Beyond Omniseal® Blog

Selecting the Right Seal in Life Sciences: OmniSeal® Spring-Energized and Rulon® Polymer Solutions

Jul 17, 2018 / by Ronelle Decker

Choosing the right seal is critical in medical devices, surgical, pharmaceutical, and laboratory diagnostics applications to ensure patient well-being and handle performance requirements and tight tolerance specifications.  Let’s continue on to see what goes into selecting a successful sealing solution. 

What type of special requirements are needed? 

There are many factors that determine what type of seal design and material is needed, one of which is meeting chemical compatibility.  In HPLC (High-performance Liquid Chromatography) and UHPLC (Ultra High-performance Liquid Chromatography) equipment, they separate, identify, and quantify components in mixtures for pharmaceutical product development; therefore, the seal’s function is critical in order to avoid contamination and degradation and be resistance to a wide range of media. 

What type of sealing options are available?

Elastomer o-ring seals that rely on elasticity of the materials for sealing are often used in static applications in life sciences with moderate pressure and temperature demands. However, in many applications, due to compression set (loss of elasticity), elastomer o-ring seals may not provide a tight enough seal or tensile strength and are also confronted with aggressive chemicals.  In these stringent environments, spring-energized seals are a good alternative. 

Spring-energized seals consist of a PTFE-based compound, PEEK, or other polymer jacket encapsulating a metallic spring energizer.  Our OmniSeal® spring-energized seals maintain resilience and sealing force in aggressive media at extremely high and low temperatures, speeds, and pressures. Speaking of force, our seal was originally used in one of the most challenging sealing environments: cryogenic liquid propellants in rocket engines starting in the 1950s. In addition to providing a precise fit, the seal also offers high levels of purity to meet stringent cleanroom and other requirements. 

Other advantages of OmniSeal® spring-energized seals include: 

  • Chemical compatibility with and reliable sealing to prevent gases, human bodily fluids and liquids from damaging mechanics in pumps, valves, compressors, and surgical tools
  • The ability to withstand extreme temperatures [from -450°F (-268°C) to 600°F (316°C)]
  • Friction control for high speeds, resulting in low wear and long life
  • Ability to dry run with no lubrication 

Additionally, our team works with OEMs to create custom-designed sealing solutions to ensure minimal leakage, delivery of medication, clean oxygen, and other requirements for their specific applications. 

What are the different uses for Spring-energized Seals and Polymer Materials?

The following are a few applications that magnifies how spring-energized seals and polymer materials make THE difference in life sciences. 

UHPLC/HPLC: UHPLC and HPLC parts are regularly exposed to chemicals in separating, identifying and quantifying components.  Compatible material selection then becomes extremely important.  Polymer sealing materials such as our OmniSeal® Fluoroloy® A09 are used by major UHPLC and HPLC pump OEMs because they offer pressure ratings of up to 18,000 psi (1,240 bar) within a wide array of harsh chemicals. Aside from spring-energized solutions, we have other compatible materials options such as our proprietary Fluoroloy® seals and Rulon® polymer bearings maximize equipment run time while minimizing maintenance. 

In-vitro diagnostic equipment: IVDs used to test blood, tissue or other samples in order to detect medical conditions, monitor health, or capitalize on precision medicine are growing in use. With IVD systems running faster and longer today, they require low friction materials that are chemically inert and heat resistant. 

With over 20 FDA compliant or USP Class VI materials, we provide sealing solutions for IVD equipment in clinical chemistry and immunochemistry.  One of our applications includes syringe seals with the life requirement up to, or greater than, 250,000 cycles.  

Miniature motors: As laboratories reduce size to boost efficiency and OEMs look to design smaller, more versatile medical devices, miniature motors are increasingly being used in pumps and ventilation equipment and minimally invasive power tools. Our OmniSeal® seals designed with FDA and USP Class VI compliant materials address regulatory requirements while offering temperature cycling resistance, low friction, and low maintenance in a small footprint. 

Portable oxygen concentrators: With these and other wearable and portable healthcare options, a smaller footprint, low friction and low wear materials are necessary. Seals also need to run dry and be chemically inert. Rulon® material has been successfully used in piston cup seals for years in compressors in both stationary and portable oxygen concentrators. 

OmniSeal® seals are used in numerous other devices, including one of the first full-powered, battery-operated endoscopic staplers, where they withstand multiple steam autoclave cycles while sealing under low torque operating conditions. 

Which seal is best for your application?

Arriving at the best seal option and materials in life sciences is often a test in itself and dependent on how challenging the application and the operating environment are. Initial questions might include:

  • Are parts exposed to extreme alkaline or acidic chemical environments or aggressive media?
  • Should parts withstand extremely high or low temperatures?
  • Are micro seals needed to reduce footprint in design?
  • Is purity essential?  Do the parts need to be compliant with FDA or other requirements?
  • Must parts run with a low level of servicing?
  • Is it necessary for parts to be able to offer consistent and reliable performance? 
What expertise do you need for life sciences seal applications?

You should always search for experts in material formulation and sealing technology.  Because our parent company, Saint-Gobain, has hundreds of years in successful material performance and we have over 50 in sealing technology and 30 in life sciences, we have become a trusted partner, designing custom seals with medical, pharmaceutical, and surgical OEMs using FDA-approved and proprietary materials to meet unique specifications. 

Our extensive R&D and Design Engineering teams provide complete simulation and calculations related to wear and leakage based on material, seal, and spring design to ensure lifetime confidence. Testing focuses on:

  • Materials and processing - extensive characterization and validation
  • Applications - to support high speed, high pressure, high temperature, cryogenic conditions and lifetime testing
  • Simulation - with finite element analysis to model, design, validate complex designs to ensure they overcome issues with wear, design, shaft misalignment 

Are OmniSeal® spring-energized seals or Rulon® polymer materials a fit for your application?  Contact us today to find out!

Topics: Life Science

Ronelle Decker

Written by Ronelle Decker