• Jan 09, 2025
• News

What Are the Parts of the RTG?

The parts of a Rubber Tired Gantry Crane (RTG) include the steel frame, main girder, operator cabin, hoist drums, trolley, and both horizontal and diagonal beams.

A tire gantry crane is usually a lifting device used in terminals or ports, and is often used to move containers. This article focuses on the components, operation and specifications of these cranes.

Introduction to RTG Cranes

RTG container cranes, widely used in ports and industrial facilities, are mobile gantry cranes designed for stacking and transporting containers. Unlike rail-mounted gantry cranes, RTGs are equipped with rubber tires, allowing them to maneuver across container yards without the need for fixed tracks. Therefore, RTG cranes are often flexible enough to handle containers flexibly in ports.

Essential Parts of an RTG Crane

1. Gantry Frame

The gantry frame provides the rigid support structure for both the trolley and hoist. It must carry the full span loads and resist bending under dynamic conditions. Ensure the frame uses high-strength steel—such as S355 or Q345B—and that all welds pass non-destructive testing. Check that corrosion protection, like hot-dip galvanizing or industrial paint, covers every surface. Finally, confirm the frame's rated capacity meets or exceeds the maximum container weight you intend to lift.

2. Trolley and Hoist

The trolley runs smoothly along the girder, carrying the hoist motor and drum assembly. Reliable drive motors and well-lubricated wheels ensure precise travel under load. The hoist lifts and lowers the spreader via wire rope or chain. Examine the brake design—spring-applied, electrically released brakes give positive load holding. Verify lifting speeds match your cycle requirements and that overload sensors interrupt operations when limits are exceeded.

3. Spreader

The spreader connects directly to a container's corner castings, enabling secure engagement and release. Semi-automatic models require manual twistlock operation, while fully automatic versions lock and unlock via hydraulic or electric actuation. Automatic spreaders cut cycle times by removing manual steps. Make sure the twistlock mechanism adheres to ISO 1161 standards and that the spreader's lateral and longitudinal slide adjustments cover your container types.

4. Lifting Beams and Cables

Lifting beams distribute the load from the spreader to the hoist hook, keeping forces balanced. They must stay within deflection limits—typically L/500 under full load—to avoid undue stress on the hoist. Wire ropes or load chains then carry the weight upward. Choose materials with a safety factor of at least 5:1 and confirm that rope or chain grade matches your hoist's capacity. Inspect for kinks, corrosion, or wear that can compromise strength.

5. Undercarriage and Tires

Rubber-tyred undercarriages let the crane roll across yard surfaces without fixed rails. Select tire compounds engineered for your conditions—softer compounds for abrasive surfaces, harder for oily or wet zones. The steering system—whether two-wheel or four-wheel—must provide tight turning control to minimize tire scrub and wear. Test steering precision under load to ensure the crane can navigate congested areas safely.

6. Power and Drive System

You can power the crane with a diesel-electric generator or tap into facility power for fully electric operation. Compare diesel models on fuel consumption and emissions, and electric versions on voltage compatibility and grid load. Drive motors equipped with variable-frequency drives (VFDs) deliver smooth acceleration and deceleration. VFDs also reduce peak current draw and lower energy costs over continuous operation.

7. Control Cabin and Electronics

The operator cabin should offer an ergonomic console layout, heated or air-conditioned environment, and vibration damping. Unobstructed sightlines through tempered safety glass improve load placement accuracy. Behind the scenes, a PLC or microcontroller handles motion sequencing and safety interlocks. Look for user-friendly diagnostic interfaces that let technicians read fault codes and adjust parameters without complex programming.

8. Safety and Monitoring Systems

Limit switches at each axis—bridge travel, trolley travel, and hoist lift—prevent over-travel and mechanical overrun. Load-monitoring systems display real-time lift weights and trigger alarms or lockouts when thresholds are approached. Anti-collision modules use radar or laser sensors to detect nearby cranes or obstacles and automatically slow or stop motions. Together, these systems protect both equipment and personnel in busy yard environments.

9. Cabling and Power Collection

Festoon cable systems supply power to moving parts via trolleys that ride along overhead supports. Inspect festoon trolleys and carriers for smooth operation and easy cable replacement. Alternatively, busbar conductors or spring-reel cable reels offer a low-maintenance power feed. Choose the method that balances your maintenance capacity against initial installation complexity.

