Driven by the competitive need for world-class performance, lean theory has now become a generally accepted improvement tool for the healthcare industry.
The gradual and consistent elimination of waste has already led to significant reduction of inventory and cycle times, improving cash flow, customer satisfaction and therefore bottom line profit.
For multi-product plants a continuous set-up is less favourable for reasons of very high set up times and consequent push to inventory. Individual processes may very well be continuous (for example milling, roller compacting or tablet pressing) and can appear to be very efficient in a multi-purpose pharmaceutical plant.
The continuous reduction of waste makes it possible to create true flow. Even if the movements between processes are not ignored (they are a waste to be reduced) the inventory decrease is still significant. A ‘Single Unit’ is to be based on the minimal average quantity as ordered by the customers. This translates directly to batch size. If batches are bigger than ordered you are producing to stock and increasing the inventory.
Continuous processing and continuous manufacturing
Economical batch sizes are also influenced by other criteria such as the cost of re-validation, limitations of existing equipment and time-consuming cleaning and QC activities. Kaizen events are a great tool to gradually reduce these influences. One major factor, however, is the manufacturing method and consequent scale-up limitations, already laid down in the R&D phase. This problem can be overcome by using continuous processes (for example dry granulation) rather the batch-based traditions. Such processes do not need to be scaled up and compliance to a lean batch size is simply a matter of run time. Certainly for single product facilities it is interesting to link the processes permanently together and achieve continuous manufacturing. But the additional cleaning and set up times, as well as synchronisation issues, make such a set up less beneficial for multi-product, flexible facilities using parallel processing techniques to maximise OEE.
Quality by design
Unjustly often linked to continuous manufacturing, QbD can also make a huge difference in making a batch-wise operation lean. Traditional quality control ‘by sampling’ lines up batches in quarantine thus creating large amounts of WIP-inventory. It also has a very negative impact on flow and cycle times and moves the organisation away from pull. QbD solves this problem as batches can be released ‘straightaway’.
A Matcon IBC blender is much faster than many of the other downstream process steps, so one machine could ‘serve’ many, provided the cycle time is not increased by traditional QC. Using PAT (in this case on-line NIR spectroscopy) this problem is solved and the OEE of the blender maximised.
The lean benefits of continuous process modules
Linking continuous (and batch) processes using a batch IBC system has significant benefits for reducing change over times (off-line cleaning) as well as relieving bottlenecks using ‘parallel processing’. Maintaining a steady state flow and full quality throughout the batch is very demanding on the bin system itself. The Matcon cone valve bin system guards this quality compared with other container systems by creating mass flow and control of feed. The Matcon system removes the risk of segregation, blockages and inconsistencies. Keeping a constant (and not flood-fed) head load on the inlet of the process, narrows variation at the output (for example a roller compactor). Avoiding segregation of often blended product is the most significant lean contribution of a Matcon system to reduction of defects.
In bin blending – a lean solution
Often overlooked or assumed a fact of life, the immediate danger of serious segregation when discharging a stationary blender is often a root cause of defects. Furthermore, when changing products, such blenders are very time-consuming to clean. This results in a low overall equipment effectiveness. A Matcon IBC blender eliminates these problems as the blend is not transferred to the IBC but remains intact. The Matcon blender itself is not in contact with product and requires no cleaning.