Product storage is an essential part of warehouse operations. If there were a way to store products that will assure better efficiency, wouldn’t you apply it?
One storage method that helps to ensure efficiency of operation is slotting. This method of storing focuses on the popularity of the product, its measurements, its weight, grouping with other products, and other fundamentals to create the most ideal warehouse layout. The purpose is to ensure that picking and replacement of products is done faster, easier, and more proficiently.
The concept behind slotting is to assign each product a specific space within the warehouse that solves all of these issues. For example, you place the most ordered products closest to checkout and the least ordered products further away.
Setting up such a warehouse can be a daunting task. However, there is warehouse management software or standalone software that can guide you along.
Advantages Of Slotting
Successful slotting means that you have an efficient use of space, less handling, and shorter travel times for pickers. It is said that efficient slotting can save a warehouse up to 20 percent of its labor costs. When you consider that order picking commonly require between 40 percent and 60 percent of man-hours, then you can see the possible savings.
A warehouse plan that incorporates a good slotting design offers a plethora of benefits.
When each product is in its proper place, there is less clutter and better organization. This results in more available space because space is being used more efficiently.
It also means that workers are not wasting time roaming all over the warehouse during their picking, thus reducing travel time. When products are slotted properly, picking as well as replenishing stock takes less time.
A good slotting plan assures more visibility and reduces errors. Pickers can see quickly where products are stored within a zone and know what products are close by.
A slotting strategy also prevents bottlenecks and wait times on the warehouse floor. Pickers won’t be getting in each other’s way.
It also reduces product damage by minimizing traffic in the aisles and touches of products.
Gathering Slotting Data
Creating a strategy of slotting requires the gathering of data that assists in determining the proper set up. It is essential that you collect information on each of your SKUs. The data you will need to create a slotting plan include:
• Whether one item is being picked, a number of the item is being picked, a case is being picked, or a full pallet is being picked.
• Whether the item is picked from a pallet rack, shelf, or carton.
• The cube size and weight of the item.
• The velocity (or popularity) of the product.
• Seasonal variations of the popularity of the product.
• Special storage requirements.
• The products that are commonly ordered together most often.
How The Item Is Being Picked
If a full pallet is picked, then a forklift will be required. One worker alone can pick a single item. So, the best strategy is to store pallets independently from cases and broken cases. This prevents forklifts from getting in the way of individual workers who are picking a single product.
The level of a storage shelf a product is located will also determine whether a forklift, pallet jack, cart, or other equipment will be necessary for the pick. Pickers should know what kind of equipment is necessary to make a pick by the area in which the product is stored.
Also keep in mind that there is a so-called “sweet spot” in which it is easier for a picker to see and reach for an item. The area is between the worker’s chest and knees. The highest velocity or most popular items should be in this vicinity on shelves. Slower moving items should be out of the way. The heaviest items should be low and as close to the floor as possible.
Cube Size And Weight Of The Product
What level of a shelf or what storage medium to use should be based on the size and weight of the product. Full cases and palletized items are commonly placed in select racks. Broken cases usually go on shelves.
An item’s velocity or popularity determines where products are stored in relation to the checkout point. But it is suggested that large or heavy items be placed closer to checkout because they are more difficult to handle and thus take more time to pick. Your strategy of slotting should also take into account the cubic velocity or a product’s average quantity ordered over time, the product’s dimensions, and the level on which the item is stored.
Velocity Of Products
When developing a slotting strategy, consider this. “The fast moving SKUs stay accessible and the slow-movers stay out of the way.” So place the faster moving (or most popular) items closer to the down-forward picking area. Such a plan will minimize travel time for pickers.
Discovering the fastest moving items in your warehouse can be done by monitoring its number of orders over a specific time frame. That can be 30 days, but a shorter or longer time frame may work better for your operation. Many warehouses have used a timer period as short as only 12 days.
Once you determine the fastest moving items, list them by the number of line orders. The items with the most line orders are the top 50 percent and categorized as “A”, the next 25 percent is categorized as “B”, and the last 25 percent should be designated “C.” Items that did not make the list because they were not ordered within the time frame, can be designated “D.”
Arrange these items in groups based on their designation. The items designated as “A” should be closest to the down-forward picking area. Items designated as “D,” should be further away.
Efficiency is improved when you can predict the order velocity of an item for the future. If an item becomes more popular in a particular season or period of a calendar year, then it should be closer to the forward picking area.
Special Storage Requirements
When developing a slotting plan you also need to keep certain storage needs of products in mind. Products should be grouped together into zones determined on their storage needs. For example:
• High security products need to be congregated in a secure caged zone.
• Products that have certain temperature requirements should be stored in temperature-controlled areas.
• Items that are toxic should be isolated in a separate area of the warehouse.
Gather items together that are more frequently ordered together. For example, razors should be stored with replacement blades and shaving cream. Gift-wrap is naturally combined with ribbons and gift bows. Books on the same topic can be grouped together, etc.
Keep space open in each zone or slot for replacement inventory. Many warehouses assure that there is enough space in each zone or slot to contain a month’s worth of inventory replacements.