Portal cranes are available in two main configurations: single girder and double girder systems. The key difference lies in the support structure, where single girder portal cranes use one main beam and double girder portal cranes have two parallel beams. These construction differences determine the lifting capacity, span, and application possibilities of both crane types.
What are the main technical differences between single girder and double girder portal cranes?
Single girder portal cranes have one main beam on which the crane runs, while double girder portal cranes use two parallel beams. These construction differences directly influence the lifting capacity, stability, and span of the crane system.
The support structure forms the fundamental distinction. In single girder systems, the load hangs on one side of the main beam, resulting in asymmetric loading. This requires a more robust construction of the beam itself to handle tilting moments. Double girder portal cranes distribute the load across two beams, creating symmetric loading and enabling higher lifting capacities.
Technical specifications differ significantly between both types:
- Stability: Double girder systems offer inherently more stability through the wider base
- Hook height: Single girder cranes often have limited hook height due to construction constraints
- Trolley movement: Double girder cranes can move across the full span, single girder cranes have overhang
- Wind sensitivity: Single girder systems are more sensitive to lateral wind forces
What lifting capacity and span are possible with single girder versus double girder portal cranes?
Single girder portal cranes typically achieve lifting capacities up to 20 tons with spans up to 30 meters. Double girder portal cranes can realize lifting capacities up to 250 tons with spans up to 60 meters, depending on the specific construction and foundation.
The practical limits are determined by various factors. Single girder portal cranes are ideal for lighter applications in production environments, assembly lines, and smaller storage facilities. The limited lifting capacity is compensated by lower costs and simpler installation.
Double girder portal cranes dominate in heavy industrial applications:
- Steel industry: Lifting heavy plates and profiles up to 100+ tons
- Shipbuilding: Manipulation of large ship components
- Energy sector: Installation of transformers and turbine components
- Container terminals: Stacking and transport of containers
Mobile portal cranes and semi-portal cranes offer flexibility within these capacity ranges, with mobile systems particularly suitable for temporary projects and semi-portal cranes saving space by using existing building structures.
When do you choose a single girder and when a double girder portal crane?
Choose single girder portal cranes for lifting capacities under 20 tons, limited space, and cost-conscious projects. Double girder portal cranes are necessary for heavier loads, large spans, and intensive use in industrial environments.
The decision criteria include multiple practical considerations. Spatial constraints play a crucial role, as single girder systems take up less space and are suitable for tight production environments. Double girder cranes require more free space but offer superior performance for heavy applications.
Operational requirements often determine the choice:
- Usage frequency: Intensive use justifies investment in double girder systems
- Precision requirements: Double girder cranes offer better positioning accuracy
- Future plans: Expected growth in lifting capacity influences the choice
- Safety regulations: Certain industries require specific crane types
Budget considerations also play a role, where single girder systems require lower initial investments but may need to be replaced sooner with growing needs.
What are the cost and maintenance differences between both portal crane types?
Single girder portal cranes have 30-50% lower purchase costs than comparable double girder systems. Maintenance costs are also lower due to the simpler construction, but double girder cranes often have a longer lifespan of 25-30 years versus 15-20 years for single girder systems.
The total ownership costs differ significantly between both systems. Installation costs for single girder cranes are lower due to less complex foundations and shorter assembly time. Double girder systems require more robust foundations and more extensive electrical installations.
Maintenance frequency varies per crane type:
- Inspection costs: Double girder cranes require more extensive annual inspections
- Wear parts: Single girder systems have higher wear on the main beam
- Spare parts: Double girder components are often more expensive but readily available
- Downtime: Single girder maintenance can be performed faster
Energy consumption also differs, with double girder cranes being more efficient with heavy loads but consuming more energy during empty runs due to the higher dead weight of the system.
How does BKRS help in choosing the right portal crane for your business?
We analyze your specific lifting needs, operational conditions, and budget frameworks to determine the optimal portal crane configuration. Our advisory process combines more than 40 years of experience with advanced design capabilities for custom crane systems that perfectly align with your business processes.
Our expertise in portal cranes covers the complete spectrum from single girder to heavy double girder systems. We thoroughly assess your situation through site visits, capacity analyses, and evaluation of future plans. This results in a crane system that not only meets current requirements but also facilitates future growth.
Our complete service includes:
- Free consultation: Analysis of your lifting needs and location-specific requirements
- Technical design: 3D modeling and structural calculations for optimal performance
- Custom fabrication: Production in our workshop in Veghel with certified employees
- Complete assembly: Professional installation, testing, and delivery
- After-sales and maintenance: Annual inspections and preventive maintenance by certified specialists
As a certified inspection institute, we also provide mandatory annual inspections and certification. With one point of contact for the entire project, we eliminate coordination challenges and ensure timely delivery within budget.
Contact us for a non-binding consultation about your portal crane project. Our specialists are happy to visit your location to discuss possibilities and propose a suitable solution.
Frequently Asked Questions
How long does delivery and installation of a portal crane take?
Delivery time for standard portal cranes is 8-12 weeks, for custom systems 12-16 weeks. Installation takes on average 2-5 days depending on the complexity and size of the system.
What foundation requirements apply to portal cranes?
Single girder portal cranes require less heavy foundations than double girder systems. We calculate the exact foundation requirements based on soil investigation, crane capacity, and local conditions during the design process.
Can an existing portal crane be upgraded to higher capacity?
Upgrading is technically possible but often not cost-effective. The structure, foundation, and electrical installation must be fully evaluated. In many cases, replacement is more economical than extensive modifications.
What are the main safety certifications for portal cranes?
Portal cranes must comply with NEN-EN 15011 and have CE marking. Annual inspections by a certified inspection institute are mandatory, as well as operator training according to NEN 2767 for safe use.