American wholesaler SuperValu has seen a boost in operational efficiency and is now able to handle more volume in a smaller footprint at its Lancaster distribution centre in Pennsylvania after installing Witron’s automated case picking system, Order Picking Machinery.
“After nearly two years of successful operation at Lancaster, OPM has proven it can effectively handle our daily operations while remaining flexible enough to respond to our seasonal requirements…We see this technology as a blueprint for other case picking DCs in our network,” said Fred Boehler, senior vice president, supply chain at SuperValu.
The company chose Witron after it installed a similar system at its Hopkins facility in Minnesota.
The OPM system begins at receiving, where vendor pallets are manually uploaded from inbound trailers and conveyed to a pallet AS/RS for storage, which can hold more than 54,000 pallets in double-deep locations. At the Lancaster site, SuperValu feeds a ten aisle pallet AS/RS from six receiving lanes.
Poor quality vendor pallets are automatically detected and exchanged in receiving.
The pallet AS/RS serves as reserve storage and the product required for picking is held in a tray AS/RS.
The Witron WMS triggers replenishment from the pallet AS/RS to the tray AS/RS based on replenishment algorithms, which consider SKU velocity based on sales history, forecast data and upcoming promotions to make sure the right product is available.
The replenishment strategy helps to ensure the highest store service level in terms of pick accuracy, product availability and just-in-time delivery for customers.
The process of transferring cases from pallet to tray during replenishment is also automated. The Lancaster warehouse has eight depalletising machines that use suction heads and inflatable bellows to strip layers of cases from replenishment pallets.
The conveyor system converts this layer into a single stream so that individual cases can be automatically placed on top of one of two sizes of plastic trays.
The proper tray size for each SKU is based on actual case dimensions to ensure maximum storage efficiency. Witron adjusted the system parameters so that 95 per cent of SuperValu’s 18,000 SKUs could be handled automatically through the entire system.
After depalletising, single case trays are stored in the tray AS/RS that feeds the automatic pallet building process. The tray AS/RS consists of 44 cranes, with more than 400,000 trays.
Pallet building
The tray warehouse is designed so that all SKUs are accessible for pallet building. The miniload cranes in the tray warehouse are able to handle two large trays or four small trays at one time.
Trays are retrieved from storage based on actual order demands and conveyed to the COM (Case Order Machine) where pallet building takes place.
Witron’s pack pattern software determines the proper sequence of trays for automatic pallet building based on various parameters like case size, weight, crushability and family group rules. The pack pattern software sequences the cases for the optimal pallet build, while the COM provides the mechanical means to remove the cases from their trays and stack them onto the pallet. The COM uses a pushing mechanism rather than a traditional robotic gripper, to help minimise problems associated with poor packaging and eliminates any gaps between cases on the order pallet.
The Lancaster facility features 22 COMs, allowing SuperValu to pick 256,000 cases per day. The completed order pallet is automatically stretch wrapped and labelled after pallet build to maintain its integrity in shipping and during transport.
The system was installed on time and within budget without any interruption to store service. Within the first two months of going live the Lancaster DC was able to pick and ship more than 100,000 cases per day.
To date, the Lancaster site has picked more than 100 million cases and delivered more than 1.3 million order pallets, servicing nearly 400 stores each day.
The OPM system was able to fit in the existing Lancaster facility, while the AS/RS pallet load system was a building addition of 175,000 sq ft by 70 feet high. The retrofit of the existing facility with OPM technology allows SuperValu to handle more volume in a smaller footprint.
Witron claims the OPM system can reduce conventional warehouse footprints by 40 per cent, and greater footprint savings are possible in greenfield projects where building height can be maximised.
Although labour is still required on the receiving and shipping docks, indirect labour for tasks such as inventory control and auditing can be eliminated or significantly reduced.
Another benefit is the reduction in conventional material handling equipment, including reach trucks, forklifts, picking cars and battery charging equipment.
“Apart from these financial savings, the OPM means less physically demanding work for associates, offering a more technically advanced work environment,” says Jeff Fritz, Lancaster senior director of operations at SuperValu.
“This translates into lower health and safety costs, improved employee retention, and the ability to attract a new generation of warehouse workers.”
OPM is also designed to eliminate picking errors, reduce damage and improve store shelf replenishment efficiency, thereby reducing labour hours required in the stores.
