The site in Tongeren was built in ’94 for the purpose of distributing spare parts. The WMS was implemented a year later. The EDC, with 45,000m² of warehouse space, is used both to supply goods to the distributors of SKF as well as for logistic operations for external clients. WASS supports goods reception, resupplying, picking, packing, loading and stock control. Value added services, such as kitting and assembly, are managed without paper as well. In other words, the flow of information has been fully automated throughout the entire warehouse process. All instructions are sent to the instruments of the logistics staff via the Radio Frequency (RF) network. A single interface creates a link to the ERP that SKF has developed itself as well as to the ERP systems of external clients. We will mainly limit ourselves to the operations for SKF itself when we illustrate the functioning of WASS further on in this document.
Inbound flow
An average of 30 trucks is unloaded in Tongeren everyday. The majority of the goods that reach the EDC stem from SKF factories. SKF Logistics Services can dispose of more than 100,000 SKUs (Stock Keeping Units) for the activities of SKF. Many products arrive in crates, which are also used as dispatch units further along in the process. The EDC is informed via an ASN (Advanced Shipping Notice) about 24 hours beforehand about which goods are to arrive. Moreover, it has been agreed with the factories that the products are to be supplied in the same configuration, time and again. For example, product x is always supplied per 180 pieces on a pallet of certain predefined dimensions. "Combined, it usually allows us to scan the pallets upon arrival as received without any additional inspection and to place them on the inbound conveyor," says Joris Leys. "At the same time, we automatically check the size and the weight. We have a reject lane for pallets of the wrong size or damaged pallets. The goods that arrive will be available to the client within two hours after the lorry has docked."
Storage and Control
An important aspect within the warehouse operations at SKF Logistics Services concerns the ASRS (Automated Storage & Retrieval System). This automated high bay warehouse is 25m high, 100m deep and it has seven cranes and 60,000 locations. The cranes are controlled via PLCs, which are linked to WASS via the Sattmate interface. The goods are stored double deep for an optimal efficiency of the system (for two specific SKF pallets or a single euro pal¬let) and the goods are stored either closer to or further from the outgoing zone depending upon the picking frequency. We can store 200 pallets per hour.
The bulk stock is stored in the ASRS. If an order consists of full pal¬lets, then these are picked directly from that zone. Heavy goods (over 17kg) that are to be picked also go directly from the ASRS to a separate picking post, where they are placed onto the correct pallet with a hoisting system. The picking in that zone is supervised by WASS as well. Every action on the part of the operator has to be confirmed with the system.
Picking
SKF Logistics Services has a conventional picking warehouse with 40,000 locations for the other item picking processes. Wide and narrow aisles are combined here; allowing more than one picker to work in the wide aisles. Using the functionality "box calculation" the order collector can collect the items directly in or on the transport packaging that is most suitable according to WASS. This may be pallets, crates or boxes. Another important functionality of the picking concerns the maximum weight inspection. When the operator scans the label on the packaging unit after the picking, he can see if the total weight of the order corresponds with the weight as it should be. Some picking trucks even allow for a weight inspection per order line.
J. Leys: "An order may also specify an additional instruction. A maximum weight of 60 kg applies to pallets in some countries, for example. And so the operator must stay alert in that respect. We have meanwhile compiled a list of 180 specific instruction codes." An order picker can process a maximum of around 18 orders per pick run on his pick truck, depending on the size of the box. If a certain order proves to be too big for the type as proposed by WASS, then the picker can request a "box-type change" and report a different type of box to the system. Of course, it is also possible to use more than one box for one order. It is important that WASS always has the picker in the conventional picking take the heaviest goods first. An ABC analysis is made monthly and goods are moved – if necessary – as this limits the picking distances to a minimum.
Types of orders and shipment
SKF Logistics Services works with various types of orders. Three to four days of processing time applies to stock orders. A term of 24 hours applies to regular orders. "Same day" orders leave the same day if the order arrives at least two hours before departure. A so-called "taxi trip" is very urgent and has absolute priority over other orders. WASS sees to it that the most urgent orders are automatically picked first. And so orders that must be on their way towards 18.00h have priority over orders that are not expecting on the lading quay until after 22.00h. Once the order has been completed, it can be made ready for shipment. The necessary documents to that end are printed from WASS. SKF uses a combined carrier label on the shipment for some transport companies, so that the carrier will not have to re-label the shipment in his hub.
J. Leys: "Concerning the dispatching of goods, we have the possibility of making a so-called ‘pre-release’, that is to say a calculation of the volume that makes up the order. We sometimes have destinations with no less than 50 tonnes of goods. And so it is convenient, once the picking has been completed, that we know exactly how many trucks we need. We can also cancel trucks, if necessary, based on the pre-release."
Continuous optimisation
The success of a WMS implementation mainly concerns continuous optimisation: J. Leys: "All of the data that we can dispose of thanks to the scanning is stored in our warehouse and is optimally used. Based on that data, we can determine the individual performance of people, for example, and we can examine what went wrong in the event of a complaint. In addition, all of the employees can put forward so-called ‘process improvement requests’. For example, if a good idea is put forward in the sphere of IT, then it is discussed together with Consafe Logistics. I regularly discuss with the process delivery team whether the extra functionality could be useful to it as well. We have a new release once or twice a year, in which we incorporate the newest developments."
Read interview about it here