Following our previous article, "STS Cranes Use Ultra-Large Outreach and Ultra-High Efficiency to Become the 'Quayside Backbone' for Ship-to-Shore Container Handling at Terminals," we have already seen how STS cranes, with their front booms reaching over the ship's rail and their ability to complete dozens of cycles per minute, transfer containers from vessels to the dock or from the dock onto vessels. However, once the cargo is exchanged between ship and shore, the next question follows immediately: How are containers unloaded from the quayside quickly and orderly transferred to the rear yard? How can more containers be stacked within a limited yard area? How can a specific container be retrieved efficiently and accurately when needed?
The RTG crane is precisely the core answer to this "yard operation" challenge. With its rubber tyres enabling rail-free travel and its multi-mode steering allowing flexible movement through container yards, it dramatically improves yard utilization with high-density stacking capabilities, becoming the mainstream workhorse for container terminal yard operations worldwide. However, many RTGs on the market suffer from chronic issues such as "travel slippage, difficult steering, inaccurate spreader positioning, and excessive energy consumption," turning what should be flexible yard operations into clumsy and inefficient struggles. Wuxi ChuncoTech's answer is: A true "mobile backbone" is not "just being able to move," but rather "moving freely and confidently under heavy loads while remaining precise and stable in every stacking operation."
The Yard Giant on Tyres
An RTG crane (full name: Rubber-Tyred Gantry Crane), also known as a rubber-tyred gantry crane or yard crane, shares a similar structure with giant gantry cranes – consisting of a main girder, legs, end beams, and trolley – but the biggest difference is: instead of steel wheels and rails, multiple sets of solid rubber tyres and independent steering mechanisms are installed at the bottom of its legs. This change frees the RTG from the constraints of rails, allowing it to relocate freely within the yard and adjust its position at any time based on operational needs. In terms of span and stacking capacity, a typical RTG covers 6 rows of containers plus one lane, with a stacking height of 5 to 6 tiers – some models even achieving 7-tier stacking.
The core value of an RTG crane lies in this: It is not designed for "ship-to-shore handling," but rather for "efficient yard stacking and flexible transfer." A typical RTG has a lifting capacity of 40 to 50 tons. Through the coordinated action of gantry travel, trolley cross-travel, and spreader hoisting, it can reach every container position within its operating zone. Compared to rail-mounted RMGs, the greatest advantage of the RTG is its flexibility – it can relocate to different yard blocks and adjust its position at any time as yard layouts change. In the design and manufacturing of RTG cranes, Wuxi ChuncoTech takes heavy-load travel drive, multi-mode steering, spreader anti-sway and positioning, and energy saving as its four core technical areas.
Solving the Three "Operational Difficulties"
In the use of RTGs, operators and yard managers are most frustrated by three things: tyre slippage under heavy loads, making travel and steering difficult; excessive spreader swing during high-speed travel and high-tier stacking, causing lengthy alignment times; and high energy consumption, putting pressure on operating costs.
1.Heavy-Load Travel and Anti-Slip Control: The drive wheels of an RTG are prone to slippage on wet surfaces or during heavy-load starts. We use multi-motor independent drive and intelligent torque distribution control, automatically adjusting drive force based on each tyre's real-time adhesion to prevent slipping and veering. The tyres are high-capacity solid rubber tyres, completely eliminating the risk of punctures. Differential locks and anti-slip control systems ensure that even in rainy or snowy weather or on wet surfaces, the RTG maintains smooth starts, uniform travel, and precise braking. For terminals in regions with year-round rain or freezing conditions, optional automatic tyre anti-slip chains or sand spreading devices are available to further enhance traction.
2.Spreader Anti-Sway and Precise Stacking: Stacking accuracy directly affects yard utilization and operational safety. We equip our cranes with an electronic anti-sway system that, through variable frequency speed control and speed curve optimization, controls spreader swing amplitude within ±25 millimeters. Laser or camera-assisted alignment systems display the relative position between the spreader and container corner castings in real time. An optional semi-automatic stacking system is available – the operator simply confirms with one button, and the system automatically completes the entire sequence of lowering, alignment, landing, and twistlock release. For customers seeking higher levels of automation, a fully automatic stacking system is also available, achieving "hands-free" yard operations.
3.Energy Saving and Power Option Selection: RTGs are major energy consumers in container yards. We offer multiple power solutions to suit different customer needs: diesel engine-generator set (flexible but high fuel consumption); diesel-battery hybrid (30% to 40% fuel consumption reduction); lithium battery electric drive (zero emissions, low noise, with quick battery swap capability); cable reel (zero emissions but limited relocation range); and conductor bar (zero emissions, suitable for fixed-lane operations). Customers can select the optimal solution based on their operational intensity, environmental requirements, and relocation needs. For customers with existing diesel RTGs, we also offer diesel-to-electric retrofit services, significantly reducing operating costs and carbon emissions.
From Seaports to Rail Yards: Full-Scene Coverage of RTGs
Wuxi ChuncoTech's RTG cranes are widely used at seaport container yards, inland river port yards, rail container centers, and highway freight hub yards. Compared to RMG cranes, the RTG has rail-free travel, multi-mode steering, and flexible relocation as its core advantages, making it suitable for yards with frequently changing operational zones, irregular yard layouts, and moderate automation requirements. When STS cranes handle "ship-to-shore handling," RMG cranes handle "rail-mounted automated stacking," and RTG cranes handle "flexible mobile yard operations," Wuxi ChuncoTech builds for its customers a complete container logistics equipment system ranging from ship to shore, from shore to yard, from rails to tyres.
Choosing Wuxi ChuncoTech means you receive not just an RTG crane, but a mature solution validated by multiple large yard projects. All our products are mature models already in volume production with highly reliable drive and steering systems. Whether you need diesel-battery hybrid RTGs for a new container yard, zero-emission battery electric RTGs for a green port, or an RTG diesel-to-electric retrofit for an old yard, please visit our website at https://www.chuncotech.com/ to obtain a professional solution for flexible and efficient container yard operations.