U-Type Double Girder Gantry Crane

When your projects require large lifting capabilities combined with maximum ground-level workspace, the U-Type Double Girder Gantry Crane is an excellent choice. This specialized gantry crane is commonly known as an MG U-type gantry crane or a U-shaped twin beam gantry crane. It can deliver reliable performance, especially in outside yards, storage areas, and workshops where access between crane legs is required. Unlike standard A-frame gantry cranes, the U-shaped leg design greatly increases the gap between the support legs. This characteristic makes it easier to handle heavy, bulky goods and pass trucks and other equipment through the crane's structure.

What Is A U-Type Double Girder Gantry Crane?

A U-Type Double Girder Gantry Crane is a variation of the standard double girder gantry crane characterized by its distinctive U-shaped support legs. It operates on ground-level rails (runway rails) and consists of two main girders spanning the workspace, supported by these U-shaped legs at each end.

Key elements include:

• Double Girders: The bridge of the gantry crane is formed by two parallel main beams, known as double girders. This configuration enhances the structural integrity of the crane, offering superior strength and stability. It is particularly well-suited for handling heavy loads and spanning long distances, ensuring reliable performance in demanding industrial environments.

• U-Shaped Legs: Unlike traditional A-frame legs that angle inward, this design features vertical, U-shaped legs that extend straight from the ground to the top of the crane. These legs connect directly to the end carriages (or saddles) at the bottom and provide robust support to the main girders at the top. The U-shape creates a wide, unobstructed space between the legs, allowing for easier movement of large or awkwardly shaped loads and equipment.

• End Carriages / Saddles: Positioned at both ends of the crane, the end carriages—or saddles—serve as the structural base for the U-shaped legs and house the critical drive components. These include the wheels and drive mechanisms that enable the entire crane to move smoothly along floor-mounted rails.

• Trolley Hoist (Crab Unit): This is the primary lifting assembly of the crane. It includes the hoist, motor, gearbox, brake system, and supporting frame, all mounted on a compact trolley. This unit travels laterally along the rails affixed to the top of the double girders, enabling controlled horizontal movement of loads across the crane span.

• Crane Travel Mechanism: The longitudinal movement of the gantry crane is powered by motors and gearboxes installed on the end carriages. These components drive the wheels that run along the ground-level rails, allowing the entire structure to traverse back and forth as needed within the designated work area.

The defining characteristic – the U-shape – is specifically engineered to provide greater clearance than A-frame designs, making it suitable for applications where space between the legs is a functional requirement.

Key Features Of U-Type Double Girder Gantry Cranes From Yuantaicrane

Our U-shaped double beam gantry cranes are designed with performance, durability, and operational efficiency in mind:

• Optimized Workspace: The primary feature is the increased legroom provided by the U-shaped leg structure, facilitating easier handling of oversized loads and allowing passage for vehicles or forklifts.

• Heavy Lifting Capacity: The double girder design provides excellent load-bearing capability, suitable for lifting capacities typically ranging from 5 tons up to several hundred tons (though this page focuses on general features applicable across capacities).

• Robust Construction: Built using high-quality steel (e.g., Q235B, Q345B) and advanced welding techniques, ensuring structural integrity and longevity under demanding industrial conditions. Box-girder designs are commonly used for the main beams for high torsional stiffness.

• Smooth and Precise Operation: Equipped with reliable hoisting and travel mechanisms. Options for Variable Frequency Drives (VFDs) on hoist, trolley, and crane travel motors allow for smooth acceleration/deceleration, reduced load sway, and precise positioning.

• Multiple Control Options: Choose from pendant control (push-button box), wireless radio remote control for enhanced operator mobility and visibility, or cabin control for high-frequency use or complex operations.

• Safety Mechanisms: Incorporates standard safety features like overload limit switches, hoist upper/lower limit switches, travel limit switches, emergency stop buttons, and robust braking systems on all motions.

• Durability for Outdoor Use: Designed to withstand outdoor environmental conditions with appropriate surface treatments (sandblasting, primer, finishing paint) and optional features like rain covers for motors and electrical components.

• Rail-Mounted Operation: Designed for stable and predictable movement along fixed ground rails, suitable for defined operational areas.

