Pallets are the workhorses of the packing and shipping industries, and as such they are exposed to a lot of wear and tear. Pallets intended for multiple use have a limited lifetime, during which certain parts of the pallet may need to be repaired and replaced. The ability to predict how many handling cycles a pallet can withstand and what part of the pallet will fail first can help protect the goods and workers they encounter. When a pallet fails, it can threaten the safety of workers as well as cause damage to large quantities of product. Having a good idea of when a pallet will need to come in for repair and when it needs to be retired can prevent these accidents. A durability analysis performed by the Pallet Design System (PDS) provides valuable insight into a pallet’s life including: how many cycles until first repair, what will require repair most frequently, how many cycles until first replacement, what will most likely need to be replaced and how many total cycles in a pallet’s lifetime. These calculations are based on actual warehouse observations, quantitative data, and laboratory measurements, specific to the handling and storage of pallets. Although the PDS durability analysis has had it’s validity tested by the NWPCA it is important to note that a pallet manufacturer has no way of determining the “state of use” from one customer to another.
How Long Will a Pallet Last?
For companies that use multiple-use pallets, understanding the typical life of their pallets is key to budget planning and forecasting as well as preventing accidents in the workplace. A PDS performs a pallet service life analysis, which simulates a series of forces and impacts during each handling cycle to estimate how many cycles a pallet will last. The frequency and severity of the forces and impacts are calculated based on pallet handling observations and data specific to the client. Beyond the design of the pallet, the variables that must be considered are:
- Handling and treatment
- Load duty
- Environment
For example, a stringer pallet that is exposed to average handling and treatment, medium-duty loads and a dry environment may have a predicted service life of nine cycles with three predicted cycles until first repair.
What Repairs Will Be Needed?
During a pallet’s life, it will likely need repair, if not once, but a few times. Some parts of the pallet are subjected to greater forces, mishandling and general wear and tear, than others. These are the areas of a pallet most likely to fail first – needing repair, and in more extreme circumstances, to be replaced. The PDS system can calculate time to first repair and time to first replacement using pallet impact simulations. In most cases, the top lead boards on the pallet will need to be repaired or replaced multiple times before the entire pallet is ready for retirement. These boards receive the brunt force of forklifts during handling, and as a result, wear out the fastest.
In the example above, the PDS analysis shows that the top leadboards and bottom leadboards will have to be repaired after three cycles and replaced after five. They will only be replaced once in the pallet’s lifetime and are the limiting factor in the pallet’s life. The exterior stringers will also need to be repaired after four handling cycles and replaced after nine cycles. Since the life cycle of the pallet is nine cycles, the stingers will not actually be replaced.
The PDS is able to provide a detailed analysis of a pallet’s lifecycle. Using simulations of the forces applied to the pallet, it can predict the repair and replacement schedule of a pallet as well as its overall life expectancy. This information is useful because it enables companies to more accurately predict their pallet expenses and prevent accidents involving pallet failure.
