Underhung crane has your material handling under control

22 Sep, 2016

Underhung crane, also called underslung crane or under running overhead crane, which is designed for flexibility and functionality. Because the underhung crane system is usually lighter than top running overhead crane system, so a underhung overhead crane can be hung in the building structure directly without support. Compared with top running overhead crane, underhung crane is more suitable for factory that height is limited.

Underhung crane- Dongqi under running overhead crane

Underhung crane main parameters

Lifting capacity: 1/4-ton to 15-tons;
Lifting span: Under 65 feet;
Crane service: Light to medium duty;
Crane applications: Assembly, fabrication shops, maintenance buildings, and manufacturing facilities;
Supported by existing ceiling trusses or roof structure, the overhead crane can make the most of the floor space of your facility. Reduces costs when the existing support columns can be used;
End hook approach is increased because the bridge beam and hoist are underneath runway beams.

Single girder underhung crane

A single girder underhung crane usually select the under running electric hoist and trolley as the lifting mechanism to moves across the bottom flange of the bridge beam.

Underhung crane - Dongqi under running overhead crane

Single girder underhung crane - Dongqi single girder overhead bridge crane

Double girder underhung cranes

A double girder underhung crane can run its electric hoist and electric trolley along on the top or the bottom of the bridge beams.

Double girder underhung crane - Dongqi double girder overhead crane

Double girder underhung crane - Dongqi double girder overhead bridge crane

Features of Underhung Crane

Ceiling supported runway system for under running cranes will maximize usable floor space
Most commonly used in light to medium duty cycle applications
Can have longer crane spans with 2, 3 or even 4 runway beams to support the under running crane system
Under running cranes are most commonly used in assembly plants, fabrication shops, maintenance areas and manufacturing facilities
The underhung is designed to lift 10 tons or less (some particular overhead crane up to 25 tons available) materials.

Advantages of underhung overhead crane

Easily manipulate even in wide bay, minimizing the depth of bridge beam, and leaving the lighter lifting equipment. Therefore, plenty of space can be saved, as well as lots of capitals will be cut down.
Independent operation that don’t influence the overall or other running.
It can lift or transport materials along with a fixed road, which offer large convenient for production procession.
Maximum use the space of building.
Using the existing ceiling girder to increase the safety of crane track.
Best deal with the situation that headroom is low and maximum the distance from ground to the hook.
All-around guidance on installation and maintenance.
Advanced technology and reasonable design
Profound appearance and strong steel structure
Thoughtful service and competitive price.

Single girder underhung/ underrunning crane v.s Top running single girder crane

An Underhung Crane, or under-running overhead crane rides on the lower flange of the beam, comparing with a top running overhead crane.

On crane i beam & Crane tracking

An Underhung Crane outcomes the top running crane in that the Underhung Crane experiences fewer tracking problems than a top-running crane due to the underhung crane is bolted to the I-beam, which is secured to the building structure. Whereas, it also limits the overhead crane crane’s movement and lessens the chances of rail misalignment.

On realignment

But when an underhung crane system does require realignment, the required downtime may be greater than for a top-running crane system, due to suspension and rigging required for alignment of an underhung system. In contrast, while top-running crane systems require more frequent rail alignment checks and more frequent rail alignment, they are easier service.

Underhung crane： single girder or double girder design?

Underhung cranes is usually designed in single girder configuration for lighter service and lower-capacity lifting applications. When itis designed in double girder, it also can handle loads with higher capacity, but it will be impractical and expensive.

Underhung crane saves your floor space with existing structures

Due to the underhung crane is supported by the existing ceiling trusses or the roof structure, it will helps to maximize the floor space of your facility. Underhung cranes provides excellent side approach and makes the most of your facility’s width and height for being supported by roof or ceiling structures. Underhung crane is the first choice for facilities with limited vertical clearance or headroom to install a top-running overhead crane system.

Free standing designs for factory with no exsting structrues

Underhung cranes also can be used in the facility without existing supporting structures which can support the crane runway. In the condition, it will be designed in a free-standing configuration with the support or mounting columns.

On lifting height of underhung crane

Compared with the top running overhead crane, the underhung crane has less hook height and lift height due to the bridge and electric hoist hang underneath the runways.

Installation of underhung cranes

As for installation and service of an underhung crane system, the procedure can be complex and may cause to longer downtime. Because the underhung crane is suspended from the runways, longer time will be taken to check the alignment or service the wheels of the overhead crane, but it is easier to maintain the alignment and cause fewer tracking problems because the I-beam design is secured to building structure—limiting movement

When buying an underhung crane

When buy an underhung overhead crane, the following should be considered:
Is your building’s structure strong enough to support a crane system? If not, a freestanding overhead crane system is an option. The drawback of a freestanding underhung crane system is that it takes up floor space from production and other uses.

Generally, the under running overhead crane flexibility, functionality, and ergonomic solutions, whereas, the top running overhead crane kits is featured of higher capacity lifts and higher lift heights and more overhead room.If you are in need of an overhead crane, and do not how to select from the top running system or under running system, please leave a message below.