| Written by Mark Buzinkay
The current market situation of dwindling margins and tightening delivery windows has increased complexity in container terminal planning & scheduling processes. Therefore, the efficient use of resources is a top priority. An advanced planning & scheduling solution holds a substantial cost savings potential for planning departments while also boosting delivery reliability and flexibility.
Eventually, this supports a healthier bottom line and improves competitive advantage. As container terminal activities are integral parts of the supply chain, they must perform. This is a daily challenge, both in terms of economics and in terms of planning. Performance is closely measured to minimise turnaround times and vessel delays.
Container terminal activities are tough to manage since the various services involved in the loading/unloading of vessels are interdependent. For example, unmooring can only be started when all other services are finished; ships can't share the same parts of a berth, and some container types (e.g., hazardous types) cannot be stored close to other container types.
CONTAINER TERMINAL PLANNING: KEY PROCESSES
If we look at a container terminal as a system of material flow, it can be split up into three sections or areas:
- The gate and landside operations where containers are handled by trucks and trains.
- The yardside where full and empty containers are stored temporarily.
- The quayside is where containers are loaded and unloaded on and off vessels.
Mainly, there are two operations visible in container terminals: discharging and loading. The discharging process begins when ships arrive at the port. They are moored at the berth (quayside), and import and transhipment containers are discharged by ship-to-shore cranes and loaded onto internal container handling equipment. The containers are ferried and stored in the appropriate yard locations based on the terminal's storage plan. Yard or transfer cranes lift the containers from the truck and stack them according to the yard plan. Import containers for primarily local consumption are retrieved by haulage companies and moved out of the terminal via the terminal gates. Transhipment containers are stored in the yard for a while before loading onto the assigned (loading) vessel.
The loading process begins at the gate, where external trucks haul the export containers to the terminal via the gate. Containers are stored in the yard until it's time for loading. It is best practice to ensure that the export containers are evenly distributed in the yard to avoid bottlenecks will appear during the loading operation. The aim is to spread volume across the yard cranes to ensure maximum productivity of each crane. Next, yard cranes remove the containers from the stacks and place them on internal vehicles, which will subsequently transfer them to the quayside. Finally, the containers are loaded onto the ship by ship-to-shore cranes according to the stowage instruction given by the shipping line.
CONTAINER TERMINAL PLANNING: KEY COMPONENTS
The key components in discharging and loading operations are (1) vessels and external transport (trucks, rail), (2) container terminal infrastructure like berth availability, yard, handling equipment (such as STS cranes, straddle carriers, automated stacking cranes), internal transport vehicles and (3) labour.
Container terminal planning happens along different time frames. Long-term strategic decisions deal with the layout of the container terminal and investment in infrastructure and equipment. They will define the overall performance and capacity of a container terminal. Similarly, tactical, months-to-week decisions support strategic decisions and optimise strategic choices. Operational decisions execute the above described two key processes. In the following, we will focus on operational decisions when planning container terminal operations (learn more about the challenges of terminal automation).
The most significant aspects of operational planning of a container terminal include berth, yard, equipment (includes vessels, cranes, and vehicles) and workforce planning.
In general, planning and (detailed) scheduling of container terminal processes are characterised by complex business logic and numerous limitations as well as production disruptions (e.g., equipment breakdown), equipment maintenance and vessel schedule unreliability. This creates the need to conduct "What-if" scenarios to design different planning outcomes, given the unanticipated events that planners encounter daily. As one can see, there are many elements to effective and efficient container terminal planning.
CONTAINER TERMINAL PLANNING: KEY AREAS
Berth planning
Berth planning is the first stage of planning. First, berth planners need to assign a berth for an incoming vessel. The vessel will occupy the berth during its port stay. Second, the berth planner needs to plan the berth near its yard locations where most containers for this specific vessel are located to minimise the distance travelled by the trucks. Third, the berth planners use tools such as Gantt charts for efficient berth allocation and planning. Another aspect of berth planning is tides, as there are significant restrictions regarding large boats and low tides (e.g. Hamburg).
Vessel and crane planning
Before a vessel arrives, shipping lines share the stowage plan for all ports of a vessel's rotation to the terminal via Electronic Data Interchange (EDI). The terminal's ship planner uses the stowage instruction to plan the loading and discharging sequence of containers to/from the ship while preserving the ship's stability. Although the main objective of stowage planning is to maintain the ship's stability, a good ship planner should consider both the ship's sections to be planned and the container locations in the yard to reduce the number of rehandles in the yard. The objective is to maximise the efficiency of yard cranes and ship-to-shore cranes.
Often, the vessel planner must adapt the stowage plan prepared in advance due to "late-minute" changes (e.g. because of late arrival, a berth may have to be re-assigned). Exceptions during ship loading are almost usual (for instance, a container changes its next port of call and must be re-assigned to a new location). Such problems should be addressed on the spot to mitigate the impact on the daily operation. For example, if a ship-to-shore crane breaks down or congestion in the yard occurs during ship operation, the loading or unloading sequence of containers may change. Hence, ship planning in practice is a dynamic process which requires sound coordination between the quay and the yard with the intention that the containers from the yard arrive at the quay in the correct sequence, ready for loading.
Yard planning
The yard planners decide the container locations in the yard (yard blocks) to transport them efficiently between the yard, gate and quay. At the detailed level, the container storage and stacking objective is to minimise the vessel port stay, operational cost and the number of rehandles as well as service outside trucks as efficiently as possible. Continue reading about container yard operations at TTI Algeciras.
Vehicles planning
Yard planners must efficiently schedule the operators to terminal vehicles to minimise the workforce required while satisfying the demand. During operations, the yard planners need to decide how to assign/ schedule containers to terminal vehicles to minimise the number of vehicles required to carry out specific jobs or reduce the distance travelled. They also need to schedule yard cranes and assign the jobs to lower the total completion time of a given set of assignments. It is essential to plan the working schedule to reduce unproductive moves efficiently.
At the intermodal transport level, the managers determine the daily working schedules of the operators as well as the schedules/ routes for each of the combined modes of transport to achieve on-time delivery at the minimum cost. The objective of intermodal transport is to utilise each respective mode of transport's advantages to make the transportation process as efficient and economical as possible.
Workforce scheduling and planning
As even a fully automated container terminal can't function without people, workforce planning is necessary. Workforce planners must provide an efficient, cyclical workforce schedule for hundreds, sometimes thousands of workers 24 hours a day, 7 days a week. It must be aligned with vehicles, crane and vessel planning schedules but also considers exception handling, maintenance, external workers, and on-call duty staff.
TAKEAWAY
Container terminals form a vital gateway in the transport chain for the shipment of cargo containers. To handle the enormous amount of throughput, the advancement of information technology has played a crucial role in automating processes and transferring data seamlessly between the shipping lines and the terminal operators (learn more about port automation challenges). The essential objective for a container terminal is to shorten the vessel port stay as the vessels are most profitable while at sea.
Unfortunately, the experience of the operators and the basic rules of thumb for a complex terminal operation does not always yield a good plan. Therefore, terminal managers are now looking at combining information technology with optimisation techniques to produce feasible plans for storage space allocation, resource scheduling, berth allocation etc.
Container terminal operations planning software supports managing the planning process's complexity and helps minimise vessel turnaround time and improve terminal efficiency.
Learn more about port automation in our collection of articles and whitepapers!
