Warehouse and DC Order Fulfillment: Locke Supply’s path to accurate productivity

The resurgent housing market has been a boon to Locke Supply, a plumbing, electrical, heating, and cooling products distributor based in Oklahoma City, Okla. But along with growing demand came escalating challenges in accurately fulfilling orders to its 160-plus branch stores from its central distribution center (DC) in Oklahoma City.

The stores serve plumbers, electricians, and other contractors as well as consumers across five states. The order mix from the stores is varied, from small plumbing parts or electrical components to big-ticket items like water heaters. Unlike a product manufacturer shipping full pallets or cases to a Big Box store, a core challenge at Locke is accurate picking of items in a pick-to-pack process so that the stores have what they need.

By late 2012, growing demand along with the picking challenges were leading to steadily increasing problems at the DC, according Larry Zeller, Locke Supply’s CIO.

“Our primary concerns were to improve picking accuracy, reduce the amount of time it takes to train our people, and along with that, reduce employee turnover,” says Zeller. “There wasn’t one particular moment that triggered the decision to change our systems, but our sense was that the problems with order accuracy, training, and turnover were accelerating.”

The solution Locke Supply turned to was a voice picking solution from Vocollect that integrates with its warehouse management system (WMS) to provide voice-directed picking. The solution, says Zeller, has fulfilled Locke’s productivity goals within the DC, and as a result, is getting positive feedback from managers at the branches.

“Long before the voice system was put in, we encouraged feedback from our branches, and we would frequently hear about problems,” says Zeller. “Now after putting in the system, it’s just the opposite. We’ve received a lot of calls and e-mails from the branches telling us how great the accuracy has been.”

Picking challenges
Locke Supply has grown from a one-store operation founded in 1955 to a large regional distributor with 166 branches serving five states. The DC’s picking takes place during the night shift, with 10,000 to 12,000 order lines per day. Those orders are picked from an inventory of about 27,000 stock keeping units (SKUs) that are normally on hand at the approximately 300,000 square-foot DC.

In 2005, the company implemented the Total Warehouse Logistics (TWL) WMS from Infor to control inventory and operations at the DC. Prior to the voice solution, pickers used radio frequency (RF) terminals to access pick lists, instructions, and record picking activity.

Picking of smaller items is done on a mezzanine level where pickers place the items into cardboard boxes and put them on a motorized conveyer, which then moves the goods down to a pallet building where the store shipments are staged. Workers using lift trucks and motorized picking carts pick larger items from other areas of the DC.

Accurately and efficiently executing all of this picking activity was challenging with handheld RF terminals, explains Shane Bruner, application support analyst for Locke Supply who led the implementation of the voice solution. According to Bruner, workers would have to learn how to scroll through and navigate the terminal user interface as well as how to input the correct information to confirm picks.

“With an RF system, you have a handheld unit that is driven by function keys and what can seem at times cryptic screen messages,” says Bruner “It simply takes longer to train pickers on that type of system, especially if they have no experience with RF terminals. Not only that, in comparison to voice picking, you always have to keep an eye on the device, so immediately, the picker’s attention is cut in half.”

Multiple problems arose from these challenges. Order accuracy was estimated to be in the 95 percent accuracy range. Turnover was high—so high that at one point, much of the picking had to be done by temporary workers. This left the DC leadership constantly struggling to train temporary workers on how to correctly use the handheld terminals to execute their picks.

Finding the solution
During the time when the problems at the DC were growing, Zeller, Bruner, and another manager for Locke Supply were at an independent conference for users of Infor’s distribution software when they came across a voice picking solution from Honeywell’s Vocollect that integrates with WMS data and uses wearable, RF-enabled hardware.

Picking information and instructions are conveyed to the worker via voice command to guide picking activities. Instead of carrying a handheld terminal, pickers have a small terminal clipped onto a belt and wear a headset that keeps both hands free.

When Locke Supply’s managers saw the voice solution at the conference, and noted that it had the potential to significantly cut training time and reduce errors, the decision was quickly reached to deploy the system.

While integration between the Vocollect system and TWL was a first and took some extra time to set up and test, implementation of the voice picking itself was completed in under four months, going live in March of 2013.

The solution was rolled out by picking zone, says Bruner, rather than across the whole DC at once. Training for a picker was completed in about three hours—versus the three days it previously took to fully train a picker using a handheld RF terminal. Bruner and Zeller attribute the dramatic improvement in training time to the intuitive nature of voice commands.

“It’s more complicated when you put a device in someone’s hands that they have to operate themselves by punching in commands and navigating a screen,” says Bruner. “There tends to be this immediate sense that they might mess something up in the way they are using the device, so they don’t trust their abilities with the device. By contrast, with the voice system, you put on the device, you are assigned a zone, and you are off to the races. Everything is voice directed, so it takes much of the complication out of it.”

Zeller likens the leap in training simplicity to getting voice directions from smart phone map app versus trying to find a location by reading paper maps and street signs. “Your eyes are free, and your hands are free, and you are just following instructions,” says Zeller.

Productivity improvements
The training ease of voice-directed picking carries over to operational productivity improvements. Rather than having to navigate on a screen to see pick instruction or find where to record data, everything is a simple audio instruction or prompt, says Bruner.

For example, rather than having to key in the number of items picked for an order, the voice system says, “pick four” from this location, and the worker confirms the pick is fulfilled by responding “picked four” into the headset. The system also uses simple voice commands to confirm that the picker is in the correct zone and guides the picker to the correct aisle and shelf location.

So, instead of scrolling down a screen or using the keypad, the picker simply listens for instructions and verifies by speaking simple responses like “ready.” If the user ever wants to double check if the right item is being picked, the picker just calls out “item number” to hear the correct information.

The productivity improvements have been significant for Locke Supply, which uses the solution for all of its picking, though not for put away and replenishment. While picking large items like water heaters takes longer and occurs across all zones, the average pick rate is now around 200 picks per hour, up from around 110 picks under the previous process. At the same time, order accuracy, once down near 95 percent, now exceeds 99 percent accuracy.

“Overall, we saw our picking rate close to double,” says Bruner. “I was also amazed at how quiet it was in the warehouse after we first deployed the system because there was no cross talking. Everyone was focused on interacting with the voice system, getting a good pace going, and wanting to move fast.”

In Zeller’s view, voice-directed picking helps productivity because it takes away the complication and distraction of having to manipulate a device. “With voice, the pickers are focused on the task at hand,” he adds.

Deeper improvements
Other improvements attributed to the voice systems, says Bruner, include better battery life for the device hardware. With the old handhelds, at least one battery swap was needed per shift, whereas the voice hardware easily lasts an entire shift on the same charge. The wearable hardware also can’t be dropped like a handheld, so repair and replacement issues effectively have been eliminated.

The greater order accuracy in the pick to pack process also has helped the warehouse managers identify problems in replenishment that were not apparent when the picking process was more error prone, says Bruner.

The ease of training and ease of use with the voice system also has helped to “substantially” improve worker retention, says Zeller. Whereas once it was common to have 60 percent of pickers in a zone being temporary help because of the turnover rate, today, the vast majority of picking is handled by full-time staffers.

Best of all, says Zeller, has been the positive feedback from the branches on improved accuracy. The bottom line is that the company is able to more accurately move more orders than ever.

“We’re finding we’re able to fulfill this increased volume in less time and with fewer people,” says Zeller. “Given the volume we are now handling, we would probably be in serious trouble with our DC operations had we not implemented this system.”