Advantages Of The U-Shape Design

The specific geometry of the U-type gantry crane legs offers distinct operational benefits compared to A-frame gantry cranes:

• Increased Transverse Space: The most notable advantage is the significantly larger clear space between the crane legs. This allows for:

  • Handling of very long or wide loads (like pipes, beams, prefabricated sections, containers) that might not easily fit through the narrower base of an A-frame.

  • Passage of trucks, trailers, forklifts, or other mobile equipment directly beneath the crane span, improving logistical flow within the work area.

  • Easier positioning of loads onto transport vehicles parked between the rails.

• Improved Loading/Unloading Efficiency: The open design can simplify the process of loading and unloading materials from trucks or rail cars positioned within the crane's operating path.

• Enhanced Workflow in Storage Yards: In stockyards or storage areas, the ability for vehicles to move freely between the legs can optimize space utilization and material handling processes.

While offering these spatial advantages, the design requires careful engineering to ensure stability, particularly under load and during travel. Yuantaicrane's engineering practices address these structural demands.

Main Components (Parts) Of A U-Type Double Girder Gantry Crane

Understanding the components helps appreciate the crane's functionality:

1. Main Girders: Typically two box-type girders forming the crane bridge. They bear the load and support the trolley rails. Walkways with handrails can often be included along the girders for maintenance access.

2. U-Shaped Support Legs: The vertical steel structures connecting the main girders to the end carriages. Their shape defines the crane type and provides the large inter-leg clearance.

3. End Carriages (Saddles / End Trucks): Fabricated steel structures at the base of the legs containing the crane travel wheels, bearings, buffers, and drive units (motors, gearboxes, brakes) for longitudinal movement along the ground rails.

4. Trolley Hoist (Crab Unit): The unit that travels across the main girders. It includes:

   • Hoist Mechanism: Houses the motor, gearbox, drum, wire rope, and hook block for lifting and lowering the load.

   • Trolley Frame: The structural base of the unit.

   • Trolley Travel Mechanism: Motors, gearboxes, and wheels enabling cross-travel movement.

5. Crane Travel Mechanism: Located on the end carriages, this system propels the entire gantry structure along the runway rails. It usually involves electric motors driving the wheels through gear reducers.

6. Electrical System: Includes the main power supply system (often a cable reel or festoon system), control panels, motors, limit switches, wiring, and safety devices.

7. Control System: Pendant control, wireless radio remote, or operator cabin, providing the interface for operating the crane's motions.

8. Runway Rails: Steel rails installed at ground level on a suitable foundation, providing the path for the gantry crane to travel along.

Common Applications

The U-type double girder gantry crane is designed for versatility and efficiency in environments that demand both heavy lifting and open space beneath the crane structure. Its unique U-shaped leg configuration allows for easier access and movement of materials, making it a practical solution across several industries.

• Outdoor Storage Yards: Ideal for steel yards, precast concrete facilities, lumber yards, and general material storage areas where large items are handled and vehicle access between the legs is beneficial.

• Container Handling: U-type gantry cranes are also well-suited for small to mid-sized container terminals and logistics depots. The wide spacing between the legs accommodates the dimensions of standard ISO containers, allowing operators to lift, stack, and move containers with greater ease.

• Shipbuilding Yards: The crane is especially valuable in shipyards where large structural components such as hull sections, blocks, and machinery need to be moved with precision. The generous clearance between the legs ensures smooth handling of oversized parts without obstruction.

• Bridge Construction Projects: During bridge construction, these cranes are used on-site to lift and position massive precast segments. Their ability to handle long spans and high loads makes them a reliable tool for aligning components accurately during assembly.

• Railway Freight Yards: In rail freight operations, the U-type gantry crane helps with loading and unloading goods from railcars. Its ability to span tracks and move freely along the yard increases operational efficiency and reduces turnaround time.

Choosing The Right U-Type Gantry Crane

Selecting the appropriate U-shaped double beam gantry crane requires careful consideration of your operational needs. Key factors include:

1. Required Lifting Capacity (SWL - Safe Working Load): Determine the maximum weight you need to lift, ensuring a suitable safety margin. Capacities for this type range widely.

