When Cutting Crane Girder Is Necessary ?＞20 M Large Span Crane
When Cutting the Crane Main Girder Is Commonly Seen: In-Depth Explanation
Transportation Limitations
Why It Matters: Most countries restrict overland transport of oversized components. In general, the maximum legal transport length without special permits is around 12 meters (or 40 feet). If a crane girder exceeds this length, it cannot be shipped as a single piece by standard road or sea transport methods.
When Girder Cutting Is Required:
- Cranes with spans over 20 meters almost always require the main girder to be split into two or more segments.
- For exported overhead cranes, especially for overseas markets, containerized transport is preferred for cost, safety, and efficiency.
- Girder sections are designed to fit within ISO shipping containers (20ft, 40ft HQ) or flat racks.
- Splitting the girder also reduces the risk of damage during long-distance transport.
Example: A 25-meter-span double girder bridge crane for a steel plant in the Middle East must be divided into two 12.5-meter sections to fit into 40-foot flat-rack containers for ocean shipping.
Workshop or Site Access Constraints
Why It Matters: Some installation sites have narrow doorways, limited turning radius, or low ceiling clearance. Trying to move a 20+ meter girder into such a space in one piece is often impossible or unsafe.
When Girder Cutting Is Used:
- Common in brownfield projects, where an existing plant is being upgraded with a new overhead bridge crane.
- Also seen in urban environments, where crane components must pass through restricted entryways or building floors.
- Cutting the girder into manageable segments (e.g., 2 × 10 meters) makes it easier to bring inside with forklifts or small hoists.
- Assembly is done inside the building using manual alignment tools or small lifting gear.
Example: A food processing factory in a city center requires a 16-meter overhead crane but only has a 3-meter wide side entry gate. The girder is cut into 8-meter sections to pass through and assembled inside the building.
The sections of main girders assembled or connected at installation site which can ensure safety and durability
Very Large Span Cranes
Why It Matters: When crane spans exceed 25–30 meters, manufacturing, transporting, and installing a one-piece girder becomes impractical, uneconomical, and structurally risky.
When Girder Cutting Is Standard:
- For container gantry cranes, RTGs, large double girder bridge cranes, the girder is always segmented.
- Girders are often split into 3 segments: left, center, right to ensure balanced load distribution and ease of transport.
- A flange-type splice joint or internal box splice is used to maintain strength and stiffness at connection points.
Engineering Considerations:
- Splice locations are chosen at low-moment zones to reduce stress.
- Connection design must follow FEM, DIN, or CMAA standards for fatigue and structural integrity.
Example: A 35-meter-span double girder bridge crane for a turbine factory is manufactured in three parts (12m + 11m + 12m), then joined on-site using flange plates and alignment dowels.
Modular Production or Stocking Strategy
Why It Matters: For crane manufacturers serving global clients or high-demand projects, using modular girder segments simplifies logistics and reduces lead time. It also enables faster customization.
When Girder Cutting Is Strategic (Not Just Necessary):
- Modular segments can be pre-stocked and assembled based on final order specs.
- Suppliers use standardized flange joints, making each connection predictable and easy to inspect.
- Useful in crane kit solutions, where clients fabricate girders locally and receive the main segments for splicing.
Example: A Chinese crane supplier provides 20-meter modular double girder kits in two 10-meter segments, allowing dealers or installers to store and combine girders flexibly depending on end-user needs.
Typical Scenarios Where Main Girder Cutting Is Seen
| Crane Type | Span Example | Girders Cut? | Reason | |
|---|---|---|---|---|
| 10-ton single girder | < 15m | Rarely | Usually within legal road transport limit | |
| 20-ton double girder | 20–30m | Common | Spans too long for one-piece transport | |
| 30-ton container gantry | > 30m | Very common | Large spans always require segmentation | |
| Exported EOT crane | > 12m span | Very common | Needs to fit containers or flat racks | |
| Factory with tight access | > 10m | Occasionally | Access issues make smaller segments easier | 5 |
Conclusion: Girder Cutting Is a Smart and Safe Practice
Cutting the crane main girder into segments is not only common—it’s often the only practical solution in modern overhead crane manufacturing and installation.
When done correctly:
- With engineered flange joints,
- Precision alignment and torquing procedures,
- And following relevant safety standards,
a split girder performs just as reliably as a single-piece girder.
It’s a proven practice in export projects, large-span bridge cranes, modular production, and complex installation environments.
Related: Crane Girder Designs:Single vs Double Girder, Beam & Box Girder
Article by Bella ，who has been in the hoist and crane field since 2016. Bella provides overhead crane & gantry crane consultation services for clients who need a customized overhead travelling crane solution.Contact her to get free consultation.