What are the differences between bridge cranes type single beam and double beam?

1 November, 2025 1 category 10:33 am

At the top of industrial plants, bridge cranes are the most common and core material handling equipment. When you need to choose a suitable crane for its application, the first basic question you face is: Should it be a single beam or a double beam?

This choice is not simply about comparing prices, but a comprehensive consideration of equipment performance, workshop conditions, usage requirements, and long-term costs. This article will delve into the core differences between bridge single beam and double beam cranes, helping you make the wisest decisions.

1. Structure and appearance

As the name suggests, the fundamental difference between the two lies in the number of main beams.

Single beam bridge cranes

There is only one main beam (usually a box beam or composite beam), and a crane trolley (usually an electric hoist) runs on the track below the main beam.

Appearance: The structure is relatively simple, and overall it looks lighter.

Double beam bridge cranes

Having two parallel main beams, the crane trolley (usually a winch type trolley) runs on the track between the two main beams.

Appearance: The structure is more stable, and the overall appearance is thicker and stronger.

2. Comparison of core differences

To demonstrate the differences more clearly, we will compare from the following key dimensions:

Aspect	Single-Girder Overhead Crane	Double-Girder Overhead Crane	Key Takeaway
1. Lifting Capacity	Relatively small, typically from 0.5 to 20 tons.	Wider range, from 5 tons to several hundred tons and beyond.	The double-girder design distributes the load, making it inherently stronger and more stable for larger capacities. It’s the only choice for heavy loads.
2. Duty Cycle & Frequency	Suitable for Class A3 and below. Ideal for light to moderate service, not for intense, frequent operation.	Can easily achieve Class A5, A6, or higher. Designed for heavy-duty, high-frequency cycles.	The mechanical structure of a double-girder crane (especially the hoist and trolley) is more robust and durable for continuous, demanding work.
3. Span & Stability	Can experience more beam deflection (sagging) under load, especially with larger spans (e.g., >20m), affecting smooth operation.	Excellent rigidity. Maintains superior stability with minimal deflection, even over large spans.	The double-girder structure acts as a rigid portal frame, offering far greater resistance to deformation. Essential for large workshops requiring stability.
4. Hook Lift Height	Greater effective hook height. The hoist runs under the girder, consuming less headroom.	Slightly less hook height. The trolley runs between the girders, which adds to the crane’s own height.	In a building with a fixed ceiling height, a single-girder crane provides more usable lifting height, a key advantage in space-constrained facilities.
5. Cost Considerations	Lower initial investment. Simpler structure leads to lower manufacturing and installation costs.	Higher initial investment. More complex structure, more materials, and higher installation requirements.	Single-girder cranes have a clear price advantage. However, for heavy-duty use, the double-girder’s longer lifespan and reliability may offer better long-term value.
6. Maintenance & Expandability	Maintenance is simpler, but the design offers limited options for expansion or upgrades.	More maintenance points, but features better modularity and greater expandability. Advanced features like automation, anti-sway, and precision positioning can be more readily added.	The double-girder crane is a better foundation for automated and smart material handling systems, making it a more future-proof investment.

3. How to choose?

Priority should be given to selecting a single beam bridge cranes:

The lifting capacity requirement is not high: usually below 20 tons.
Not frequently used: used several times a day or intermittently, not for 24-hour continuous operation.
Limited budget: sensitive to initial investment costs.
The clearance height of the factory building is limited: the highest possible lifting height is required.
Application scenarios: light to moderate operating environments such as machining workshops, assembly workshops, warehouses, and maintenance rooms.

Priority should be given to selecting double beam bridge cranes:

Large lifting capacity requirements: typically heavy loads exceeding 20 tons.
High intensity and high-frequency use: working conditions that require 7×24 hours of continuous operation, such as metallurgy, casting, and material handling centers.
Large span, requiring smooth operation: Large span, and high requirements for lifting stability and precise positioning (such as precision equipment installation).
High security and reliability are required: involving valuable products or high-risk operations.
In the future, there will be a need for automation upgrades: plans are being made to integrate it into automated production lines.

Summary

Simply put, choosing between single beam or double beam is a process of finding the optimal balance between cost, performance, and demand.

A single beam crane is like an economical and practical “family sedan”, more than enough to meet daily commuting (light to moderate operations), and has low purchasing and maintenance costs.

Double beam cranes are like sturdy and durable “heavy-duty trucks” or “special operation vehicles”, designed to undertake extreme tasks (heavy loads, high frequencies). Although they are expensive, they are irreplaceable in their applicable fields.

Ultimately, your specific needs, including maximum lifting capacity, work intensity, workshop conditions, and long-term planning, will directly determine the most suitable type of crane for you. It is recommended to have detailed communication with professional crane engineers or suppliers before procurement to ensure maximum return on your investment.