TriStar was contacted by a design firm that was looking for help on sealing an autoinjector pen used to deliver a new, highly viscous serum for the treatment of neurological disorders. They hoped that our EMD (Enhanced Materials Division) team could help them modify an existing material to improve its sealing properties in this demanding and precise application. Our ultimate solution was something else entirely. Read on for more.
Their Team Had an Appropriate Material and a Promising Approach – But It Just Wasn’t Quite Right
The customer wanted us to try vacuum deposition of fluoropolymer coatings onto Viton rubber O-rings. (Viton is a fluoropolymer elastomer and synthetic rubber compound commonly used for demanding sealing applications.) While that is certainly something our EMD scientists can do, it was obvious that ─ based on the very stringent time controls for the serum delivery ─ the use of an O-ring was not feasible in this case. Reason being, there were too many potential variations of cross-section and diameter tolerances, and consistent serum delivery could not be guaranteed.
Our Solution – A Precisely Engineered and Manufactured PTFE Spring Energized Seal
Our engineers considered the options for this very small part with stringent requirements, key among them that many thousands of parts needed to be made that would perfectly work every time. Our ultimate solution was to design a special spring-energized, FDA-approved PTFE seal, the tolerances of which could be tightly controlled in production.
After several design iterations we were able to meet the number one demand of the application, which was to deliver an autoinjector load of heavy serum to the patient within 7-9 seconds – consistently and completely. This level of reliability was crucial so that patients would be able to self-administer this product as prescribed, by counting out the duration using audio cues generated by the device itself.
Across Industries TriStar Can Help You Engineer Unique Solutions for your Challenging Applications
The TriStar engineering team was very pleased that we were able to come up with a solution to a unique sealing application and to contribute to this new technology for patient care. Over many years we’ve put our knowledge and experience to use to develop solutions for numerous customers working in many industries. If you have a challenging application for which a creative and unique approach is required, we encourage you to reach out to our team.
Consultative Engineering For Optimal Material Selection
