Double Girder Underhung Bridge Crane | Underhung Overhead Crane

Short Video Description

This video shows a double girder underhung bridge crane designed for workshops, food processing plants, production facilities and other industrial buildings where available headroom and floor space are important. The underhung overhead crane travels below the runway structure and can be configured for efficient overhead material handling.

A double girder underhung bridge crane, also called a double girder suspension crane or under-running bridge crane, uses two main bridge girders with the end carriages running below the runway beam. The hoist trolley operates between or below the bridge girders according to the selected configuration.

Compared with a conventional top-running overhead crane, an underhung overhead crane can make better use of the upper area of a workshop. The runway can be suspended from the building structure or supported by a dedicated overhead structure, helping keep the floor area available for production equipment, storage and vehicle movement.

The double girder underhung crane is especially useful when the project requires greater bridge rigidity, higher lifting capacity, longer spans or a special hoist arrangement. The final design depends on the lifting capacity, span, lifting height, duty class, available headroom and building structure.

Yuantai engineers review the complete bridge girder, end carriage, hoist trolley, runway beam, wheel loads, building structure and working envelope before finalizing the underhung crane design.

Main Technical Specifications

What Is a Double Girder Underhung Bridge Crane?

A double girder underhung bridge crane is an overhead lifting crane with two main bridge girders that travels underneath an overhead runway system. The end carriages run on the lower flange or running surface of the runway beams.

The configuration is different from a conventional top-running double girder overhead crane. Instead of the bridge travelling on top of the runway rail, the under-running bridge crane travels below the runway structure.

This arrangement can be useful in buildings where the customer wants to maximize floor space, reduce floor-mounted runway columns or work within specific building geometry.

Why Choose a Double Girder Underhung Overhead Crane?

The main advantage of a double girder underhung overhead crane is the combination of overhead support and a rigid double-girder bridge structure. It can provide a practical solution when the crane must operate below the roof structure while maintaining good lifting coverage.

• Two bridge girders provide increased structural rigidity
• Suitable for higher-capacity underhung crane applications
• Can be designed for longer bridge spans
• Can reduce floor-level runway obstructions
• Suitable for workshops with limited floor space
• Can be configured for low headroom applications
• Suitable for production lines, warehouses and machinery plants

The actual benefits depend on the building structure, crane geometry, load requirements and runway arrangement. The underhung system should therefore be engineered according to the actual workshop conditions.

Double Girder Underhung vs Top Running Double Girder Crane

Double Girder Underhung Crane for Food Processing Workshops

A double girder underhung crane for food processing workshops can be used for equipment maintenance, machine component handling, production support and movement of auxiliary materials.

The crane does not normally handle food directly. Instead, it supports the material handling requirements around the production process, including processing equipment, motors, pumps, maintenance components, packaging machinery and production tools.

For food processing environments, the crane configuration should be selected according to the actual conditions, including humidity, temperature, cleaning procedures, washdown exposure, dust and required electrical protection.

Low Headroom Double Girder Underhung Bridge Crane

A low headroom underhung bridge crane is designed for workshops where the vertical distance between the roof structure, runway and required hook position is limited.

The under-running bridge arrangement allows the crane to travel below the runway beam. Depending on the building geometry and hoist design, this can provide an efficient solution for facilities where available headroom is a major design constraint.

Yuantai engineers check the runway beam depth, bridge girder height, hoist dimensions, hook height and required safety clearance together when developing a low headroom crane solution.

Main Design Factors for a Double Girder Underhung Overhead Crane

Typical Applications of Double Girder Underhung Bridge Cranes

A double girder underhung overhead crane can be used in:

• Food processing workshops
• Machinery manufacturing plants
• Industrial assembly workshops
• Equipment maintenance areas
• Production lines
• Warehouses
• Automotive component plants
• Packaging machinery facilities
• Industrial service workshops
• Buildings with limited floor space or special headroom requirements

How Yuantai Designs a Double Girder Underhung Bridge Crane

Yuantai Crane does not determine an underhung overhead crane from lifting capacity alone. The engineering team evaluates the complete crane and runway system according to the customer's actual building and operating conditions.

• Check the required lifting capacity
• Determine the required span and runway length
• Check the available headroom and hook height
• Select the appropriate double girder bridge structure
• Select the suitable electric hoist or crab trolley
• Calculate wheel loads and runway reactions
• Check the building structure
• Optimize the bridge end approach and hoist approach
• Select electrical and mechanical components according to the working environment

This engineering process allows Yuantai to develop a double girder underhung bridge crane that fits the actual building geometry rather than forcing the workshop to adapt to a standard crane design.

Need a Double Girder Underhung Bridge Crane?

Send us your lifting capacity, span, lifting height, runway length, available headroom, duty class, working frequency, power supply and workshop layout.

Yuantai Crane can engineer a double girder underhung bridge crane or underhung overhead crane according to your building structure, lifting requirements, production layout and operating environment.

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.

Follow: