When retailers first began dabbling in e-commerce—whether as a pure play or as a supplement to their brick-and-mortar operations—they often were able to get away with handling order fulfillment manually. But now, as online retailing explodes, they're finding that approach just doesn't cut it. In order to keep up with the increase in volume and the demand for faster turnaround times, they have to automate. At the very least, they have to put in conveyors and sortation systems.
But as they do so, many companies are discovering that the systems that work well for supplying brick-and-mortar stores aren't a good fit with direct-to-consumer operations. That's because the characteristics of e-commerce orders are very different from their store-based counterparts.
These differences have a number of implications for fulfillment operations. First, when you're shipping directly to consumers instead of stores, the volume of orders is going to be higher. Second, instead of transporting cases or broken cases, conveyors and sortation systems have to be able to handle individual items. On top of that, there's packaging. In a bid to cut costs, more companies are choosing to mail out e-commerce orders in polybags or envelopes rather than corrugated boxes, according to Stephen Cwiak, vice president and general sales manager at conveyor manufacturer Interroll.
THE RIGHT FIT
All of these characteristics have a big impact on what type of conveyors you use or how you use them. For instance, small items, soft goods, and items packaged in bags or envelopes typically aren't a good fit with conventional roller conveyors.
"Because you can't rely on the item's having a large, firm, flat-bottomed surface, there's a potential that the item will end up going up and down between every roller," explains Tim Kraus, product manager for line sortation at systems integrator Intelligrated. As a result, he says, small things could get stuck between rollers, and you don't have as much control of the movement of the bagged items as you might like.
In comparison to roller units, belted conveyors provide a better ride for small and bagged items, making them a good match for e-commerce. However, they typically cost more than the more popular roller conveyors. And not every company is willing to shell out for the more expensive systems, especially if they already have a roller conveyor that they're hoping to repurpose for e-commerce operations.
One way to get around this is to batch-pick items into a tote, according to Kelly Reed, a partner with the consulting firm Tompkins International. The totes can then be transported by traditional roller conveyors to a unit sortation system or put-to-order module, where the items are allocated to individual orders and packaged.
After the orders are packed, orders in cartons can be separated from those packed in polybags or envelopes, Reed says. The polybag or envelope orders can be deposited back into a tote and routed to a shipping sorter, where they can be manually sorted for shipment.
Not only are totes an economical option for companies looking to make use of existing equipment, but they're also a good fit for those retailers that sell a mix of products. One such company is online women's fashion retailer JustFab. Most of the company's volume consists of shoes, which can be easily transported on roller conveyors in shoeboxes. But the company also sells soft goods, such as jeans, purses, and accessories. For these items, the company uses totes. (See sidebar for more on JustFab's fulfillment operations.)
The majority of JustFab's orders are packed in corrugated cartons. The remainder are polybagged and handled manually, using a process similar to the one described by Reed. "Polybags are such a small percentage of our business that we chose not to [automate] it," says Bert Hooper, JustFab's vice president of operations. "We tote up our sealed polybags and send them to a manual shipping station, where our employees apply shipping labels and sort them into gaylords [large reusable corrugated containers used for shipping]."
If a facility has no choice but to use roller conveyor for transporting small bagged items, Kraus recommends that the rollers have tighter roller centers than the standard three to four inches. He also suggests setting any sensors used with the conveyor to detect small items.
On top of that, the company should pay particular attention to catch points—places on the conveyor's frame where the bags might get snagged. These include corners, guardrail "transition" areas, and areas where one piece of sheet metal overlaps another. Rigid cartons are less likely to get snagged or drag on these points than a bag, which conforms to the shape of whatever you set it on, says Kraus.
SORT IT ALL OUT
As is the case with conveyors, the best sortation systems for brick-and-mortar fulfillment may not be the best ones for e-commerce fulfillment.
Mitch Johnson, director of systems development for Hytrol Conveyor Co., notes that typically, sorters in DCs that supply retail stores are set up to handle 200 orders. This works well in a store fulfillment environment, where those 200 orders may contain thousands of items. But in an e-commerce operation, the average order only contains 1.5 items. If your systems can only process 300 items, you aren't going to be able to keep up with the volume and velocity requirements of e-commerce, Johnson warns. "So you have to look at different ways to do it."
To handle that kind of volume, Johnson suggests using sortation systems that offer a lot of sort points in a small area, like a tilt-tray sorter or a cross-belt sorter.
