Over the past decade, many distribution centers have turned to software tools for automated truck load mapping—also known as load diagramming or load planning. An accurate load map helps DC personnel know where to place each case assigned on a trailer for outbound loads. Multiple stops, trailer compartments, side doors, mixed product rules, axle weight limitations, and customer requirements all factor into the complexity of the load mapping challenge.
When considering a new software solution for load mapping, or simply ways to improve what you are now doing, one or all of these key factors should bear attention:
1. Dynamic Order Volumes
The fact is that no shipping day is exactly like another. So, Monday’s excellent load map may not work so well on Tuesday, or even for the following Monday. An effective load mapping tool should adapt to every day’s changing demands, using logic to find the most efficient blueprint to meet that day’s demand.
2. Varying Equipment Profiles
Most distribution operations use a variety of trailer types and straight trucks. Not only does equipment come in a variety of lengths, but several other critical factors vary as well. Side doors are located in different spots, bulkheads may be fixed or adjustable within a certain range, and overhead structures such as evaporators or door storage may limit capacity in different areas. Load mapping should recognize these various characteristics and build a load plan that fits within these constraints.
3. Visualizing the Load
The most readily understandable way to visualize any given load plan is by displaying key information such as stops and case quantities in a simple grid. The grid is an intuitive format that allows loaders and drivers to immediately see the big picture as well as the details, all at once. But I don’t think I’ve ever seen two diagrams exactly the same. Each warehouse needs to see certain types of information and cares little about other types. So, the contents of the visual diagrams should be flexible enough to show what your operation needs to see.
4. Manual Overrides
Everyone likes a simple one-button answer. But, there are always exceptions such as late orders or a one-time request. It’s essential to have the option to easily move cases or even whole pallets around to meet those needs without slowing down fast-paced operations.
5. Axle Weights
Some warehouse employees seem to have a sixth sense for loading a trailer just right to avoid overloading the axles. However, it’s probably the single hardest thing to do without an automated tool. Overloaded axles incur costly fines or costly reloading labor. Your solution should be able to automatically build loads that avoid overloading an axle, and should automatically recalculate accurate estimates of the axle loadings with each manual change to the diagram.
6. Linking Load Plans to Selection
Optimizing one area of any logistics operation in isolation is a risky endeavor. Ideally, after building a load plan, pallets should be built to match the contents of the diagram. However, too many operations silo the selection task queue in a WMS, missing fuller optimization. In some operations, by selecting product in the correct sequence, pallets can be live-loaded onto the trailer, bypassing the expensive staging operation.
7. Integration with Transportation
Just as load mapping must interface with the selection process on the front-end, it must also integrate with the dispatching and transportation process on the back-end. The load planning process forms a bridge from the warehouse to transportation, connecting two functions that are notorious for their separation. Drivers should refer to load maps not just for stops, but also any special delivery instructions.
8. Flexible Capacities
Does your load mapping tool recognize the maximum capacity for each pallet, which might vary by compartment? Does it allow for a separate set of capacities for high volume loads where product is expected to be hand-stacked above the normal levels in order to meet the requirements of the route? Other load situations require containers with special footprints (e.g., carts, bread trays, or small wood) or certain product types (e.g., totes or ice cream coolers). Some special containers (such as bulk cylinders) remain fixed within the vehicle and are not removed even after its product has been removed—in which case the diagramming algorithm must take into account the fixed container to allow a workable unloading sequence for the remaining stops.
9. Special Customer Requirements
Distribution is a service, and the end customer or delivery point will often have special requirements. Some customers want products loaded on separate pallets so that whole pallets are unloaded at a dock without the driver having to handle individual cases. Your diagramming solution must be able to honor such customer demands.
10. Product Requirements
In addition to customer requirements, certain product types also have special handling considerations. For example, ice cream may need to be packed in coolers, high volume products may be loaded in bulk as full pallets to reduce selection time, and other product types may need to be grouped separately from others, e.g. keeping cleaning and other caustic product separate from foods. In short, load planning is more than assigning a trailer type based on an order’s cube volume. It should not miss the key ingredient of the load map, for fast and accurate loading and unloading of trailers.