2. Span (S): The horizontal distance between the centerlines of the runway rails. This must match your site dimensions and required coverage area. The U-type design often allows for substantial spans.

3. Lifting Height (H): The vertical distance from the ground level to the highest hook position. This must be sufficient for lifting loads over obstacles or onto transport.

4. Cantilever Length (Optional): Decide if you need one or two cantilevers extending beyond the runway rails to increase the working area. Specify the required length and capacity on the cantilever(s).

5. Crane Travel Length (L): The total length of the runway rails, defining the crane's longitudinal working range.

6. Work Duty / Service Classification (FEM/ISO/CMAA): Determine how intensively the crane will be used (number of lifts per hour, percentage of lifts near maximum capacity). This dictates the required classification (e.g., A3, A4, A5, A6 or FEM 1Am, 2m, 3m) ensuring components are designed for the expected workload.

7. Operating Speeds: Specify the desired speeds for hoisting, trolley travel, and crane travel. Consider if variable speed control (VFD) is needed for precision.

8. Operating Environment: Indoor or outdoor use? Are there extreme temperatures, dusty conditions, corrosive atmospheres, or specific wind load requirements? This impacts material selection, paint systems, and component protection.

9. Control Method: Choose between pendant, radio remote, or cabin control based on operational flow, safety, and operator comfort.

10. Power Supply: Specify the site's available voltage, frequency, and phases (e.g., 380V/50Hz/3Ph, 480V/60Hz/3Ph). Determine the preferred power feeding method (cable reel, festoon system).

Consulting with Yuantaicrane engineers can help ensure all factors are considered for an optimal U-type gantry crane specification.

Customization Options For Your U-Type Gantry Crane

At Yuantaicrane, we recognize that every operation has its own unique challenges. That’s why our MG U-type double girder gantry cranes can be fully customized to meet specific operational, environmental, and safety requirements. Below are the key customization options available:

• Specific Capacities, Spans, and Heights:Every crane can be engineered to fit your exact specifications. Whether you need greater lifting capacity, a longer span, or a taller clearance height, we will tailor the design to match your operational needs and site constraints.

• Cantilever Design: Addition of single or double cantilevers with specified lengths and capacities.

• Auxiliary Hoist: An additional hoist—typically of lower capacity—can be installed alongside the main hoist. This is useful for handling smaller loads independently, speeding up workflows, or performing delicate tasks such as load rotation or fine positioning.

• Variable Speed Control (VFD): For smoother and more precise crane movements, VFDs can be integrated into any or all motion systems. This allows for gradual acceleration and deceleration, minimizing load swing and improving overall control and safety.

• Specialized Lifting Attachments: We can equip the crane with custom below-the-hook devices suited to your materials. These include magnetic lifters, spreader beams, C-hooks, grabs, and more—designed to handle everything from steel coils to containers to bulk materials.

• Enhanced Environmental Protection: For cranes operating in harsh environments, we offer protective features such as anti-corrosion paint systems, rain shields for outdoor components, and space heaters in control panels to prevent moisture-related failures.

• Cabin Features: Operator comfort and efficiency are critical. Our cabins can be outfitted with air conditioning, heating, ergonomic seating, and customized control layouts tailored to user preference and site-specific functions.

• Automation Features: For repetitive or precision-based tasks, we offer semi-automated and fully automated systems. These can include programmable load positioning, path tracking, hook tracking dystemand motion synchronization for improved workflow consistency.

• Walkways and Maintenance Platforms: We can design and install safe walkways and service platforms along the girders or legs. These provide convenient access for routine maintenance and inspections, improving safety and reducing downtime.

• Anti-Collision Systems: To prevent accidents and protect your equipment, we offer advanced sensor-based anti-collision systems. These can detect nearby obstacles or other cranes and initiate alerts or automatic stops as needed.

• Load Display Systems: Digital load indicators can be added to show real-time weight data to the operator. This feature helps prevent overloading and enhances safety during lifting operations.

Precautions For Safe Use

Operating a heavy-duty U-type gantry crane requires strict adherence to safety protocols:

• Operator Qualification: Ensure only trained, certified, and authorized personnel operate the crane.

