Rubber Tyre Travelling System Features of RTG Cranes

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The Rubber Tyred Gantry (RTG) crane is a cornerstone of modern container terminals and industrial yards. Its most distinctive advantage over rail-mounted alternatives lies in the rubber tyre travelling system, which enables flexible, rail-free movement while carrying heavy loads.

To clearly understand its value, this article presents the rubber tyre travelling system features of rubber tire cranes in a well-defined hierarchical structure, moving from core concepts to detailed technical characteristics and operational benefits.

rubber tire crane

1. Overview of the Rubber Tyre Travelling System

1.1 Definition and Role

The rubber tyre travelling system is the mechanism that allows an RTG crane to move across the yard using heavy-duty rubber tyres instead of steel wheels on rails. It includes tyres, wheel assemblies, drive units, steering mechanisms, braking systems, and control logic.

1.2 Why It Is a Core RTG Feature

This system directly determines:

  • Yard layout flexibility

  • Crane mobility and positioning accuracy

  • Pavement requirements

  • Operating efficiency and lifecycle cost

Without the rubber tyre travelling system, the RTG would lose its defining advantage of free movement.

2. Rail-Free Mobility Features

2.1 Operation Without Fixed Infrastructure

A fundamental feature of RTG travelling systems is rail-free operation. The mobile gantry cranes move directly on concrete or asphalt pavement, eliminating the need for rails, sleepers, and alignment work.

2.2 Benefits for Yard Planning

This feature enables:

  • Flexible container block arrangement

  • Easy yard expansion or reconfiguration

  • Lower initial civil construction investment

Terminals can adapt quickly to changes in cargo volume or operational strategy.

3. Heavy-Duty Rubber Tyre Design Features

3.1 High Load-Bearing Capacity

RTG tyres are specially designed industrial tyres capable of supporting:

  • Crane self-weight

  • Rated lifting loads

  • Dynamic forces during acceleration and braking

Each tyre is engineered with high ply ratings and reinforced internal structures.

3.2 Optimized Ground Contact

Rubber tyres provide a larger contact area than steel wheels, which:

  • Reduces ground pressure

  • Protects yard pavement

  • Improves overall travelling stability

This makes RTGs suitable for long-term operation on reinforced surfaces.

rubber tire gantry crane

4. Multi-Wheel Configuration Features

4.1 Typical Wheel Arrangements

RTG cranes commonly use:

  • 8-wheel configurations for smaller RTGs

  • 12-wheel or 16-wheel configurations for higher capacities

4.2 Load Distribution Advantages

Multiple wheels evenly distribute loads across the ground, which:

  • Minimizes local pavement stress

  • Enhances gantry crane stability

  • Reduces structural fatigue

This feature is critical for heavy-duty container handling.

5. Steering System Features

5.1 Multi-Mode Steering Capability

The rubber tyre travelling system supports multiple steering modes, including:

  • Straight-line steering for long-distance travel

  • Ackermann steering for smooth turning

  • Crab steering for lateral movement

  • Pivot or zero-radius steering for tight spaces

5.2 Precision Positioning

These steering features allow RTG cranes to:

  • Accurately align with container rows

  • Reposition efficiently between blocks

  • Operate in confined yard layouts

High steering precision directly improves yard productivity.

6. Drive and Speed Control Features

6.1 Independent Wheel or Axle Drives

Most RTG travelling systems use electric motor drives, often with one motor per wheel or axle. This allows:

  • Balanced torque distribution

  • Improved traction control

  • Redundancy in case of component failure

6.2 Variable Speed Control

With variable frequency drives (VFDs), the system provides:

  • Smooth acceleration

  • Controlled deceleration

  • Stable low-speed movement

These features are essential when travelling with suspended loads.

7. Anti-Skid and Traction Control Features

7.1 Adaptation to Outdoor Conditions

RTG cranes operate in open environments where surfaces may be wet, dusty, or uneven. Rubber tyre travelling systems include anti-skid features such as:

  • Wheel speed monitoring

  • Torque limitation control

  • Automatic traction adjustment

7.2 Safety and Tyre Protection

These features:

  • Prevent wheel slip during braking or turning

  • Improve crane controllability

  • Reduce abnormal tyre wear

This results in safer and more reliable operation.

8. Stability Features During Travel

8.1 Stability With and Without Load

The travelling system is designed to maintain stability:

  • During unloaded repositioning

  • While travelling with containers lifted

Wide wheel spacing and optimized tyre characteristics minimize the risk of tipping or excessive sway.

8.2 Controlled Braking Performance

Advanced braking systems ensure:

  • Short stopping distances

  • Even braking forces across wheels

  • Stable crane behavior under emergency stops

Stability during braking is a key safety requirement.

9. Shock Absorption and Vibration Reduction Features

9.1 Natural Elasticity of Rubber Tyres

Rubber tyres inherently absorb shocks caused by:

  • Pavement joints

  • Minor surface irregularities

This reduces vibration transmission to the crane structure.

9.2 Structural Protection Benefits

Shock absorption helps:

  • Extend steel structure fatigue life

  • Protect mechanical components

  • Improve reliability of electrical systems

It contributes to long-term durability of the RTG wheeled gantry crane.

10. Noise Reduction Features

10.1 Comparison With Rail-Based Systems

Rubber tyre travelling systems generate significantly less noise than steel wheel rail systems.

10.2 Environmental and Operational Benefits

Lower noise levels:

  • Improve operator comfort

  • Reduce environmental impact

  • Support compliance with port noise regulations

This feature is increasingly important for terminals near urban areas.

11. Maintenance and Serviceability Features

11.1 Easy Inspection and Replacement

Tyres can be:

  • Inspected visually

  • Replaced individually

  • Maintained without dismantling major structures

This minimizes crane downtime.

11.2 Predictable Maintenance Cycles

Tyre wear is gradual and predictable, allowing:

  • Planned maintenance

  • Lower unplanned shutdown risk

  • Better spare parts management

12. Adaptability to Different Yard Conditions

12.1 Pavement and Site Adaptation

By selecting suitable tyre specifications and wheel layouts, RTG travelling systems can adapt to:

  • Different pavement strengths

  • Slight slopes or gradients

  • Mixed operational surfaces

12.2 Application Flexibility

This adaptability makes RTGs suitable for:

  • Container terminals

  • Steel yards

  • Logistics and intermodal facilities

13. Contribution to Overall RTG Performance

The rubber tyre travelling system directly influences:

  • Crane mobility

  • Yard utilization efficiency

  • Operating safety

  • Total cost of ownership

When combined with modern control and automation technologies, it supports high-throughput, flexible, and future-ready RTG operations.

Conclusion

The rubber tyre travelling system is a defining feature of RTG cranes and a major reason for their widespread adoption. Through rail-free mobility, advanced steering, stable load handling, shock absorption, and low maintenance requirements, this system delivers unmatched flexibility and efficiency.

A well-designed rubber tyre travelling system not only enhances day-to-day operations but also ensures long-term reliability, safety, and cost-effectiveness. For ports and industrial yards seeking adaptable and high-performance lifting solutions, understanding these travelling system features is essential for selecting the right RTG crane configuration.