Put away is the process of moving items from one place to another, inside a warehouse. It may include different items (one unit of a package or several units, whether in a container or not).
Why is it so important?
- You have 100 orders to fulfill until the end of the day.
- On average, each order has 2 items to pick (on a total of 200).
- Your warehouse is around 1.000 sqr meters, with around 30 aisles and 1.800 shelves.
Scenario A: You have the items spread throughout the warehouse, making the operator to walk through 15 aisles to pick all the items.
Scenario B: You have the items close together, making the operator to walk through 10 aisles to pick all the items.
Question: How long will it take to fulfill the orders in each scenario? Which scenario takes less time to accomplish?
That’s a no brainer, right? It is the scenario B!
Now, the question you need to ask yourself is: what changes do I need to accomplish in my warehouse in order to minimize the number of aisles my operators need to walk through to deliver my orders? In other words, how do I minimize the flow of goods and people?
Another benefit of the put away process is to optimize space.
Depending on the type of business you have, you may deal with many SKUs (Stock Keeping Units). You don’t work with all SKUs at the same time, although you have them in your portfolio, thus you have to be able to store them when they arrive in the warehouse. Moreover, each SKU may be different from another. Whether in size or weight.
Hence, a good put away allows you to efficiently deal with this diverse reality and allow to have space whenever needed.
Analyze products’ characteristics
There are several ways of organizing a warehouse. It may be dynamic as well, meaning the way you do your put away may change over time.
Before deciding which is the best for your business, you should analyze your products’ characteristics: dimension, weight, type of product (chemicals, controlled temperature, etc), the way of shipping (single or in bulk, as a pack with any other product, etc), frequency of shipping, etc.
Whether the products you work with are more homogeneous or less, you may have to adequate your storage facilities in order to store these items in the right place. For instance, there are products that can only be moved apart by someone with a special authoroty. There are products, due to its chemical composition, cannot be stored near certain materials. Others are so heavy that can only be stored near the ground or on special racks. I think you got it!
In conclusion, once you have done this analysis you will be able to define how should the put away be done as well as if your warehouse needs a change in the layout.
Reserve vs Picking zones
The smaller the area to cover, the lower the average time to fulfill an order, right?
It is important to decide if there will be a Reserve zone and a Picking zone or not. If so, the next step is to determine, to each product, how many units will be placed in the Picking zone.
The rest will have to be put away to reserve. Whenever the Picking zone gets low stock, a replenishment from de Reserve zone must take place.
Know more about warehouse zoning, here.
Dynamic vs Fixed locations
A product can be stored in different places at the same time (dynamic) or to have a fixed location to be in (fixed). This decision relates to its characteristics, as said before. After deciding the zones you need to have in the warehouse, how will the locations work must be considered.
Storage assignment rules
Despite there’s countless ways of assigning products to locations, we are going to describe five that are frequently used:
- Random Storage: the product will be given an empty location, randomly picked. This method results in high space utilization at the expense of increased travel distance. This should only be used under a computer controlled environment.
- Closest Open Location Storage: the product will be stored in the first empty location the operator can find. Usually, this method leads to a warehouse where racks are full around the receiving zone and more empty towards the back.
- Dedicated Storage: the Dedicated Storage method is when a product has a fixed location and it is always stored in the same place. A disadvantage of this method is that the location will be unused even if there is no stock of the product. Plus, since you should reserve the amount of space needed to store the maximium inventory level, every time the stock level of the product is lower than the maximum, you will be wasting storage space. An advantage of this method is that operators get familiar with the product locations. However, if they are using a warehouse management software, the system will tell them where to go (making this a not so great advantage).
- Full Turnover Storage: the turnover rate is what determines where the product is placed. The highest the rate, the closest to the easiest accessible locations, usually near the depot. Products with lower turnover rate are stored in the least accessible locations. This method has the advantage of minimizing the overall traveled distance in the order fulfillment process.
- Class Based Storage: this method is kind of a mix up of some of the methods explained so far. Basically it assumes products are divided into classes, according to one or several criterias. For example, using Pareto’s method, the idea is that the fastest moving class has only about 15% of the products stored but contributes to about 85% of the turnover. Each class is assigned to a dedicated area of the warehouse and the storage within an area is random. Usually, the products within the fastest class are called A-products. The next fastest moving cluster of products are called B-products, and so on. The number of classes is often restricted to three. However, in some cases, it makes sense to have more, if it represents additional gains in travel times.
The put away process is not a simple thing in terms of design and deciding what is the best way of doing it. In fact, it is quite complex!
But it is also key for (1) an operation that is simpler, faster, with less waste, as well as (2) an optimized storage space.
When deciding which process to adopt, remember to:
- Analyze products’ characteristics
- Analyze which storage zones your warehouse shall have
- Decide on whether to use fixed or dynamic locations
- Decide on the storage assignment rules to adopt