In North America, particularly in the United States, the use of chassis for moving and temporarily storing containers within terminal premises is a prevalent practice. This method, known as "wheeled operations," involves placing containers on chassis to facilitate efficient intra-terminal transport and short-term storage. While the exact number of container terminals employing this method is not readily available, it is widely adopted across many facilities due to its operational advantages.
Wheeled operations offer several benefits, including reduced container handling, minimized lifting equipment requirements, and expedited truck turnaround times. However, they also demand significant terminal space to accommodate both the containers and the chassis. This spatial requirement can limit storage density compared to grounded operations, where containers are stacked directly on the ground. Consequently, terminals with ample space often prefer wheeled operations, while those with spatial constraints may opt for grounded or mixed storage strategies.
Factors such as terminal size, container throughput volume, and specific operational needs influence the choice between wheeled and grounded operations.
In practice, many terminals implement a hybrid approach, utilizing wheeled storage for certain container types—such as refrigerated or hazardous materials—that require easy access and grounded storage for others to optimize space utilization.
It's important to note that wheeled operations are more prevalent in North America than in other regions. This is due to historical practices, equipment availability, and the operational preferences of North American ports and terminals. In contrast, terminals in regions like Europe and Asia predominantly use grounded operations, relying on stacking equipment such as rubber-tired gantry cranes (RTGs) or straddle carriers to manage container storage.
Wheeled operations typically rely heavily on manual processes, analogue systems, and yard personnel's expertise to maintain efficiency. This approach involves a combination of fixed protocols, scheduled data updates, and real-time communication among staff to manage container movement effectively.
When a container arrives at the terminal, either by truck, rail, or ship, its details are logged manually or entered into a digital system (like a TOS) by gate clerks. This initial information includes the container's size, type, and contents, as well as its final destination or its next transit point. The container is then assigned a chassis, which serves as its temporary parking spot. Yard personnel, often referred to as "yard checkers," physically assign parking spots based on their knowledge of yard availability and pre-determined allocation rules. The chassis provides flexibility in relocating containers without the need for additional handling equipment, simplifying short-term storage and movement within the terminal.
The yard is typically divided into distinct zones for imports, exports, empties, and special categories like refrigerated containers. Allocation of these zones is based on operational experience and planning. For example, export containers may be parked closer to the quay cranes for faster loading, while import containers are placed further away to allow more time for truck pick-ups. This arrangement reduces congestion and minimizes unnecessary moves. In the absence of digital tracking, yard supervisors rely on physical markers such as numbered lanes or colour-coded chassis to identify where containers are parked. These markers are maintained and updated manually, often through physical inspections conducted at regular intervals.
Communication among yard staff is primarily conducted via radios or phones. When a container needs to be moved, equipment operators receive verbal instructions from a dispatcher, who coordinates tasks based on paper schedules or spreadsheets. Dispatchers must rely on memory, notes, the TOS, or periodic updates from yard checkers to know which spots are free or occupied. This system, while functional, can lead to delays and occasional errors if communication breaks down or if a spot is inaccurately reported as available.
At shift changes or other scheduled times, yard checkers perform physical walkthroughs of the yard to verify and reconcile actual container positions with the records kept in the terminal office. This ensures that the yard map remains relatively accurate, although it always lags behind real-time conditions. Any discrepancies identified during these checks are updated manually in the records. This process can be labour-intensive, requiring a significant amount of coordination and time, particularly in larger terminals with high container volumes.
To mitigate inefficiencies, many analog yards rely on strict operational rules to streamline processes. For instance, drivers may follow fixed routes to avoid congestion, and containers may be assigned to the nearest available spot rather than the most optimal one. Similarly, zones may be allocated on a "first come, first served" basis, simplifying planning but limiting flexibility in adapting to real-time changes. In this context, pre-determined workflows play a critical role in maintaining order and predictability.
