offers versatility and usability. Generally, underhung bridge crane is available for lighter capacity usually no more than 10t.
The structure of underhung bridge crane is that the end trucks lies on the bottom flange of the runway beam, and the runway beam is usually suspended from the roof, which can eliminate the requires of extra floor columns to support the runway. The reason why this structure is the under hung crane system is that it is much lighter than the top-running system. Underhung cranes can be either single girder or double girder. Double girder underhung cranes are often suitable for longer span or higher capacities.
- Lifting capacity:0.5-10t
- Ambient temperature:-20—+40℃
Advantages of underhung bridge crane
- A long underhung crane can be easily operated, even in very wide bays with multiple runways to minimize the depth of bridge girder and decrease the weight of the operating equipments which can lower the costs and lighter design requirements.
- Without interfering with one another or the overall operation, the underhung crane can be operated side-by-side. In the situation of wide bays, we can install multiple underhung crane runways adjacent to one another and simultaneously operate. What's more, they can pass each other on independent runways.
- The use of interlock mechanisms and switches is another benefit of installing underhung crane systems. Interlocks are mechanical devices that lock the adjacent ends of two cranes together to enable the transfer of carriers from one crane or track to another. Using an interlock device to connect two crane systems is much easier and more cost effective than purchasing and installing one massive system. It is ideal to use underhung ceiling-mounted monorail and bridge crane systems for production processes which require lifting and transporting materials along a fixed path.
Comparison of top-running crane and underhung crane
- Compared to top-running crane, the primary advantage of underhung, or under-running crane is it typically experiences fewer tracking problems than a top-running crane. The reason is that underhung crane is bolted to the I-beam to secure the building structure which limits the crane’s movement and lessens the chances of rail misalignment.
- Underhung crane is not always good you should choose the most proper crane according to your requirements. For example, when underhung system requires realignment, the required downtime is greater than for a top-running system. In contrast, while top-running systems require more frequent rail alignment or alignment checks, it is easy to realize.
- About choosing top-running crane or underhung crane, another thing you should consider is that if your building’s structure strong enough to support a crane system, if not, underhung crane is a better choice.