In addition to volume, the type of packaging used will affect the choice of sorter. If you're just handling cartons, Reed recommends using a sliding-shoe sorter. This type of sorter is well suited to the small, mostly lightweight cartons that are common in e-commerce operations, he says. Sliding-shoe sorters also work well when you're routing a high volume of goods or totes to different order processing or consolidation areas, says Clint Lasher, divisional president, engineering and integration, Oak Lawn (Ill.) for systems integrator Wynright. For lower volumes, a pop-up sortation system would work well, he says. JustFab, for example, is using a pop-up wheel divert sorter.
If you're sorting bagged items, however, things change—including the criteria you use to decide what type of sorter to deploy. According to Kraus, with cartons, you only have to know the size of the cartons, the range of carton sizes, and the rigidity of the cartons. With bags, you not only need to know the size of the bag, but also the size and rigidity of the item(s) inside the bag and how closely the size of the item or items matches the size of the bag. "If it's a large bag with very small items, that becomes more difficult to handle because there are more catch points and a bigger opportunity for snags," he says.
The rigidity of the bag itself also plays a role, says Kraus. Most direct-to-consumer orders use a very thin polybag with no structure or rigidity. In those cases, Kraus says, a loop-type sorter, such as a tilt tray, cross belt, or bomb bay, is a good choice, assuming the operation or layout will accommodate it. Another good choice is a positive line-type sorter, such as a sliding shoe, pusher, or sweep divert. However, friction-based line sorters, such as pop-up wheels, pop-up rollers, or angled roller belting, do not work as well because of the bag's lack of structure or rigidity, Kraus says.
Interroll's Cwiak specifically recommends cross-belt sorters for handling polybagged items. A cross-belt sorter does a good job of sorting soft goods without their becoming tangled or being mishandled, which is known to happen with narrow-belt sorters, sliding-shoe sorters, and tilt-tray sorters, he says.
TIME FOR A PARADIGM SHIFT?
Although analyzing equipment needs is an important part of the process, there's more to preparing an operation for e-commerce than modifying or replacing the conveyors and sortation systems, cautions Steve Schwietert, vice president of integrated systems sales for systems integrator TGW. Schwietert strongly urges DCs to re-examine their entire paradigm for picking, packing, and shipping items. For example, he argues that goods-to-person systems, such as automated storage and retrieval systems and miniloads, are much better suited to e-commerce than traditional picking methods.
Conveyors, of course, will still be needed to transport goods to and from those systems. Indeed, Lasher says that e-commerce fulfillment will require a lot more routing conveyors to ensure goods are moved around the warehouse in an intelligent fashion.
Motor-driven roller conveyors work well for transporting goods into and out of goods-to-person systems because they're easy to deploy and control, Schwietert says. And because they're modular, they give users the flexibility to change configurations as needs shift, says Lasher.
The paradigm shift may extend beyond simply redesigning your distribution center. For example, Johnson of Hytrol says he can envision a day when retailers—in an effort to respond to demands for same-day delivery—install automated equipment like conveyors and sortation systems in the stores themselves. In this scenario, store employees would pick orders from the site's inventory for customers to pick up the same day.
Whether or not these dreams become reality, this much is clear. E-commerce fulfillment presents both challenges and opportunities. And it has likely changed the fulfillment game for good.
When it comes to the front-end selling experience, the online women's retailer JustFab has always been tech savvy, with a Web operation that pushes monthly recommendations for shoes and handbags tailored to a customer's personal style. On the back end, however, the pure-play e-commerce retailer was—until recently—anything but high tech.
Bert Hooper, the retailer's vice president of operations, recalls that when he joined the company in June 2011, its Louisville, Ky., warehouse was an entirely manual operation. While that worked well enough when the company was starting out, it was becoming increasingly clear JustFab would have to automate in order to stay competitive. "You get to the point where it's costing you too much money to manually process the order," says Hooper.
JustFab needed to reduce its variable labor cost per unit and its cycle times in order to stay in the game. In addition, it had to come up with a more efficient way to handle multiple unit orders (when a customer orders more than one item at a time) than simply sending associates out to collect items on carts. After weighing its options, it installed 1,500 feet of conveyor and sortation systems from Intelligrated, along with various other systems.
Today, JustFab's DC associates pick directly onto the conveyor system. The orders then travel to the sortation system, which diverts multi-unit orders back to the "binning" area to collect the remaining items, and sends single-unit orders and completed orders on to the packing area.
The sortation system has six divert lanes for multi-unit orders, with 200 bins per divert lane. This means the company can have up to 1,200 multi-unit orders in the system at one time, flowing between picking, packing, and shipping. This is in addition to the 1,000 single-unit orders that the system is concurrently handling.
As a result of the shift to the new system, JustFab has been able to keep up with the rapid increase in volume. Since 2011, the company has grown from an operation with 200,000 units in inventory that processed 2,000 orders per day to one that handles 1 million units of inventory and 8,000 orders a day.