While this manual approach allows the terminal to function, it introduces several limitations. The lack of real-time data makes it difficult to optimize operations dynamically, often leading to bottlenecks during peak periods. Miscommunication and human error are common risks, resulting in misplaced containers or inefficient equipment use. Additionally, manual logging and reconciliation are time-consuming, which reduces overall throughput and increases labour costs.
Despite these challenges, such a system can still manage container flow effectively in smaller terminals or those with lower traffic volumes. The success of this approach depends heavily on the experience and diligence of the yard personnel, as well as the robustness of the established manual processes. However, as container volumes grow and operational demands increase, the limitations of analogue yard management often necessitate a transition to digital systems for greater efficiency and scalability.
A yard management system (YMS) operates as the central coordination tool in a container terminal, ensuring efficient movement, placement, and retrieval of containers. It integrates data from multiple sources, such as gate systems, terminal operating systems (TOS), and container tracking technologies, to provide a real-time view of the yard's layout and inventory. This comprehensive visibility allows the YMS to allocate containers to specific spots in the yard based on predefined criteria and dynamic operational needs.
When a container arrives at the terminal, the YMS processes its details, including its size, type, contents, and destination, to determine the most suitable location in the yard. These allocations are influenced by proximity to loading or unloading equipment, container priority, and yard congestion levels. For example, export containers may be assigned spots closer to the quay cranes for quicker access during vessel loading. In contrast, import containers may be placed in areas convenient for truck pickup.
The system uses advanced algorithms to optimize yard space and minimize travel distances for container-handling equipment. It considers variables such as container weight, stacking limitations, and operational workflows to allocate parking spots efficiently. For instance, refrigerated containers requiring power connections may be directed to specific zones with reefer plug access. Additionally, hazardous materials might be segregated into designated areas to meet safety regulations.
TOS like Navis N4, Tideworks, Konecrane TOS, and others include Yard Management in their TOS features.
Real-time tracking of container movements is integral to the YMS's functionality. Containers equipped with RFID tags, GPS devices, or barcodes are continuously monitored as they are moved by terminal equipment like straddle carriers or reach stackers. The YMS updates its digital yard map dynamically, ensuring accurate location data. This real-time capability reduces the risk of misplaced containers and allows for swift adjustments in response to operational changes, such as vessel delays or equipment breakdowns.
The YMS automates task assignments to equipment operators, further enhancing efficiency. For example, when a container needs to be moved from a parking spot to a ship, the system identifies the closest available equipment, calculates the optimal route, and dispatches the task directly to the operator's terminal or device. This minimizes idle time and maximizes the productivity of yard assets.
The YMS also facilitates proactive yard planning by analyzing historical data and predicting future demand. Terminal operators can plan for peak periods by adjusting container allocation strategies or preemptively reorganizing yard layouts. This predictive capability helps reduce bottlenecks and ensures smooth terminal operations.
In summary, a yard management system operates by integrating real-time data, applying optimization algorithms, and automating task assignments to manage the movement and allocation of containers in the yard. It ensures that containers are placed in optimal locations, equipment usage is efficient, and the overall terminal operations remain seamless and adaptable to dynamic conditions.
The time saved per container move when using a fully digital yard management system compared to an analogue one can be significant, as digital systems eliminate many inefficiencies inherent in manual processes. In an analogue yard, a single container move can take approximately 10 to 15 minutes or more, depending on the time required for manual container identification, verbal communication delays, and reliance on physical yard checks. These inefficiencies arise because information about container locations and parking spot availability is often outdated, and equipment operators must rely on manual instructions that may not reflect real-time conditions.
In contrast, a fully digital yard management system reduces the time for each container move to an average of 3 to 8 minutes. This improvement is achieved through real-time container tracking, automated task assignments, and optimized routing of equipment. A digital system eliminates the need for yard personnel to manually search for containers, as every container's exact location is always available. Additionally, the automation of task assignments ensures that equipment is dispatched promptly and movements are coordinated efficiently to avoid delays caused by human error or miscommunication (see also: Terminal automation and what to look for).
