The distribution center houses over 1 million book titles in quantities ranging from multiple trailer loads of popular titles to one or two volumes of very obscure books. Accordingly, inventory storage media varies from high-rise, narrow aisle pallet rack to flow rack and finally to acres of multi-level shelving.

Virtually all aspects of the distribution process are automated. Tracking labels are generated and automatically applied to cartons at receiving. Multiple sortation systems deliver inventory to storage and picking locations. Batch picking is directed by RF interface and routed through zones by scanner directed diverters. Book orders are simultaneously assembled from each picking batch by tilt tray sorters.

Over 13 miles of Hytrol conveyor carries cartons and totes through all of the distribution processes, from receiving to shipping. The entire system is monitored from a central control room equipped with displays that indicate the status of all areas of operation.

Receiving

For receipts of less than pallet load quantities, inbound cartons are conveyed to a mezzanine above the receiving dock where they are scanned and matched to a database of purchases. A 380-foot long Hytrol Prosort shoe sorter directs cartons to a series of receipt processing and audit stations. After processing, cartons are reintroduced into the receiving sorter for routing to pick locations, cross-dock, or active order fulfillment. Sortation is performed at rates up to 140 cartons per minute.

Inventory Replenishment

Forward pick locations and shelving mezzanines are supplied by a series of conveyors and sorters that deliver replenishment inventory. Cartons arriving from either bulk storage or the receiving subsystem are sorted to the three levels, and then by specific zone within each module for put-away to dynamic primary pick locations.

Picking

Each of the eight picking modules in the system is three levels high. Order selectors are given location and quantity instructions through scanner equipped radio frequency devices. Within each level, a series of scanners and diverters automatically direct cartons to only those zones where picks are required. Orders that can be completed within a single 3-tier pick module are conveyed directly to carton sealing and labeling stations. Batch picked cartons and totes containing books needed to fill multiple orders are conveyed to the packing sorter.

Order Consolidation

The packing sortation system is a tilt tray design. Individual books are placed on belts at induction stations and are sorted to chutes that each represents a single order. Indicator lights at the discharge of the chutes direct packers to remove the chute contents for packing as orders are completed. Chutes are reassigned to new orders as subsequent batches or waves arrive at the tilt tray induct stations.

Packing

Open cartons, containing completed orders, are conveyed to a series of taping and print & apply stations. Cartons are sealed, weighed, and labeled before they are automatically inducted into the shipping system. Single book orders, selected by batch into totes, are sorted to specially equipped packaging stations for quality inspection, packaging, and labeling before being sent to manifesting and shipping lines.

Shipping

The shipping sorter is a single loop tilt tray design, capable of sorting up to 170 cartons per. minute to shipping doors and small package Gaylord positions. Shipping door positions are equipped with flexible, extendible conveyors for truck loading.