SDI Greenstone

Systems integrator SDI Greenstone has installed a high speed custom-designed automated sortation and conveyor system for Belgium's leading book distributor La Caravelle. The system is currently handling around 18,000 individual books each day, and now enables La Caravelle to despatch orders on the same day as they are received.

La Caravelle, based in Brussels, distributes books to around 1,500 outlets in the Benelux countries and every day processes up to 600 orders. The SDI Greenstone system takes books picked from the bulk store into an automatic sorter where they are separated into orders for individual stores. Cartons of sorted books then pass through automatic labelling and sealing machines onto a robotic palletiser, ready for onward delivery.

As orders are received at the Brussels distribution centre (DC), the required titles are picked from the bulk store – which consists of shelving, a mezzanine floor and very narrow aisle racking - and placed into cartons that travel along powered conveyors to the sorter's three induction stations. The books are taken from their cartons and their publishers' bar codes are read by in-line scanners as they pass onto the sorter carousel, carried on trays. Beneath the carousel are 111 drop stations that La Caravelle assigns to individual stores. A carton is placed at each drop station.

The system's software protocol, linking to the DC's order processing platform and triggered as the items are scanned at the induct points, automatically counts the progress of each tray-set round the carousel. As the tray passes over the appropriate drop zone the software activates solenoids to tilt the trays, releasing the books into the cartons.

SDI Greenstone's sister company SDI Promech, based in Holland, specially adapted the tilting tray system to provide a particularly 'soft' action, even when the sorter is operating at full speed, so the books slide gently from their trays down an angled chute onto an inclined roller bed and then into the store cartons. This slows the books down as they are released from the sorter's trays, and eliminates any risk of damage – a major condition that La Caravelle imposed upon SDI Greenstone when the system was being designed.

Lights above each drop station indicate when individual store orders have been completed, and a line-side PC carries full 'at-a-glance' information on the status of the whole sortation process.

As store orders are completed, indicated by the light above the drop station, a bar-coded packing list, with invoice, is manually placed on top of the books (the list tells the staff which drop station to go to). The cartons then leave on a powered conveyor, running round beneath the sorter carousel, and are carried on an overhead gantry (which frees-up valuable floor space) to an in-line scanning station. The scanner reads the bar-coded packing list and automatically generates an address label, which is applied by an in-line printer further along the conveyor. The cartons then pass to an automatic closing machine and onto a shrinkwrapper and robotic palletiser. All goods leave the Brussels DC on pallets, to be broken down at distribution satellites for final delivery.

The SDI Greenstone system has the facility to take assembled orders (particularly for large quantities of single titles – best sellers, for example) direct from the bulk store to the scanner and labeller, by-passing the sorter.

The installation also includes an automatic carton erector that feeds empty boxes to the drop stations and a spur conveyor that returns into the system the cartons in which the books arrive at the sorter from the bulk store.

La Caravelle is receiving up to 600 orders a day (400 repeat orders and 200 for new titles). Orders are taken up to 12.30hrs, at which time the bulk picking commences. At 15.00hrs the picked books are sent to the sorter, and by 17.30hrs the orders are despatched.