Autor: Michael Diestel, Project manager PSI Metals GmbH
Plates are always transported to Salzgitter by rail, and to customers as well in some cases. The freight cars required for this purpose are supplied by Deutsche Bahn AG. To minimise transport costs, PSImetals takes into account the cars available during load planning. Its aim is to effect all shipments by the required deadline using the smallest number of freight cars. This has brought about a major reduction in demurrage charges.
Thanks to PSImetals, load planning, which used to be carried out manually, is nowadays more or less automatic using PSImetals. The plates to be shipped (shared/similar delivery dates, consignees, terms of shipment etc .) are grouped into load units by the load planning function and assigned to the relevant modes of transport (freight cars, trucks). Plates are stacked onto the transport system taking into account any restrictions such as maximum load capacity, grouping of wide loads and pyramid formation (plates stacked from large to small). Crane transport is optimised by shortening paths as far as possible and minimising crane usage. All results from the optimisation process can also be adjusted manually if required. The use of PSImetals has facilitated a major reduction in loading times as well as cutting down on crane transport.
Typical processes at Ilsenburger Grobblech GmbH involve putting plates into storage after production so they can cool down or for further processing at subsequent stations. However, they also include transporting them to supply the processing stations and any stock transfer necessary when switching between plant programs or loading plates for dispatch. PSImetals will work out the shortest possible route for all stock movements, allowing order processing times to be shortened.
PSImetals generates the plant programs needed for refining plates in Salzgitter. They specify the exact sequence in which the plates have to pass through the stations of the heat treatment line (furnaces/ quenching and tempering station). Here the software analyses the material according to the annealing specifications and the plate location in front of the line. The sequences determined are translated into automatic stacking instructions for the crane operators. The software also takes account of any restrictions in force for the plant stations, transport systems and routes as well as the applicable health and safety criteria (e. g. permitted stack height). The objective of plant-optimised stacking is to minimise restacking operations from the outset. One way of achieving this is to ensure that the plate sequence required in Salzgitter is already known when loading the freight cars in Ilsenburg. This has provided for a major reduction in order processing times for refined plates.
In addition, furnace bed planning has been carried out for the Ilsenburg plant, thus ensuring optimum distribution of the plates in the furnace beds. Furnace lots are formed automatically depending on the type of furnace treatment, plate data and its location in front of the station. This optimises utilisation of the furnace beds while minimising the number of restacking operations.
With PSImetals the inventory count takes place at the warehouse using mobile radio terminals which ensure it is completely up to date. It can be carried out for the entire warehouse or just areas of it (stock locations, rows or individual stacks). At the same time, the software automatically checks whether plates have been assigned to the right stock location sub-area. All data from the inventory count can be output as lists.
The permanent inventory count function in PSImetals stores the date whenever a plate is moved as well as the movement type. Where the absence of individual plates was once only noticed on dispatch, it is nowadays possible to check which plates have not been moved since a specific date or time — just by pressing a button. This means a search for such plates can be made as soon as possible and only takes a moment.
Where staff once had to walk around counting plates while production stopped for several shifts, the computerised inventory function in PSImetals can be performed without shutting down the plant. In addition, the data acquired is more accurate, and less time overall is required for the process.
Knowing exactly where a plate is located and when it will be finished and delivered is the basic requirement for improving the company's availability to deliver, order throughput and adherence to delivery dates. Although the legacy plate information system was provided for inventory management at the respective stock locations and stacks, it failed to include the position of each plate in the stack.
With PSImetals comprehensive material tracking is based on a full description of all systems (furnaces, quenching and tempering station, furnace unit, cut-tolength shears, leveler etc .), in addition to the transport routes/equipment used (overhead and gantry cranes as well as trucks, freight cars, platforms, trolleys etc .) and the available storage areas with their associated restrictions.
The precise location of a plate is determined using a Symeo Local Positioning Radar system, which acquires the relevant data from a total of 16 overhead cranes based in Ilsenburg and Salzgitter. Whenever the crane sets down a plate, PSImetals uses these coordinates to graphically display its location within the stack (essential for warehousing) as well as the position of the plate in the layer, e. g. with two plates in one layer or with materials of different dimensions in a stack.
To ensure plates do not get lost, PSImetals works with dynamic stock locations, which are automatically cleared after usage. Such locations make it possible to trace plates which during operations have been incorrectly left in areas without a stock location (e. g. on traffic routes). As PSImetals offers Ilsenburger Grobblech GmbH a complete overview of its stock of plates, there is no longer any need for manual searches.
Knowing where each plate is at any point at time is quite a challenge when producing 800,000 tonnes of plates per year. Ilsenburger Grobblech GmbH is part of Salzgitter AG and produces a major share of the Group's requirement for quarto plates. The company, whose main plant is located in Ilsenburg, also includes a production facility in Salzgitter. Around a third of the heavy plate rolled at Ilsenburg is refined in Salzgitter due to more stringent quality requirements. At both sites, the finished product is loaded onto trains or trucks for shipment to the customer. PSImetals, a system designed for warehouse management, material tracking and dispatch optimisation, supports production logistics at the plate finishing departments in Salzgitter and dispatch in Ilsenburg.
PSImetals WTM at Ilsenburger Grobblech GmbH