How hygienic design in supporting technologies optimises operational success (Part 2)  

Stringent standards have always been the guardrails for those creating sealing solutions for the pharmaceutical industry, and for companies using them to support their operations.  

Sustainability must now also be factored into sealing strategies and underpin fully integrated sealing systems for those running pharmaceutical processes.  

Design – creating better pharmaceutical vessel seals 

Achieving the perfect hygienic mechanical seal design for the pharmaceutical process industry is not about ticking a single box. Instead, it means meeting a set of core principles. In that way, creating new sealing solutions – or supporting the ongoing evolution of existing models – is a matter of aligning with changing guidelines.  

In short, pharmaceutical seals must be cleanable to meet strict criteria and perform consistently to support the business, and the same applies to other processing technologies.  

Successfully sealing mixers and agitators in pharmaceutical applications requires addressing significant regulatory and practical challenges. These include maintaining sterile environments, preventing contamination and meeting stringent regulatory standards, such as those set by the FDA and USP Class VI.  

Common mechanical issues include managing significant shaft misalignment, operating under vacuum or high-pressure conditions and preventing product damage from abrasive media. For example, the design of the Type 5280 vessel and mixer seal is ideally suited to products with higher viscosity or solid content, making them well-suited to special equipment such as dryers or process filters. 

How the right mechanical seal supports product purity and reliability 

Creating the optimal hygienic sealing components means meeting design criteria that can compromise product quality.  

Firstly, smooth surfaces to minimise the dead spaces and crevices that harbour microbes. Secondly, it must be robust to withstand exposure to powerful cleaning media - aggressive chemicals that mitigate contamination threats. Finally, heat tolerance is key. The materials of construction must be compatible with the extreme temperatures typical of Clean-in-Place (CIP) and Sterilise-in-Place (SIP) regimes. 

This is demanding on both the design and the seal that delivers business goals, but not optional. Meeting hygienic design criteria enables repeatable CIP and SIP, as needed, to reduce contamination risk while minimising the need for disassembly that disrupts production. But the effort is worth it. A hygienic seal delivers consistent performance across multiple process changes, supports validated manufacturing processes and improves overall equipment effectiveness (OEE). 

Role of filtration CIP filter elements 

Looking beyond the seal, other components in the wider sealing solution must meet the same standards if the wider process is to function effectively.  

John Crane optimises solutions for production-scale batches, fast, reliable setup reconfiguration and extended mean time between maintenance intervals. 

Filter systems and elements use smooth surfaces, minimal crevices and hygienic connections to avoid microbial retention and product residue build-up. The requirement for efficient batch processing means the design must enable full fluid process drainage, eliminate dead zones and be compatible with automated CIP and SIP cycles. 

Creating designs compatible with validated, repeatable cleaning processes requires pharmaceutical-grade, high-temperature, corrosion-resistant materials, such as 316L stainless steel and validated polymers, with surface finishes (Ra to 0.8 μm) that support cleanability and eliminate absorption. 

For automated CIP, filter elements use smooth welded joints, open-angle edges and customised connectors that support effective removal of product residues, bioburden and cleaning agents, as well as resistance to chemical, thermal and mechanical stresses during CIP cycles.  

Underpinning the process is not just about installing the right seal or even the appropriate sealing support system. It requires a full sealing strategy.  

Seal system configuration and support strategies 

The seal support system has a key role in managing the seal environment – in short, controlling cooling and pressure to maximise mechanical seal life. The support system must also contend with the same CIP or SIP cycles that demand so much from the seal itself.  

Seal and support systems combine to prevent product contamination, and process owners often favour inert-gas barrier support systems over liquid support systems to prevent batch contamination. 

Integrate design and operational function for sustained performance 

In summary, hygienic seal design and operational performance are inseparable in pharmaceutical production. 

Because reliable CIP/SIP operation is a given in this industry, an appropriately designed – and regulatory-compliant – system must be part of a wider sealing strategy that considers the entire lifecycle to support both sustainability and uptime, without separating the two.  

For the pharmaceutical process owner, selecting the right hygienic vessel sealing solution should not be about compliance alone – it should also support broader business and sustainability goals.  

Learn more: