Press Release - 2 February 2004
A Model of Change

Simulation Modelling, undertaken by Coventry-based Production Modelling http://www.simulation.co.uk, has played a key role in both the successful delivery, and the on-going management, of an expanded warehouse and distribution facility for Walkers Snacks Foods.

One organisation that is benefiting significantly from the use of simulation technology is Walkers Snack Foods Ltd. The company recently invested in a major expansion of its Leicester based factory and warehousing complex, which includes its Southern Region Distribution Centre (SRDC), and equipment and process simulation played a crucial dual role in this project. As well as proving the design concept, and providing detailed process analysis that led to direct project savings, a detailed simulation model was also developed that is now being used an operational management tool.

Walkers’ Leicester complex includes two factories with seven production lines, and prior to the latest development there was also a single warehouse, with storage for 9800 pallets, and the SRDC, which provides case storage, picking facilities and marshalling lanes. This warehouse and the SRDC are sited side-by-side, and directly linked through a monorail system, that basically runs on a circular track round the SRDC. The expansion project, which was designed and implemented by warehouse solutions specialist Swisslog together with Walkers’ project team, has seen the introduction of a new warehouse on the other side of the distribution centre. However, rather than just provide additional storage space for 13320 pallets, the project’s aim has been to fully integrate the new warehouse with the existing facilities through the monorail system, (essentially feeding goods from the opposite side) and so create a combined operation that can deliver a significant increase in peak throughput, from 200 to 320 pallets / hour.

As John Coates, project director for Walkers Snack Foods, explains, “We believed that the existing facilities, and in particular the monorail system, had latent distribution capacity that could be utilised through this expansion project. But, significant questions remained as to whether the monorail would simply become too easily grid-locked in practice, when being fed from both sides, and what changes would be needed in equipment and infrastructure to handle more goods.”

To help confirm the concept and answer specific questions, the joint project decision team comprising of Walkers, IMI and Swisslog staff, turned to simulation technology and Coventry-based Production Modelling, a specialist provider of simulation, planning and scheduling software and consultancy.
“This simulation project has had two distinct phases,” notes Tim Cooke, senior project consultant at Production Modelling. “Initially we used our ProModel simulation software to model specific aspects of the system, in particular the monorail system.”

This model was not only able to answer the key question, that the system could be used as anticipated without any major configuration changes, but also provided important data for the overall project that would have only been found by expensive trial and error. For a start, it had been anticipated that to meet the increase in demand, up to six more monorail trolleys could be needed. But, the simulation was able to prove that there were already enough trolleys on the existing system to deliver the required increase in throughput, which meant a direct project saving of up to £150 000. The simulation further confirmed that when the system was not being run at peak throughput, it would be possible to park the unused trolleys in a new parking area, thus avoiding having to constantly rotate empty trolleys together with full ones.

“The flow of products within this new combined facility is very complex, and the simulation also highlighted how significantly the spread of products through the two warehouses could affect throughput. From this we were able to help assess and determine the best storage and dispatch rules for delivering the required throughput,” says Cooke.

The second phase of the simulation project was the development of a far more detailed model of the whole combined operation, which could be run at SKU level. However, as well as confirming the design, and helping to determine optimal operational speeds and feeds for various equipment, this model was developed for far more long-term reasons.

“We intentionally decided to invest in a far more detailed model than was strictly necessary for the design confirmation, because we recognised the important role such a model could play as an everyday management tool, helping with the ongoing management and development of the operation and its staff,” reports Coates. He adds, “It will prove invaluable for training front line managers, and all the SRDC staff - getting them used to the system on the model and learning about key issues. It is also currently being used to assess existing operational practices, and this has already shown that there is potential in the system for further improvements.”

Coates concludes, “Overall, the decision to apply simulation technology, and the expertise of Production Modelling, has proved to be a key aspect in the successful delivery of this project.”

End.