Cleanroom presses from Wickert: Key technology for elastomer processing

This is what typical components look like that can be manufactured on Wickert cleanroom presses. The industries include pharmaceutical, medical technology, biotechnology, etc., and so on. Wickert also notes an increasing demand for such products—and consequently for its presses. (Image: Wickert)

The cleanroom presses from Wickert Maschinenbau in Landau are also completely enclosed. The so-called gray area cannot contaminate the cleanroom. However, these are just some features that allow the machines to process elastomers in sensitive environments. (Image: Wickert)

This is what a cleanroom-compatible hydraulic press from Wickert Maschinenbau looks like, for example. To prevent anything from going wrong in these sensitive areas, the housing is made of stainless steel. Its contours are also designed to be easy to clean. But that's not all ... (Image: Wickert)

Wickert Machinery reports a significant increase in demand for specialized hydraulic presses for elastomer processing in cleanrooms. These systems are primarily used for manufacturing closure systems for pharmaceutical packaging, in the production of bipolar plates for fuel cells, or in sealing and machine components for semiconductor manufacturing.

The background is the growing interest in high-quality packaging components for expensive and sensitive medical active ingredients. More cleanrooms are also needed to meet the increasing demand for personalized medicine, such as pre-filled single-use syringes for self-medication. The COVID-19 pandemic already highlighted the importance of technology in vacuum compression presses for manufacturing these products.

Cleanroom hydraulic presses are used, among other things, for producing pharmaceutical closure systems made of butyl rubber (IIR) and bromobutyl rubber (BIIR). They are also used for producing sealing films for bipolar plates made of elastomers and for manufacturing valve membranes from polytetrafluoroethylene (PTFE) for applications in the chemical and medical industries. Additionally, rubber-metal connections for semiconductor manufacturing are produced on these systems.

Customized Solutions

Hydraulic presses from the world market leader for cleanroom presses are primarily used in elastomer processing when especially high quality standards apply. They meet the highest requirements for accuracy, temperature homogeneity, and process safety in sensitive applications. They are also designed to enable precise processing of elastomers in cleanrooms up to class 6 according to ISO 14644-1.

Wickert designs and manufactures the systems mainly as custom machines or in very small quantities according to customer-specific requirements. Since they are modularly constructed, they can be configured in many ways.

They achieve processing temperatures up to 500°C, pressing forces up to 100,000 kN, and planarity of 0.025 mm/m. For vulcanization of sensitive compounds, vacuum chambers with up to 990 mbar of negative pressure are used. This prevents air inclusions even in complex shapes and also optimizes the material utilization of expensive compounds.

A key criterion is the uniform temperature control in the tool. Modern multi-zone controls and closed-loop systems ensure that temperature deviations of more than ± 1 K are avoided. Because at typical processing temperatures up to 230°C, exceeding tight tolerances can negatively affect vulcanization and lead to scrap. Absolute control of these key performance indicators (KPIs) is therefore a guarantee of consistent, process-safe quality.

Encapsulated Systems

The fully encapsulated presses seamlessly integrate with your stainless steel cladding into cleanroom concepts. The use of auxiliary and lubricating agents is minimized. When they are indispensable, only non-toxic and physiologically safe materials are used. Moving parts of the machines are designed to prevent the escape of lubricants or auxiliary substances. This is achieved with high-quality sealing and wiper systems.

The maintenance area, called the gray area, and the production area in the cleanroom are strictly separated to prevent contamination. Hydraulic pumps, control cabinets, and control systems are located at the back of the presses, while the cleanroom where the compounds are processed is reserved solely for manufacturing. The design of the press interior meets all requirements for easy cleaning: it avoids undercuts and dead corners where potential contaminants could accumulate.

Automation Reduces Particle Load

About half of all new systems delivered by Wickert are partially or fully automated. Magnet clamping plates enable quick exchange of ferromagnetic tools within a few minutes. Systems for automated application of release agents ensure reproducible and consistent processes. This process takes place within a closed stroke field, and an integrated aerosol extraction system reliably prevents spray mist from contaminating the production area.

Mirrored human-machine interfaces (HMI) on the gray area and cleanroom sides further reduce particle entry. This allows setup personnel to perform all necessary tasks for mold changes from the gray area.

Monitoring According to GMP Standards

Modern systems utilize KPIs and quality switches to detect faulty process parameters early. All relevant data are securely documented in accordance with Good Manufacturing Practice (GMP). An access level matrix ensures that only authorized personnel can make changes to machine or recipe data. The "Audit Trail" function also allows operator actions to be monitored and logged.

Multi-Stack Presses in Tight Spaces

Fixed piping replaces traditional hose connections and eliminates the need for replacements every six years. This reduces operating costs and increases machine availability. Since space in the cleanroom is limited, space-optimized double-station presses also offer a way to double production capacity on the same footprint.

More Automation in the Future

Wickert anticipates significant advances in AI-supported process monitoring and energy efficiency in the coming years. The company also expects that skilled labor shortages and increasing variety of component types will boost demand for automation. Thanks to smarter setup concepts, automation will become increasingly economical even for smaller batch sizes.

Through continuous development and various retrofit options for existing systems, Wickert expects hydraulic presses for elastomer processing in cleanroom conditions to continue playing a key role in the future.