• Pre-Operation Inspection: Conduct daily checks before starting operations. Verify hoist limits, travel limits, brakes, wire rope condition, hook safety latch, warning devices, and control functions.

• Know Your Load: Never exceed the crane's rated load capacity (SWL). Ensure the load is properly rigged and balanced before lifting.

• Clear Path: Confirm the travel path for the crane and the load is clear of personnel and obstructions. Use warning signals (horn/beacon) when moving the crane or load.

• Smooth Operation: Avoid abrupt starts and stops. Use VFD controls (if equipped) for smooth acceleration and deceleration to minimize load swing.

• No Side Pulling: Do not use the crane to pull loads sideways; lift vertically.

• Environmental Limits: Do not operate the crane in high winds or weather conditions exceeding its design limits.

• Secure During Idle Periods: When not in use, raise the hook, move the crane to its designated parking area, and engage storm brakes or rail clamps if outdoors.

• Emergency Procedures: Ensure operators know the location and function of the emergency stop button and understand emergency shutdown procedures.

• Maintenance Lockout/Tagout: Follow proper lockout/tagout procedures before performing any maintenance or repairs.

Maintenance Guidelines For Longevity

Regular maintenance is essential for the safe and reliable operation of your U-type double girder gantry crane:

• Regular Inspections: Implement a schedule for frequent (daily/weekly) and periodic (monthly/annual) inspections as per manufacturer recommendations and applicable regulations. Check structural components, wire rope, hooks, sheaves, brakes, limit switches, wheels, rails, and electrical systems.

• Lubrication: Follow the lubrication schedule specified by Yuantaicrane for gearboxes, bearings, wire rope, and other moving parts using the recommended lubricants.

• Component Checks: Regularly inspect brakes for proper function and wear. Check wire rope for signs of damage (broken wires, kinking, corrosion). Inspect hook and safety latch. Monitor wheel wear and alignment.

• Structural Integrity: Periodically inspect girders, legs, and connections for any signs of deformation, cracking, or corrosion. Check bolt tightness.

• Electrical System Maintenance: Inspect control panels, wiring, festoon cables or cable reel, motors, and limit switches for wear, damage, or loose connections. Keep electrical enclosures clean and dry.

• Cleaning: Keep the crane structure, trolley, and mechanisms reasonably clean to allow for easier inspection and prevent buildup that could interfere with operation.

• Record Keeping: Maintain detailed records of all inspections, maintenance activities, and repairs performed.

Adhering to a preventive maintenance program helps maximize uptime, extend the crane's service life, and maintain safe operating conditions.

Why Choose Yuantaicrane For Your U-Type Gantry Crane?

Partnering with Yuantaicrane for your U-shaped double girder gantry crane provides several advantages:

• Specialized Experience: We possess considerable experience in designing and manufacturing various types of gantry cranes, including the specialized U-type configuration.

• Engineering Strength: Our qualified engineers use current design software and adhere to international standards (FEM, ISO, CMAA) to create robust and reliable crane solutions.

• Quality Manufacturing: Our production facilities employ modern fabrication techniques and rigorous quality control procedures from raw material inspection to final testing.

• Customization Capability: We work closely with clients to understand their unique needs and provide tailored U-type gantry crane solutions.

• Safety Commitment: Safety is embedded in our design philosophy. We incorporate required safety features and ensure compliance with relevant safety standards.

• Full Project Support: Yuantaicrane offers comprehensive support, including consultation, design, manufacturing, delivery, installation supervision, commissioning, training, and after-sales service.

Get Your Customized U-Type Gantry Crane Solution

If the unique workspace advantages and heavy lifting power of a U-Type Double Girder Gantry Crane align with your operational requirements, Yuantaicrane is here to help. We can provide a durable, efficient, and safe lifting solution tailored precisely to your application, whether for an outdoor yard, fabrication shop, or specialized industrial site.

Contact our expert team today to discuss your lifting challenges. We will provide technical consultation, assist with specifications, and offer a detailed quote for the U-type gantry crane that best fits your needs.

How to get quotation?

Send us your RFQ including the parameters above, we will reply our quotation accordingly.