Can manual warehouse operations be ERP based? If so, what problems can arise?

Yes, manual warehouse operations can be ERP based; however, a variety of different problems can arise in these situations, particularly in large warehouse environments. For instance, when the lead or the manager uses printed paperwork to determine picking schedules, it can be difficult to keep all of the data straight and pages may get lost or misplaced along the way. Overstocks can also be problematic.

When a receiver cannot fit all of a product in one location, they need to find another place to store the remainder. If the location information or the quantity that was put in each location is wrong, or written down incorrectly or illegibly, then problems can arise. Since ERP does not offer real-time transaction data, any changes to what is in storage—either because of overstocks or picking—are not accounted for in real-time.

How does ERP handle batch picking, zone picking, and wave picking?

ERPs can have difficulty handling complex picking processes. For example, when there are waves, the first bundle of orders is generally picked and distributed first, before the second wave comes. However, in an ERP-based system, the information is not recorded in real-time. In many cases there is an operator sitting at a desk recording data on every order. That means there are two people—the picker and the person entering the data—involved with each order, and the warehouse manager may not be sure who, if either, is correct. If the picker is supposed to pick 10, but mistakenly only picked nine, but the paperwork says 10, the data entry person enters it as 10. The inventory won’t reconcile, and the customer is shorted. On the other hand, if the picker mistakenly picks 11 instead of 10, the warehouse loses money.

What is slotting and how is it associated with picking speed?

Slotting is the practical application of a statistical analysis for the SKU/product base in a warehouse distribution center or manufacturing facility. It consists of reviewing and analyzing the velocity or movement of items and associated cubic storage movement of those items relative to the other items. The goal is to determine optimal locations to store items and also make decisions about optimized automation systems to store and manage those items. Primarily, slotting improves labor, travel time and automation efficiency. The secondary by-product improvement is space utilization. A slotting analysis can help determine if a business is out of space or consuming too much space. If a business slots correctly and automates correctly, the footprint can often be significantly reduced.

A slotting analysis is based on the cubic dimensions of items, as well as their current and projected velocity. Velocity equates to the requisite travel time for an operator to pick the item over a given period of time. That means that the velocity of an item picked 1,000 times a month is much higher than the velocity of an item picked once a month. Velocity directly correlates to operator labor and travel time either in a non-automated environment or in an automated environment. It could be the wait or dwell time of the automation equipment for that particular item. Conducting a slotting analysis and making decisions about how to optimally slot items in the facility improves productivity substantially. Slotting analysis helps determine what type of automation equipment to use and generates the underlying ROI for re-slotting and/or automating the storage of any given set of SKUs or products.

The average warehouse associate spends 60% of their time traveling. In a warehouse that is properly slotted, travel time can be significantly reduced and that, in turn, lowers labor costs. Slotting can also increase the efficiency of automated storage equipment. In fact, all the dynamics of a warehouse can benefit from a slotting analysis since it improves average warehouse throughput, productivity by piece of equipment, productivity by picker, order turn-around time, and overall throughput to meet peak demands.

What is the difference between manual warehouse operations with an ERP and using an ERP with a WMS?

With a software-based WMS, operators use hand-held devices to do the inventory management and accounting. As soon as the operator hits “enter” on the device, that transaction is created and on the next iteration of communication with the ERP, the data is sent. This combination of WMS and ERP offers real-time inventory management, informing warehouse managers about exactly what happened and when. It’s much more efficient, faster, and more accurate than paper-based systems.