The art and science of dynamic slotting

Slotting is the process of assigning items to specific pick face locations in order to gain productivity, efficiency and accuracy. Slotting systems are meant to monitor the activity in the pick-zone and make recommendation on when to replenish, what to replenish and where to replenish.

In conventional slotting several attributes like the velocity of the product, order affinity with other products in the warehouse, nature and weight of the products, location dimensions and capacity, distance from the shipping dock, accessibility of the locations are taken into consideration.

Now let us see some of these attributes in detail in order to understand the science behind the slotting process.

Velocity of the product: The more the velocity it is better to place them close to the shipping docks as the pick volume for the product is more

Order Affinity: For example if baseball and bat are ordered simultaneously and hence keeping them side by side reduces the travel time and increases efficiency and productivity. On the other hand, if the products are very similar keeping them separate from each other increases the picking accuracy.

Nature and weight of the products: Heavier items are placed in the beginning of the pick route rather than fragile items in order to avoid damages to the products.

Accessibility of the location: Bulkier items need to be placed in the lower level in order to reduce strains to the arms and the spine.

In conventional slotting the time horizon is fairly long between each slotting cycle say every year the company might want to re-slot its locations. Most of the times operations are stopped and re-slotting plan gets executed independently of the orders in the system.

In dynamic slotting, the time horizons are very short and the pick face realignments are dynamic in nature. It runs with the assumption of the levels of inventory in each of the existing slots is known and when they will be picked to zero is also known. That means the demand is known well in advance and the order or wave planning happens much ahead of actual picking time. In dynamic slotting the number of pick-faces per item is also dynamic in nature depending on the demand and hence more efficiency is gained compared to conventional static slotting.

An illustration with simple order demand attribute is given below

While the above factors contribute to the science of slotting, deciding on what are the factors that needs to be considered is an art. Certain factors have more weightage over others in a specific warehouse scenario. Sometimes it is simply may not be possible to incorporate a parameter at the product level as it tend to become too complex and fussy. In such cases factors can be considered at part family levels. Many times practice makes perfection. The best way is to start implementing the factors' contributions incrementally in the slotting plan. Thus having a successful dynamic slotting plan is an art as well as a science.

When to migrate to newer WMS

Change is the constant thing in the world. At times our ROI is being held up by outdated technology and makes us less competitive. Customers and suppliers upgrade to new technology as they also face these challenges. Changing technology products comes with a cost. The benefits that will be realized by the change must be substantiated. So when to change your existing warehouse management application to a new WMS is an important question before every warehouse manager.

It all starts with technology out-date.  Newer technology keeps coming day by day. This may range from RF based picking to voice picking to RFID tags. As a result companies which adopt these technologies gain benefit from various quarters including operational efficiency. They tend to stay competitive in the market.

Technology out-dates lead to unrealistic total cost of ownership. This is mainly driven by increased cost of support and maintenance of the applications, reduced return on investments due to operational efficiency lag.Too many high priority issues appear in the application leading to higher downtime and less productivity.

Other parties like suppliers and customers also face these issues with technology out-date.  To stay competitive they also upgrade to newer technologies which requires standardization in operational procedures and system policies. Customers thus enforce the company to migrate to latest technology products which offers standardized operational procedures, resilient architecture and optimizes the productivity of the warehouse personnel.

Whether we like it or not, we are thus enforced to migrate to newer technology whenever the total cost of ownership exceeds and there is an upward trend in the support and maintenance costs.

RedPrairie WMS and Mobile phone industry

Mobile phone industry envisages ever changing business needs more rapidly than any other industry. People upgrade to new cell phones not because their old phones were broken, but because advances in technology had made them obsolete. Technology advancements keep the production / assembly process getting changed quite frequently. As a result production warehouses of mobile phones need dynamic workflow management to cater to this unique and most vital characteristic of this industry. WMS Products which offer dynamic configuration of workflows using multiple exit points are the most preferred. RedPrairie’s dynamic workflow configurations which are easy to make at various exit points is highly useful to the warehouse operations. For example when a battery model gets changed and the labels on the battery has to be verified post identification, a workflow with exit point as post-identify can easily be configured to instruct the workforce to validate the labels on the batteries before being put away into the storage shelves.

Companies are forced to source from multiple sourcing points and manufacture at globally distributed warehouses before being shipped to the customer. Improving flexibility in the supply chain processes is the key in this industry as makes and models keep changing quite rapidly. This requires warehouse management process to be highly parameterized and controls and checks can be dynamically changed. RedPrairie’s parameterized policy frame work enables and caters to this need so well that many other products miss in this industry. System policies and frameworks of various operational policies enable it as the right choice for the mobile phone manufacturing warehouses.

Running a globally distributed supply chain needs high visibility of inventory levels to various participants in the supply chain such as suppliers and customers. RedPrairie’s web enabled reporting features ensures high web visibility and hence fits as the right choice for this industry. The dashboards and reports both standard and customized can give a great visibility on the inventory levels to the suppliers. Vendor managed inventory supply chain thus gets equipped with right systems and tools.

Many of the mobile warehouses are custom bonded warehouses as they have been set up in special economic zones to gain tax benefit advantages. This results in a need for sharing the inventory detail with the customs department as a matter of regional legal compliance. RedPrairie’s DLx integrator caters to the easy and trouble free integration needs so well that many customers rely on it than any other product in this industry.

This industry calls for a list picking. For example, to ship out one mobile phone unit for assembly, one handset, one battery, one earphone and one user guide needs to be picked and dispatched for light assembly. Thus married product picking and list picking is vital in this industry. RedPrairie enables these features smoother than any other product in the market.

Serialized inventory along with serial number merging operation is often required here. Suppose a vendor has a particular serial number and the other spare part as a different serial number, when assembled, serial numbers might need to be merged to get unique serial number. RedPrairie’s merge serial operation is a boon for this requirement.

Functional features that enable RP as a right choice for mobile phone industry

Apart from its ability to define workflows specific to a supplier or a part, its ability in parcel manifesting is commendable. It has integrated, 3PL specific parcel manifesting features for the leading logistics providers and hence a ready to use parcel manifesting application is inbuilt within it. It can also be easily integrated to external parcel manifesting applications if the unique manifesting needs call for them.

With high parameterized configuration capabilities and other key features that are unique to RP which are vital for the mobile phone industry, RP as the preferred choice of WMS for this industry is here to stay.