- Silicone Part Design Considerations for Medical Devices
- Begin with the end in mind
- Create a realistic timeline
- Determine funding for the project
- Communication is key
Silicone Part Design Considerations for Medical Devices
Designing silicone parts for medical devices is a complex and time-consuming process. A successful project can lead to medical devices that improve patient outcomes and help save lives. However, missteps in the design stewardship may result in regulatory delays, outright FDA rejection, inconsistent in-field performance, device failure, and potential patient harm. Below, we outline some key action items to ensure success for your medical device design project.
Begin with the end in mind
Early involvement with your chosen Design For Manufacturing (DFM) partners is critical for proper silicone material selection and part design commercialization. Get your medical device project started off right by ensuring you have considered the following:
Create a realistic timeline
There is an old adage: “Figure out what you want your medical device project timeline to be and then double it.” While this may be an exaggeration, it highlights the importance of allowing ample time for product design, iteration, testing, validation, and bringing your device to market. Rushing through important stages can lead to oversights and potential failures. A realistic timeline is essential to starting the project off on a path to success.
Determine funding for the project
Silicone projects are unique. The tooling is more expensive and complex than a traditional thermoplastic tool. For high-volume projects, a lead 2-cavity or 4-cavity development tool or bridge tool is often a responsible and justified expense before investing in a full-scale, multi-cavity production tool. Proper funding ensures that the project can proceed without financial constraints or the need to cut corners later in the project timeline.
Communication is key
Design engineers must work closely with process engineers, internal regulatory personnel, and other stakeholders to ensure that the device will function properly and meet its intended use criteria. Poor communication, both internal and external, can lead to misunderstandings, delays in the design process, and potentially, device failure.
Create a documentation mindset
Proper documentation is an essential aspect of the product design process. Every critical aspect of the developmental process, including material selection, design iterations, testing procedures, and validation results, should be kept in a central information storage location that can be accessed by all project team members. This ensures that a new project team member can step in and keep the project moving forward.
Hold an initial design review
A review of the application and functional requirements of the product is essential to informing component design. Design engineers must work early and closely with production engineers who are responsible for ensuring that the silicone part can be manufactured in a consistent and cost competitive process.
Select the right materials
Silicone is an incredibly versatile material. It is biocompatible, flexible, and has excellent thermal stability. Selecting the right silicone material grade with the properties critical to the device’s intended function is essential for ensuring performance. Engineers must consider where, how, and why the silicone component is required, the environment in which the device will be used, the technical knowledge needed to use the device, and the patient population. Designing a silicone component that is too rigid or flexible (a function of the silicone durometer) can lead to sub-optimal performance or device failure.
Design for manufacturability (DFM)
To keep that your project on the right path, make sure that the part design is capable of being produced repeatedly and consistently to the agreed-upon specifications. Three key methods of ensuring accuracy are computer modeling, 3D part printing, and prototyping.
Ensure quality robustness and regulatory compliance
Medical devices are highly regulated, and devices must comply with all appropriate regulations where they will be sold. Reviewing various US, European, and Asian agencies’ requirements is a must. Make sure your regulatory and quality groups are involved in the decision-making process throughout the project timeline.
Test and validate
Allowing enough time for design iteration, extensive lab and real-world testing, and validations are crucial. Essential tests include biocompatibility, functional, shipping, shelf-life, and durability testing.
Choose the right partners
It is critical to choose a supplier that has a significant history of bringing similar silicone projects to a successful conclusion. Globally, only a few top tool makers can build these complex tools. As silicone part size is reduced and complexity is increased, working with a company with all the necessary components to bring your project to a successful conclusion is a must. Ensure that they are fully staffed with competent personnel in engineering, regulatory, quality, manufacturing, and upper management.
Saint-Gobain has more than 45 years of experience and expertise in medical device manufacturing.
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