10. Lighting and Accessories

LED work lights mounted beneath the spreader illuminate the container's corner castings for accurate engagement. Their low power draw and long life fit heavy-use cycles. Integrated cameras or 3D sensors can further aid in spreader positioning and monitoring. Ensure any accessory interfaces seamlessly with the crane's control system to avoid signal conflicts or delay.

Application of RTG Cranes

RTG cranes are widely used in container terminals and intermodal yards. Their primary role is stacking and moving shipping containers in the yard after they are unloaded from vessels or trains. These cranes help manage container storage efficiently and support quick container retrieval for outbound transport.

1. 1. Container Terminals

RTG cranes are commonly deployed in port container yards. They move along rubber tyres, which means they do not require rails. This mobility allows flexible operations across different yard blocks. They are suitable for stacking containers up to 5–8 tiers high and 6–8 rows wide. This improves space usage without the need for permanent track installation.

2. Intermodal and Rail Yards

In rail freight yards, RTG cranes transfer containers between rail cars and trucks. They are used where rail and road transport are integrated. Their ability to move between tracks and yard lanes makes them suitable for cross-docking operations and high container turnover.

3. Inland Container Depots (ICDs)

Inland depots and dry ports use RTG cranes to handle container stacking, loading, and unloading. These facilities are usually located away from seaports and need efficient handling equipment to support local and regional distribution. RTG cranes offer a solution where space is limited and the container handling demand is high.

4. Container Storage and Logistics Centers

Private logistics companies and warehouse operators use RTG cranes to manage container yards that support distribution hubs. RTGs help streamline operations and reduce truck waiting time. Their ability to work on uneven or non-reinforced ground can lower infrastructure development costs.

RTG Crane Specification and Dimensions

RTG crane specifications and dimensions vary depending on their application. Typical specifications include:

• Lifting Capacity: Ranges from 30 to 60 tons, depending on the model.
• Span: Generally between 20 to 30 meters, accommodating six to eight containers across.
• Height: Designed to stack containers up to five or six levels high.
• Travel Speed: Can reach up to 120 meters per minute, ensuring efficient container handling.

These dimensions and specifications allow RTG cranes to excel in container stacking and logistics, making them a preferred choice for port terminals and industrial warehouses.

Why Choose RTG Cranes?

Rubber-tyred gantry (RTG) cranes offer a mobile, versatile solution for material handling in outdoor yards. They combine heavy-lift capacity with off-road mobility. You won’t need fixed rails or extensive foundation work. Their adaptable design serves varied stacking, loading, and maintenance tasks. Below are the key reasons to consider RTGs for your facility.

1. Operational Flexibility

RTG cranes roll on large, industrial-grade rubber tires instead of fixed rails. You can reposition them anywhere within a yard without new civil works. This flexibility lets you adapt layouts as needs change—whether shifting container stacks, moving precast elements, or rearranging raw material piles. You avoid the downtime and cost of laying or modifying rails.

2. High Stacking Capacity

Designed to lift loads up to 30 t or more, RTGs stack containers, steel bundles, or precast panels as high as site clearances allow. Their precise spreader and dual-hoist designs keep loads level during lifts and moves. By increasing vertical stacking, you free up valuable ground space. This efficient footprint maximizes storage in confined yards.

3. Fuel or Electric Options

You can choose diesel-electric, hybrid, or fully electric powerplants for your RTG. Diesel-electric models deliver high torque and widespread service support. Hybrid units cut fuel use by regenerating energy during braking. All-electric versions draw from the grid or on-site renewables, eliminating local emissions. This range lets you meet evolving environmental and operational targets.

4. Lower Infrastructure Costs

Without the need for embedded rails, RTGs save on groundwork and reinforcement. Their tires distribute heavy loads across a broader surface, reducing pavement stress. You avoid deep concrete foundations and rail-bed construction. The result is lower upfront investment and faster deployment. Your yard stays adaptable for future changes.

RTG Cranes for Sale

Ask for Price

When considering an RTG crane purchase, factors like rtg crane dimensions, lifting capacity, and energy efficiency should be prioritized. Reliable manufacturers offer a wide range of RTG cranes tailored to meet specific operational requirements. Yuantai offers RTG cranes and a wide range of gantry cranes, overhead cranes, and jib cranes, with customized products to meet your needs, whatever they may be.

Conclusion

When considering an RTG crane purchase, factors like rtg crane dimensions, lifting capacity, and energy efficiency should be prioritized. Yuantai is a reliable manufacturers that offer a wide range of RTG cranes tailored to meet specific operational requirements. RTG cranes are flexible, efficient and maneuverable cranes that operate without laying tracks, saving track costs.