Slotting your inventory is more than just making sure that heavy items are not located on the highest shelf or fast movers in the back of the warehouse. It’s meant to evaluate the size, the storage media, the mix, and the velocity of product being stored in the distribution center in order to maximize productivity, order accuracy, and customer service.
There are two kinds of slotting: manual and software-based. If your operations are dealing with a diverse product mix or highly seasonable items, software-based slotting may be worth examining. In fact, most operations selling more than 5,000 SKUs should be using slotting software, which is typically found as part of your warehouse management system (WMS). If you’re a smaller operation, you can get along quite nicely using spreadsheets. Software-based slotting can cost about $150,000 for licensing and configuration.
If it’s not a part of your WMS, slotting software must be integrated to your DC operational systems, such as your labor management systems. This enables the slotting plan to be a natural complement to normal DC operations such as replenishment and put-away. Inventory managers would then be less likely to delay reslotting, since the onerous task of shutting down the DC to execute the reslot could be avoided, and incremental ROI could be achieved on a regular basis.
And slotting programs live and die by data accuracy. “The integrity of the SKU data is essential,” says Ron Grove, vice president of facility design and material handling engineering for Long Grove, IL-based supply chain consultancy Tom Zosel Associates. Be sure the documents are verified and accurate. For instance, if the weight of a given item is off because the decimal point is in the wrong place, you could end up having hefty items stored in an ergonomically incorrect location.
To ensure the best results, you must measure case dimensions and quantities for each category. Be sure to capture the weight of each product as well as adding other special instructions that go along with the SKU listing.
Be prepared to do some manual intervention. You can expect to override about 2% of your products, according to Grove. These could in the form of an oddly shaped SKU, such as a long broom handle, or an inaccuracy because of bad data.