Wednesday, 16. December 2009

Material flow simulation for pharmaceutical production

A look into the future, often as early as the planning and construction stage, would be very helpful for the operational management of a plant. But statistical computations or experience become less reliable the more complex the industrial processes are.

This was the challenge confronting Schering GmbH und Co. Produktions KG (SPG) in Weimar. The objective was to react appropriately to the expected increase in demand even before a planned expansion of capacity so as to prevent gaps in supply. In addition, a projected change in the production split between tablets, film tablets and sugar-coated tablets also needed to be considered. Bayer Technology Services GmbH (BTS) performed a dynamic material flow simulation on behalf of SPG to master this challenge.

“The material flow simulation played a substantial role in our being properly prepared in advance for the changing market requirements of the future and thus being able to react accordingly,” explains Wolfgang Hoffmann, head of Production Planning at SPG in Weimar.

As part of such a simulation, existing production facilities and/or those currently in planning or under construction are digitally modeled and a number of scenarios are considered to derive optimization measures. At SPG, the BTS experts first surveyed the current production structure and modeled it with the existing production and logistics resources. The model depicted not only individual machines, containers and conveying equipment, but also the shift model in place and the production strategy.

In the next step, the model was validated using historical production data and initial scenarios were looked at to identify future critical resources. This revealed bottlenecks and also enabled immediate solutions to be developed for selected problem areas. The yield of the overall plant can be increased by procuring containers for use as transport containers and production buffers, for example.

 

The simulation showed that some machines would be overloaded by the planned production expansion. By evenly distributing the production orders among the available machines, downtimes and maintenance periods of individual machines can be used to relieve other overloaded (bottlenecking) machines.

BTS and SPG experts for production planning and manufacturing joined forces at a simulation workshop to develop new product-machine assignments so that production jobs could be better distributed among the machines in the future. This first meant identifying meaningful assignments and then reviewing them for technical feasibility, in particular with respect to the validation of the pharmaceutical production process. “Each simulation run brought us one step closer to a viable solution,” says Andre Afify, a simulation expert at BTS-PMT-Supply Chain & Logistics.

The results of the simulation workshop were compiled as a list of recommendations for which product should be scheduled at what time on which machine. This list is also an orientation aid for Production, as this is where the optimized production processes for all products must be designed, validated, and implemented in the form of new product versions in a timely manner.

(Schering GmbH und Co. Produktions KG produces and packages oral contraceptives and other solid dosage forms containing hormones for Bayer Schering Pharma AG.)