Order picking is a process that supports the core functionality of a warehouse, so it’s one that warehouses must get right. Not only is it a core function within a warehouse, it accounts for roughly 55% of the cost of warehouse operating expenses. Warehouses may rely on one or more order picking methodologies (such as zone picking, batch picking, or wave picking), while some have turned to automation to make their order picking staff more productive.
No matter what methodology is used, warehouses share a common goal: improving both the efficiency and accuracy of the order picking process. To achieve these goals, warehouses follow several best practices:
- Analyze product velocity
- Organize inventory strategically
- Establish picking routes
- Maintain accurate inventory data
- Analyze error data
- Automate as much as possible
1. Analyze product velocity
The organization of a warehouse’s inventory can make or break efficiency when it comes to order picking. Within the industry, this can also be referred to as “proper slotting of the product.” “Slotting” is a term used for locating the inventory within a pick area. It can also be “velocity based slotting”, which takes product velocity into account.
If pickers are required to walk the full span of the building several times to pick commonly needed inventory, your warehouse layout is not optimized.
Analyze your travel time, product velocity and other data, and locate fast-moving inventory in the most easily-accessible racks – ideally, racks that are nearest to the shipping or loading dock destinations.
2. Organize inventory strategically
Slotting, which refers to the careful placement of individual cases within the warehouse, can also help to optimize your warehouse layout. Grouping similar items together makes inventory easier to locate, which in turn reduces picking time. This is also known as zoning, or creating established areas for distinct inventory types and categories, which is typically paired with zone-based order picking. In zone picking, order pickers are assigned to specific zones and pick only orders from their assigned zones. Hot zones, or zones that contain the SKUs that generate the most picking activity, lead to a higher pick density, which is a proven way to improve productivity.
Batch picking can also be used with a zone-based layout. In batch picking, associates pick multiple orders from a specified zone in a single trip. Wave picking, on the other hand, is a combination of zone and batch picking in which pickers pick multiple orders from multiple zones at the same time. After picking, the orders are then divided into separate orders. With any of these picking methodologies, having strategically organized inventory speeds up the process.
Finally, slotting similar products in a checkerboard style to prevent confusing similar products in adjacent bins helps with order picking accuracy.
3. Establish picking routes
Once you’ve organized your warehouse layout according to product velocity or by grouping similar items together, it’s easier to establish preferred (or required) picking routes. By establishing the best routes for picking various types of inventory, you remove the guesswork surrounding getting to the right inventory, so workers – human or machine – can focus on accuracy.
Picking routes are also dependent on picking methodologies, but generally can be established to ensure that order picking is conducted in the most efficient way possible, eliminating common issues such as backtracking through aisles that have already been passed through, which adds to total picking time and overhead costs.
4. Maintain accurate inventory data
While the strategies above can improve picking accuracy, they’re only as effective as the foundation they’re built upon: accurate inventory data. Inventory should be easily located with signage, rack labels and other warehouse labels, and products should be readily identifiable.
After all, having all your inventory in the optimal locations and having established picking routes for efficiency means little if the inventory needed is out of stock or not where it’s supposed to be. Maintaining accurate inventory data provides better visibility into your warehouse operation and can also provide insight into product velocity and other metrics.
5. Analyze error data
Your operational data holds many secrets that, when identified, can dramatically improve your ROI. Collecting and analyzing data on picking errors can help you identify the specific point at which errors are typically occurring, for instance, allowing you to laser-focus corrective actions on the points of error.
Posting individual or group error rates is a strategy that some warehouses use to increase awareness among team members. That said, positive reinforcement may be more effective, so you may opt to incentivize accuracy through bonuses or other perks.
6. Use smart automation as much as possible
When humans are directly involved in any process, errors are likely to occur, and in the case of order picking, it’s a process which, by nature, is rather inefficient. Warehouse order pickers can spend more than half of their time traveling from point to point within a warehouse to pick orders, creating a lot of wasteful overhead.
Fortunately, there are many technologies that automate long-standing warehouse processes, from barcode scanners to conveyor belts to shuttles and mobile robots, all with the goal of reducing the time workers spend moving products manually. Some of the best automation solutions for warehouses augment the work of humans rather than replacing them, allowing warehouses to increase picking accuracy and boost efficiency without losing that human touch.
Order picking accuracy can make or break the success of a warehouse operation. Following these steps and implementing these strategies will help to streamline processes and enhance both accuracy and efficiency, so your warehouse can do what it does best, but even better.