A Guide to Double Girder Overhead Cranes!

When using a double girder overhead crane design, the crane travels overhead on two girder beams that are supported by end trucks or end carriages on either side. The hoist trolley or open winch trolley of a double girder crane is often configured in a top-running crane arrangement, where it runs on a rail or track that is placed on top of the overhead girders. 

When the hoist is positioned between or on top of the cross girders in a double beam configuration, the double girder bridge cranes aid in determining the cross girder's depth. Double girder overhead cranes are often advised for heavy-duty material handling with greater lifting capacity and longer spans. 

As a result, the hoist trolley and open winch trolley, among other crane parts and components, are more intricately designed in the double girder overhead crane system, making them more costly than single-girder overhead cranes.

What is a Double Girder Overhead Crane?

An overhead crane with two beams rather than one is called a double-girder overhead crane, double-girder bridge crane, or double-girder EOT crane. Medium and heavy-duty weights are lifted with a twin girder overhead crane. They use two adjacently positioned beams to move larger capacity loads and give better support for the products being carried.

Due to its employment in heavy-duty applications, twin girder cranes often have more sophisticated components, which raises their price. Two bridge girders, two end trucks, and a trolley hoist assembly comprise a double girder overhead bridge crane setup.

Top-running end trucks are more frequently used in double girder bridge cranes, however, they are not the only ones. In some limited headroom situations, under-running end trucks can also be employed.

Double Girder Overhead Crane Advantages

Capacity

The primary justification for employing a single or double girder crane is frequent load capacity. A twin girder bridge crane is an economical and space-efficient option if you need to lift loads of more than 15 tons on a continuous duty cycle. 

Increased Hook Height

The hoist and trolley of a double girder bridge crane move atop the bridge, raising the hook height. Compared to a single girder crane with an underhanging trolley and hoist, this allows operators to lift longer and higher objects and materials inside a work area. 

Cover Greater Distances

Due to the parallel girder design's higher combined strength than a single girder, a double girder bridge crane can also cover greater distances.

Types of Double Girder Overhead Cranes!

The most popular kind of overhead crane is the two-girder kind. It may be divided into two categories according to the kind of trolley: winch and hoist. Double girder cranes come in two varieties: the LH type for hoist trolleys and the QD type for winch trolleys.

Double Girder Overhead Cranes for a Range of Industrial Situations!

Two types of hoist trolley double girder bridge cranes that can fulfill hook lifting needs under most working situations are the winch trolley double girder cranes. Additionally, overhead cranes may be outfitted with various lifting apparatuses and trolley designs which make them appropriate for specialized applications across many sectors. These are a few unique situations that pertain to the prefabrication and metallurgical sectors.

Which One to Choose: Single or double girder overhead crane?

The idea that double-girder cranes are superior to single-girder cranes in terms of quality and durability is a prevalent misunderstanding regarding overhead cranes. Both kinds of overhead cranes are equally durable and of the same high quality. Single-girder cranes can have a lot of advantages over double-girder cranes."

For facilities with limited headroom and floor space, a single-girder crane is an ideal option since it is lighter and more compact than a double girder overhead crane. A single-girder crane can have a superior end approach to the structure, allowing the hook to move closer to the wall, even when things need to be lifted and moved near the building walls. Because there is less deadweight applied to the building foundations when there is only one girder, building designs, and runway construction can be more economically viable. Additionally, the girder requires less steel to fabricate, making it a cost-effective lifting option for a variety of industries and applications.

However, a single-girder crane might not be the best option in every situation. A double girder overhead crane could be a preferable choice if a service platform, a larger lifting capacity, or a higher lift height are required. To provide the appropriate lifting equipment for the site, it is usually crucial to comprehend the specifications of the lifting work and the climate in which the crane is intended to function.

Conclusion

So, do you require a single or double girder overhead crane? The answer depends on several factors, as usual. You must take into account the maximum span, capacity, and headroom to choose the best option for your application.

Although both single-girder and double-girder cranes are robust and long-lasting, their lift and height capacities differ. A possible 18 to 36 inches are taken out of the vertical lifting capability of single girder cranes since the hoist hook is placed below the girder with the assembly hooked to the bottom. However, twin girder cranes have a better lift capacity for larger weights since the hoist assembly is mounted along the top of the girders and the hoist is in the same plane as the girders.

Frequently Asked Questions

What distinguishes single-girder cranes from double-girder cranes? 

The lifting height and load capacity of single-girder and double-girder cranes are the primary distinctions between them. Double girder overhead cranes can lift higher and support bigger loads than single-girder.

Are cranes with two girders necessarily superior to those with one? 

Not always. Many variables, including the required load capacity, lifting height, available space, and budget, influence the decision between single-girder and double-girder cranes.

Single-girder or double girder overhead cranes: which one requires less maintenance? 

Single-girder cranes often require less maintenance because they have fewer parts and a simpler design.