At first glance, Hallau in the canton of Schaffhausen is a cozy wine village where the clocks seem to go a little slower. However, as is so often the case, these small towns are home to medium-sized companies that produce innovations at the highest level worldwide. Hallauer Stamm AG is without doubt one of these creative, future-oriented companies. The plastics processors have dedicated themselves to the world of miniature and micro parts. And with great success. With the production of tiny components such as gear wheels, plugs or syringes, Hallauer pushes the boundaries of what is feasible. In the particularly sensitive field of medical technology, production takes place under controlled clean room conditions.
Micrometer-precise work
The smaller the products, the more complex and careful the manufacturing process must be. Every speck of dust can lead to functional impairment or even failure. If the products are also used in the medical technology sector, such as in minimally invasive surgery, absolute hygiene and contamination-free delivery must be guaranteed. Maintaining constant environmental conditions during production and packaging plays a major role here. Stamm AG has been micro-injection molding medical technology components under controlled clean room conditions for many years. The Swiss company has invested in new micro-injection molding machines and has now expanded its cleanroom capacity with a further CleanroomISO 7 cleanroom class. Detlef Moll, Managing Director of Stamm, explains the necessity of the investment: “We manufacture very small plastic components. This requires the highest precision. Our technicians develop injection molds that are in the m range for micro injection molding. The details of the end products are often no longer visible to the naked eye and yet they are important components in our customers’ overall concept. Every particle that contaminates production can lead to the failure of sensitive components. In addition to the precision of the process, we therefore also ensure a controlled production environment.” Stamm AG gained its first experience in cleanroom technology with a few square meters of cleanroom tent, which was used to inspect the parts produced. Convinced by the increase in quality, the Hallau-based company soon invested in a complete cleanroom system to which the injection molding machines were docked. With this solution, the machines were still set up outside the clean room as usual and fitted with a laminar flow enclosure, which enables controlled air purity within the clamping unit. The injection-molded micro parts are then removed by robots and fed fully automatically via encapsulated cleanroom conveyor belts into the Cleanroom, where the final inspection and packaging takes place.
Innovative injection molding connection concept
With their expertise in highly sensitive production, the order volume of the Swiss plastics experts grew once again and a further investment in two new micro injection molding machines with clean room production became necessary. In collaboration with their long-standing cleanroom supplier Schilling Engineering, the Swiss company opted for a new concept. In the newly commissioned 60 m2 cleanroom facility, which achieves ISO class 7 air purity, half of the machines are set up inside and half outside the cleanroom. A special outlet was constructed in the cleanroom wall for this purpose. This variant has several advantages, as Moll explains: “The new compact solution saves space and transportation routes. The injected products can be removed directly from the machine at Cleanroom. However, the injection unit itself is still outside the clean room, so that the heat loads do not occur in the controlled area. This has a positive effect on temperature control and air conditioning. This concept is completely new and was developed with us by our long-standing partner Schilling Engineering.”
State-of-the-art, energy-efficient cleanroom system
The newly installed CleanCell4.0 cleanroom system guarantees cleanroom air quality of cleanroom class ISO 7. Separate personnel and material airlocks with interlocking doors ensure the safe entry and exit of personnel and the packaged end product. The cleanroom system is equipped with high-performance ULPA class U15 filters . An innovative recirculation and return air system within the fully glazed cleanroom walls ensures precise cleanroom purging and has a high energy efficiency, as the already filtered and cooled air is fed back into the air exchange cycle. The wall and ceiling modules of the modular cleanroom are connected with a silicone-free GMP DichtClip system. The integrated CR-Control® control system provides additional safety. The control system’s interactive monitor is used to establish connections to the connected sensors that measure pressure, humidity and temperature, to filter modules, climate chambers, door and light functions and other components. All important functions are monitored and can be individually controlled and regulated. This also enables simple remote maintenance.
This article was published: KunststoffXtra 8/2018
