In most distribution centers, order selecting is the most manual, labor-intensive, and high priced operation. It can account for up to 60% of the operation costs. Companies tend to focus on this area first because a variety of enhancement can positively have an impact on their customer’s experience. The distribution center decides on the people picking gadgets from cartons on warehouse cabinets and putting them into boxes for cargo to customers. Picking requires coordination, organization, and thoroughness so that distribution centers easily fill the widest range of orders in the shortest time. The diagram below shows the estimated cost of each function as a percentage of the annual operating cost of running a distribution center.
Ecosystem of Order Picking
Warehouse managers regularly search for strategies to restructure the choosing technique due to the fact it can be time-consuming and costly if no longer executed as effectively to maximize productivity. However, they additionally feel compelled to enhance choosing practices to meet and exceed consumer expectations, as each choosing velocity and accuracy have an effect on customer’s satisfactory.
The diagram below shows the basic ecosystem of order picking.
Methods of Order Picking
1. Discrete Order Picking
The most common type of order picking is basic and simple to understand. When employing a discrete order picking methodology, one order-picker picks one order, one line at a time. The main advantage of using this method of order picking simplicity. This is ideal for paper-based picking provides a fast response time for order fulfillment and can easily track order picker accuracy. However, this is the least efficient method as it requires more travel time compared to other methods.
2. Zone Picking
Order pickers are assigned a specific and physically defined zone in the pick area. The picker assigned to each zone is responsible for picking all of the SKUs located in the zone for each order. In the event that order requires SKUs that are located in multiple zones, the order is filled after it passes through each zone. This is also referred to as the “pick and pass” methodology. In zone picking, there is only one scheduling period per shift. This means there is a cut-off point for orders to be queued into the order picking process and any order received after that cut-off point will get fulfilled during the next shift.
3. Batch Picking
Batch picking is when one picker picks a group, or batch, of orders at the same time, one SKU at a time. This is advantageous when there are multiple orders with the same SKU. When that occurs, the order picker only needs to travel to the pick location for that specific SKU once, in order to fill the multiple orders. The main advantage of choosing this method is the reduced travel time, which increases productivity. Batch picking is often used when the typical order profile has only a few SKUs (under four) and the SKUs physical dimensions are relatively small. Just as in zone picking, batch picking requires only one order scheduling window per picking shift.
4. Wave Picking
Wave picking is very similar to discrete picking in that one picker picks one order, one SKU at a time. The main difference is the scheduling window. In discrete picking, there is not a scheduling window whereas in wave picking there is. Orders may be scheduled to be picked at specific times of the day, which is usually done to coordinate and maximize the picking and shipping operations.
5. Zone-Batch Picking
This is a combination of methods in that pickers are assigned a zone, just like traditional zone picking, however they are also directed to batch pick within their zone. Since both zone picking and batch picking have a scheduling window, then zone-batch picking does too.
6. Zone-Wave Picking
Zone-Wave Picking is a combination of methods in that pickers are assigned a zone and each picker within their zone picks all of the SKUs for all orders that are stocked in their zone, one order at a time with one scheduling window per shift.
7. Zone-Batch-Wave Picking
The most complex combination of all of the order picking methodologies. Each picker is assigned a zone and picks all SKUs for orders stocked in the assigned zone. Additionally, the picker picks more than one SKU at a time and there are multiple scheduling windows per shift.
The Order Picking Techniques
Improving efficiencies within the order picking process keep customers happy, and order picking accuracy improves the bottom line. Below are some techniques to improve order picking at distribution centers.
1. Touch items once
Focus on preventing errors during picking and you won’t need further repacking, or shipping checking. Picked inventory should go on trucks touched only by pickers. Also, pick into shipping cartons instead of a tote.
2. Rely on system verifications
Design your standard operating procedures to double-verify almost every step in the picking process. You can loosen this later as needed. For example, utilize area’s pick verification flags to have user scan and verify LPN, quantity, item, etc. Count Back or Count Near Zero can also be used to count remaining inventory in a location in-line with picking.
3. Consider different storage strategies
Different storage strategies can boost efficiency within a warehouse. For example, slotting may improve storage intensity, reduce accidents or product damage, reduce congestion and improve retrieval times. Review storage strategies on a regular basis in order to align your practices with seasonal demand.
4. Create a warehouse within a warehouse
You can gain tremendous efficiency by grouping together the 20 percent of your SKUs that complete 80 percent of your orders. This cuts down on travel time for your pickers. Be sure, however, that the 80/20 area or zone is properly designed to accommodate high-volume activity.
5. Consider different order picking methods
• Zone picking: Each order picker is assigned a specific zone and will only realize order picking within this zone.
• Batch picking: An order picker is assigned and picks multiple orders simultaneously, minimizing trips to each location.
• Wave picking: A variation of zone and batch picking. Rather than orders moving from one zone to the next for picking, all zones are picked at the same time and the items are later sorted and consolidated into individual orders/shipments
• Consider automation: Order pickers spend about 60 percent of their time walking product or moving product around. Consider an automated solution, such as conveyance, to reduce their extensive travel time. Add workstations with the power to eliminate wasted steps.
• Eliminate walking and reduce fatigue for more accurate picks: You make more mistakes when you’re tired, and so do your order picking employees. Try to keep them still, not moving and you’ll see faster picks with fewer errors.
6. Look for family groups
If you would like to make completing multi-line order picking via a short picking path the norm and not the exception, then analyze how customers place orders to slot your pick faces and group your items. This can take time to complete but can be very rewarding, as it ultimately reduces travel distance, your picking enemy #1.
7. Consider using Pick Stealing
Newly received Inventory may sometimes represent an alternate source for picks that have yet to begin. Picks sourcing from interior storage could then be redirected to source from receiving area instead. If the receiving area is adjacent to the picks’ destination, this redirection will reduce product movement and therefore improve operational efficiency. Keep in mind that cross-docking takes precedence over pick stealing, given that the former is pre-planned and the latter is an ad-hoc process.
Receiving, transfer and put away, order picking, cross-docking, and transport is the principal warehouse activities. Among these activities, order picking is the most labor-intensive and steeply-priced recreation for the most distribution center, which about 55% of the whole distribution center working charges are associated to order picking operations. This explains that improving order-picking efficiency is crucial.
The picture below shows an automated batch order picking system.
An efficient and well-run order picking process is one of the most essential features in a distribution center, and this needs to be reviewed and revised periodically for the most beneficial overall performance and meeting customer’s satisfaction. By accomplishing high throughput rates, it is crucial to enforce safety procedures and shop time where is it possible. Thus, well-planned order picking is key in this aspect. Hence, efficient and streamlined order picking is one of the most important functions in a warehouse and needs to be reviewed and revised periodically for optimum performance.
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