Pivot / Spot Turning Mode in Rubber-Tyred Gantry Cranes

In modern container terminals, land is increasingly valuable, yard layouts are becoming denser, and operational flexibility has become a top priority for terminal operators. Rubber-tyred gantry (RTG) cranes continue to dominate yard operations due to their mobility and efficiency, but as container stacking grows more complex, traditional steering modes are no longer enough. This is where Pivot / Spot Turning Mode—one of the most advanced steering functionalities in RTG cranes—plays a crucial role. By allowing the crane to rotate around its own center point, this mode significantly improves maneuverability, reduces non-productive movement, and optimizes the overall flow of container handling operations.

This article explores what Pivot / Spot Turning Mode is, how it works, its advantages, common applications, and considerations for choosing an RTG crane with this advanced steering mode.

1. Understanding Pivot / Spot Turning Mode

Pivot or Spot Turning Mode is a specialized steering function designed to enable an RTG crane to rotate sharply—often almost within its own footprint—without requiring substantial forward or backward movement. Essentially, the crane acts as if it is “turning on the spot,” performing a tight-radius rotation that is impossible with conventional steering systems.

In this mode:

• One set of wheels turns forward,

• The opposite set turns backward,

• Allowing the crane to pivot around its geometric center.

This is particularly useful in areas where yard space is restricted or traffic flow is congested.

Key characteristics of Pivot / Spot Turning Mode include:

• Extremely small turning radius

• High steering angle coordination

• Real-time wheel alignment control through electronic or hydraulic steering systems

• Smooth rotational movement without causing excessive ground pressure

• Enhanced positioning accuracy

As container terminals adopt more automated processes and densify their layouts, the importance of such agile steering capabilities continues to grow.

2. How Pivot / Spot Turning Mode Works

RTG cranes are equipped with multiple wheel bogies, often with 8 or 16 wheels. In Pivot / Spot Turning Mode, the steering system—controlled through an advanced PLC and sensors—coordinates the wheels in opposing directions to create a rotational force.

Operational Steps

1. Mode SelectionThe operator (or automated system) selects Pivot / Spot Turning Mode via the control interface.

2. Wheel Alignment SynchronizationEach wheel bogie aligns to predetermined steering angles. Some systems allow up to ±110° steering.

3. Opposing Drive MechanismMotors on one side drive forward while motors on the opposite side reverse.

4. Center-Point RotationThe crane begins rotating around a fixed pivot point, usually at the geometric center of the crane frame.

5. Real-Time CorrectionSensors continuously adjust motor speeds and wheel angles to maintain a stable rotation.

This precise coordination is made possible through advanced steering control systems used in modern RTG cranes, such as electronic differential controls, intelligent anti-skid systems, and steering angle feedback loops.

3. Key Advantages of Pivot / Spot Turning Mode

3.1 Maximum Maneuverability in Tight Spaces

Container terminals are often congested, especially during peak operations. Pivot turning allows RTGs to navigate:

• Narrow aisles

• Intersections

• Stacking row ends

• Maintenance areas

• Corners of the yard

This level of agility helps minimize traffic delays and avoid unnecessary crane repositioning.

3.2 Reduced Non-Productive Travel

Non-productive movement—travel that does not involve container handling—directly increases operational cost. With Pivot or Spot Turning Mode, the crane reaches its next working position faster by:

• Minimizing travel distance

• Reducing back-and-forth adjustments

• Allowing direct rotational repositioning

This improves cycle time, leading to higher crane productivity.

3.3 Better Utilization of Yard Space

Terminals that operate in limited land areas can redesign stacking blocks to maximize container density. Pivot turning allows cranes to operate efficiently in tighter configurations, enabling:

• More rows per block

• Smaller turning pockets

• Reduced aisle width requirements

Ultimately, operators gain more storage capacity without physical expansion.

3.4 Enhanced Safety and Collision Avoidance

Tight locations increase the risk of collisions. Pivot turning reduces this by:

• Eliminating unnecessary side movements

• Offering precise directional control

• Improving visibility and predictability of crane motion

When integrated with anti-collision sensors, the crane can safely rotate even in high-traffic zones.

3.5 Lower Tire and Ground Wear

Compared with traditional braking and turning movements that create lateral friction, Pivot Turning Mode:

• Reduces tire scrubbing

• Minimizes surface abrasion

• Extends tire service life

• Lowers pavement maintenance costs

This is especially important in terminals using heavy duty gantry cranes with multiple wheel sets.

4. Practical Applications in Terminal Operations

4.1 Repositioning at Block Ends

When working along container aisles, cranes often need to turn around at block ends. Pivot turning significantly speeds up this process.

4.2 Navigating Around Obstacles

Yards commonly have fixed obstacles like power stations, lighting structures, and reefer racks. Spot turning helps cranes avoid these efficiently.

4.3 Maintenance Yard Maneuvering

Workshop and maintenance areas often have narrow lanes—pivot turning makes movement safer and smoother.

4.4 Hybrid and Electric RTG Operations

With the growing adoption of hybrid and electric RTGs, efficient movement modes like pivot turning reduce energy consumption and extend battery runtime.

5. Choosing an RTG Crane with Pivot / Spot Turning Mode

When evaluating RTG cranes with pivot turning capability, terminal operators should consider several technical and operational factors.

5.1 Steering System Type

Modern RTG cranes typically use:

• Electronic-hydraulic steering systems

• Fully electric steering systems (common in e-RTGs)

The system must support synchronized wheel control with high steering angles.

5.2 Wheel Bogie Configuration

More bogies mean increased stability but require more complex control. Verify:

• Number of wheels

• Steering capability per wheel

• Load distribution

5.3 Energy Consumption and Power Demand

Pivot turning typically requires higher momentary power. Hybrid and battery RTGs must be sized adequately to handle these loads.

5.4 Automation Compatibility

For semi-automated or fully automated terminals, pivot turning should integrate seamlessly with:

• Auto-steering

• Auto-positioning

• Path planning systems

5.5 Safety and Redundancy Systems

Look for features like:

• Wheel angle sensors

• Real-time position monitoring

• Automatic emergency stops

• Anti-skid control

• Collision avoidance barriers

These ensure safe pivot operation even in crowded yards.

6. Conclusion

Pivot / Spot Turning Mode is one of the most valuable steering functionalities in modern rubber-tyred gantry cranes. As terminals expand their operations and container volumes increase, the need for cranes that can maneuver precisely and operate efficiently within limited yard space has never been more critical. This powerful steering mode helps reduce non-productive travel, increase yard density, enhance safety, minimize wear, and support the operational flexibility required in today’s competitive port environments.

For terminals seeking to modernize their yard equipment or improve existing RTG operations, selecting a crane with advanced steering capabilities—especially pivot turning—offers long-term benefits that directly contribute to operational efficiency, cost reduction, and better yard throughput.