On average, this translates to a time savings of 5 to 10 minutes per container move, representing a reduction of 30–70% in handling time. For a terminal handling thousands of container moves per day, the cumulative effect of this efficiency is substantial, allowing for increased throughput, much higher productivity, and minimized equipment idle time. The precise savings may vary depending on the yard's size, layout, and operational complexity, but the overall reduction in time is consistently significant, demonstrating the transformative impact of digital yard management systems on terminal operations.
Container Identification:
Task Dispatching:
Route Optimization:
Data Recording and Updates:
Transitioning from an analogue to a digital yard management solution requires careful planning and phased implementation to minimize disruptions to operations. It involves upgrading processes, integrating technology, and ensuring the yard is equipped to provide real-time data input.
The first step in transitioning to a digital YMS is assessing the current state of operations and identifying inefficiencies in the analogue system. This involves mapping out workflows, container handling processes, and yard layouts. Once this baseline is established, a clear roadmap for digital transformation can be created.
The transition typically begins with the selection of a YMS tailored to the terminal's specific needs. Choosing a system that integrates seamlessly with existing terminal operating systems (TOS) and supports real-time tracking, task automation, and data analytics is essential. Many terminals opt for scalable solutions that can be implemented in phases, allowing for incremental adjustments.
A phased approach usually starts with digitizing key operations such as container tracking and inventory management. This involves training personnel to use the new software and ensuring that existing records are accurately digitized. Simultaneously, infrastructure upgrades, such as installing wireless networks or yard-wide connectivity, are essential to enable real-time communication between equipment and the YMS.
Once the initial digital systems are operational, the focus shifts to integrating automated task assignments and real-time location tracking. Yard personnel and equipment operators must be trained to work with the system's interfaces, such as handheld devices or in-cab monitors. Gradual implementation allows teams to adapt while avoiding operational disruptions.
To enable real-time data input from chassis, they must be outfitted with technology that allows seamless integration with the YMS. The process includes the following key steps:
What role do chassis play in container terminal operations, and why are they commonly used in North America?
Chassis serve as essential tools for moving and temporarily storing containers within terminal premises. In North America, they are widely used due to their flexibility and efficiency in enabling "wheeled operations," where containers remain on chassis instead of being stacked. This approach reduces the need for additional handling equipment, expedites container movement, and facilitates quicker truck turnarounds. However, wheeled operations demand significant yard space and are best suited for terminals with ample capacity and moderate-to-high container volumes.
How does a yard management system (YMS) integrate with real-time technologies to improve efficiency?
A YMS leverages technologies such as Real-Time Location Systems (RTLS) and RFID to monitor and manage the movement of containers and chassis. RTLS tracks the exact location of chassis using GPS, radio frequencies, or visual markers, while RFID tags provide unique identifiers for each chassis or container. These technologies feed real-time data into the YMS, ensuring precise allocation of parking spots, dynamic task assignments, and optimized equipment routing. The result is reduced handling time, improved accuracy, and 24/7 operational visibility, enabling seamless terminal operations.
Adopting a digital yard management system (YMS) transforms container terminal operations by providing real-time visibility, automation, and efficiency. Unlike analogue processes that rely on manual updates and static workflows, a digital YMS integrates technologies like RFID, RTLS, and IoT sensors to streamline container tracking, optimize equipment use, and reduce handling times. The result is faster operations, fewer errors, and increased throughput. For terminals utilizing chassis-based operations, digital tools enhance yard space management and enable 24/7 monitoring. By transitioning to a digital system, terminals not only address current inefficiencies but also future-proof their operations against growing container volumes and industry demands.
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Sources:
(1) https://www.intelligentcargosystems.com/academy/chassis-operations
(2) https://www.freightwaves.com/news/qa-us-container-chassis-industry-still-finding-itself
(3) https://www.ajot.com/insights/full/the-evolution-of-container-chassis-provisioning-in-the-us